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HomeMy WebLinkAboutBattery Energy Storage Opportunities in Alaska 1997| Hosted By Metlakatla Power & Light oso ole 5374 The U.S. Department of Energy and Sandia National Laboratories GNB Technologies : General Electric Company Northwest Public Power Association ELECTRIC UTILITY BATTERY ENERGY STORAGE SEMINAR Opportunities in Alaska AGENDA Monday, 4 August 1997 4:00 - 7:30 p.m. 6:00 - 7:30 7:30 - 9:30 Seminar Registration Seminar Reception Dinner @ Shaa Hit Banquet Room Tuesday, 5 August 1997 7:00 - 8:00 a.m. 8:00 - 8:15 8:15 - 8:20 8:20 - 8:30 8:30 - 9:00 9:00 - 9:30 9:30 - 10:15 10:15 - 10:30 Continental Breakfast / Registration Opening Remarks & Introductions Welcome Address Seminar Overview Energy Storage Systems Program Overview MP&L BESS Project Introduction, Utility Issues & Battery System Acquisition Technical Overview of the BESS Project * MP&L Grid Network * Technical Challenges * System Design Approach Break 'SNL = Sandia National Laboratories °GNB = GNB Technologies Ketchikan Westmark Cape Fox Lodge Shaa Hit Banquet Room Guest Speaker: TBD Day # 1, Ketchikan Shaa Hit Banquet Room Abbas Akhil SNL’ Dutch Achenbach MP&L’ Abbas Akhil SNL Dr. Christine Platt U. S. Dept. of Energy George Hunt GNB° Nick Miller GE’ °MP&L = Metlakatla Power & Light ‘GE = General Electric ELECTRIC UTILITY BATTERY ENERGY STORAGE SEMINAR Opportunities in Alaska AGENDA Tuesday, 5 August 1997 (Cont’d.) 10:30 - 11:15 11:15 - 11:45 11:45 - 12:45 p.m. 12:45 - 1:00 1:00 - 1:30 1:30 - 2:30 2:30 - 2:45 2:45 - 3:30 3:30 - 4:15 4:15 - 4:30 4:30 - 4:45 5:30 -10:00 MP&L System [T4] * System Integration * Battery, PCS, Controls * Charging / Discharging Open Discussion Lunch Northwest Public Power Association MP&L Economic Issues [T5] * Cost/Benefit * Design Issues BESS for Utility Storage [T6] Applications Break BESS Case Study #1 {T7] BESS Case Study # 2 Energy Storage Association Wrap-up Day #1 Review Day # 2 Logistics Dinner Day #1, Ketchikan Nick Miller, GE and George Hunt, GNB Shaa Hit Banquet Room Robert Martin VP, North West Public Power Association George Hunt, GNB Abbas Akhil, SNL Nick Miller, GE Abbas Akhil, SNL George Hunt, GNB Nick Miller, GE Dr. Phil Symons Chairman, Board of Dir. Energy Storage Assoc. Abbas Akhil, SNL Depart Main Lobby Cape Fox Lodge for Salmon Falls Resort ELECTRIC UTILITY BATTERY ENERGY STORAGE SEMINAR Opportunities in Alaska AGENDA Wednesday, 6 August 1997 6:45 - 7:30 a.m. 7:30 - 8:00 8:00 - 8:30 8:30 - 9:00 9:00 - 9:45 9:00 - 9:30 9:45 - 10:15 9:30 - 10:15 10:15 -10:30 10:30 -12:00 p.m. 12:00 - 1:30 1:30 -2:30 2:30 - 3:00 3:00 - 3:15 3:15- 4:00 Continental Breakfast Depart for Air Terminal To Annette Island Organize Groups for Tours Group “A” to Purple Lake Hydro Unit Group “B” to Chester Lake Hydro Unit Group “A” to Chester Lake Hydro Unit Group “B” to Purple Lake Hydro Unit Groups “A” & “B” Centennial Diesel Plant Groups “A” & “B” Pioneer BESS Facility BESS Equipment Overview * Battery Technology * PCS & Controls * Harmonic Filters & Switch Yard Lunch MP&L BESS Overview * System Operation * Dispatch & Maintenance * Performance & Benefits Open Discussion Close of Seminar Depart Metlakatla / Arrive Ketchikan [T8] [T9] Day # 2, Metlakatla Lounge Area, Main Lobby Cape Fox lodge Taquan Air Metlakatla, AK Tribal Long House MP&L Staff MP&L Staff MP&L Staff Dutch Achenbach & MP&L Staff John Kleba, GNB Nick Miller, GE Tribal Long House Jody Lenihan, P.E. Atlas Engineering Baton Rouge, LA Feedback MP&L, DOE, GNB, GE Taquan Air ELECTRIC UTILITY BATTERY ENERGY STORAGE OPPORTUNITIES IN ALASKA INTRODUCTION Welcome to the seminar on Battery Energy Storage System (BESS) technology. During the next two days, you will be hearing from several speakers talking about this technology and its use by utilities and industrial customers around the world to help resolve specific power delivery and power quality problems. Using the Metlakatla Power & Light BESS Project as an example, we will explore the basics of BESS technology, look at other typical BESS applications and consider opportunities in Alaska. The presentations scheduled throughout this seminar will present how BESS could be used as a strategic power management tool to reduce operating costs and improve the quality and reliability of delivering electric energy to customers. In 1997, Metlakatla Power & Light (MP&L) commissioned a utility grid connected battery storage system in Metlakatla, Alaska, which was designed and installed by GNB and General Electric. On day 1 of this Seminar, we will be discussing the utility specific conditions that lead MP&L to contract with GNB and General Electric to design and construct the BESS. We will review the system design and installation as well as its operation and benefits. On day 2, we will conduct a site tour of the MP&L power plants and the Pioneer BESS facility on Annette Island to give you a hands-on perspective of the facility. The agenda and material for the seminar is both educational and instructive, and will provide time for individual and group discussions during the next two days. We want you to relax and enjoy yourself. Most of all, we trust you will learn and take back with you a positive impression about battery energy storage as a resource that you could incorporate in your electric systems to improve power quality, reliability, and lower operating costs. Especially in the remote villages and towns of Alaska, we believe that BESS can have a significant impact on the environment by reducing the diesel fuel stored and consumed for electricity generation. This impact can be further enhanced by incorporating renewable energy sources that work well with a BESS. Special thanks to Metlakatla Power and Light for hosting the seminar, and to the U.S. Department of Energy for its support through the Energy Storage Systems Program at Sandia National Laboratories. We also wish to thank the Northwest Public Power Association for its co-sponsorship of this seminar and to the Energy Storage Association, Inc. for their participation. We also express our thanks to GNB Technologies and General Electric Company for their efforts in pursuing constant improvements in BESS technology and developing turnkey battery energy storage systems for utility and industrial customer applications. ELECTRIC UTILITY BATTERY ENERGY STORAGE SEMINAR OPPORTUNITIES IN ALASKA SEMINAR PROCEEDINGS Table of Contents U.S. Department of Energy + U.S. DOE Energy Storage Systems Program Introduction to MP&L BESS Project + Product ¢ Problems and Solution ° General Description Technical Overview of MP&L BESS + Utility Network + Load Profiles + System Design Approach MP&L System + System Integration ¢ PCS & Controls oa Charging/Discharging MP&L Economic Issues + Costs/Benefits + Design Issues BESS for Utility Applications Case Studies e Naknek Electric Association ¢ Vernon Recycling Plant BESS MP&L BESS Installation Hardware ° Tour/On-site Discussion - Pioneer BESS Facility BESS Performance and Operation + On-site Discussion Appendix + Miscellaneous Information Energy Storage Systems Program Sandia National Laboratories Battery Energy Storage Seminar “Opportunities in Alaska” Cape Fox Lodge Ketchikan, AK August 5 - 6, 1997 OES oc laetie un i Sandia National Laboratories «+ Opening Remarks « Introductions Energy Storage Systems Program Sandia National Laboratories Seminar Overview + Objective: > Showcase the Metlakatla Pioneer Battery Project > Review battery storage technology ~ Discuss applications in Alaska utility situations > Two day Seminar e One day of presentations e One day of hands-on discussions OLED Ouolao ican Sandia National Laboratories Seminar Overview (Cont’d.) + Hosts/Sponsors > Metlakatla Power & Light ~ U.S. Department of Energy and Sandia National Laboratories > Northwest Public Power Association « Invited Guest > Energy Storage Association, Inc. e Chairman of Board - Dr. Phil Symons Sandia National Laboratories Seminar Overview (Cont’d.) +» Seminar Agenda - Day 1 > Review of the ESS Program ~ Specifics of the MP&L Battery Project - Discussion of battery storage applications and brief case studies + Seminar Agenda - Day 2 > Visit MP&L generation units ~ Visit Pioneer BESS Facility Tab 1: Energy Storage Systems Progam Overview e Program Overview Presenter: Dr. Christine Platt U.S. Department of Energy Zs ESS U.S. Department of Energy Overview of the Energy Storage Systems Program Metlakata Dedication August 1997 Christine E. Platt, Ph.D., DOE/ESS Program Manager Program History Development of diverse components Emphasis on battery storage subsystems 1990s Integration and demonstration of turnkey systems NOW User focus in development of integrated storage systems O'm Energy Storage Program w Successes 1982 Gould cost-shared development contract resulted in Absolyte VRLA commercial products 1984 Comsat & JCI cost-shared contract reduced cost of nickel/hydrogen batteries by order of magnitude 1986 Exxon cost-shared contract resulted in zinc/bromide battery product licenses world-wide 1990 Silent Power cost-shared contract success led to construction of first high-temperature battery pilot production facility 1991 Utility Batter Group / Energy Storage Association formed with guidance and support from ESS 1993 1995 1996 1996 1997 Energy Storage Program Successes (continued) AC Battery & PG&E team with ESS on Power Management 250 kW integrated system PREPA supported through battery thermal management analysis for 20 MW plant AC Battery, PG&E, Wisconsin, and ESS cost-share development of 2MW Power Quality System -- now installed at Oglethorpe user site GNB cost-shared contract developed improved VRLA technology -- now installed at Vernon smelter Metlakatla Power & Light teamed with GNB / GE and ESS to install improved VRLA battery system Om, Deregulation Will Lead to ESS Traditiona J System Large, version alt —Generation el —Ragargmission i —Distribution Changes eee: Ad A New GEtity System {'{"{" Independent, interconiamiicd —Generation -Tilansmission \ a ation. Es tea. stripy \ Bak a Ni . = arket-driven S55. +Pfofit-based 7 Wholesale/ retail wheeling /. 4 O © Of: fi 4 & New Program Direction ESS Customer Service Applications Competitive Renewable Electricity Energy Industry Generation Fully responsive to the needs of the new electricity marketplace % @ Program Scope ESS Broad Technology Base @ Batteries ¢ Flywheels @ Ultracapacitors ¢ SMES Applications Focus on End Use @ Power Quality Telecommunications Peak Shaving Transportable Systems ¢-¢ ¢ ¢ Renewable Generation 4 @ Program Implementation | SSS) Integrated, modular, turnkey systems e Offer potential cost reduction as low as $500-750 / kW with volume production e Improved system performance and longer life e Seamless transfer e Components can be designed to optimize cost, volume, production, and performance e Standard components and products can be characterized, including reliability data e Directly address utility customer applications (power quality, telecommunications, transportability, peak shaving) Energy Storage Systems Program Key Industry Partners PARTNER Omnion Power Engineering & AC Battery Corporation ACTIVITY PM250 Development PQ2000 Development Hybrid Controller TBESS Development Pacific Gas & Electric and Arizona Public Service Prototype System Testing echnologies Improved VRLA Battery Development and Testing Metlakatla Power & Light System Testing ZBB Technologies Zinc/Bromine Battery Development Silent Power Inc. Sodium/Sulfur Battery Development ILZRO IEA Annex IX Frost & Sullivan Utility Market Assessment Arizona State University PV - Battery Market Assessment Energetics Technology & Utility Studies Sentech Renewables and Cost Studies University of Missouri - Rolla Systems Studies Energy Storage Association Outreach A ESS Program Elements Integration Components Transportable Systems Storage Component Development Renewable Systems Power Electronics Research Mid-Voltage Systems Component Evaluation Field Evaluations Analysis Benefits and Applications Studies Renewables Studies Technology Studies Jia ESS Projects Status - w Integration e Metlakatla, Vernon, and PREPA Battery Storage Projects Operating Successfully e TBESS 2MW for 15 sec Trailer-Mounted Power Quality System in Final Assembly by AC Battery Corporation e Advanced Battery Energy Storage System (ABESS) Development Project in Final Negotiation e Mid-Voltage (~12 KV) Substation Power Quality Development Project in Planning Stage With Utility Co-sponsor and Manufacturers e Renewable Generation and Storage (RGS) Integrated System Development Project in Planning Stage and Soliciting Input from Key Stakeholders 6m, Metlakatla Battery Energy Storage System ESS Om Metlakatla Battery w Energy Storage System os P| : - TP BE 0S Sawmill Load Swings Cause System Transients 6m Metlakatla Battery Energy Storage System 5 MW Diesel Generator Replaced By New BESS Om ESS Projects Status - w Components ¢ ZBB Zinc/Bromine 33 kW for 3 Hours Battery Pre- Prototype System in Final Factory Acceptance Testing ¢ VRLA Reliability Study to be Initiated « Power Conditioning Subsystem Industry Assessment in Progress « Testing of Batteries for Renewable and Stationary Applications On-Going at SNL « Cooperative Projects Planned With PNM, APS, ILZRO, NRECA, Oglethorpe, Crescent, and Several Labs (LANL, ORNL, NREL, ANL) ZBB Zinc/Bromine 33kW/3hr wy Preprototype Battery Sd ESS Projects Status - Analysis Study of SMES and Flywheel Energy Storage Technologies Identifying Key Characteristics and Research Needs Studies on Value of Storage to Renewables, Power Quality Applications for Storage, and ESA White Paper on Renewable/Storage Systems in Progress Leading US Participation Along With ILZRO in International Energy Agency Project on Electrical Energy Storage For Utility Applications Series of Utility and Industry Executive Meetings Complete - Report in Preparation Utility Systems Studies with UMR, SMUD and Chugach Complete - Reports in Preparation £@ Storage 2000 Promote the idea of a government/industry partnership to accelerate the introduction of storage under competition ¢ Augment network reliability, manufacturer productivity, renewable market penetration @ Market-ready, turnkey systems ¢ All distributed energy storage technologies ¢ Complement Renewable Generation & Storage Project 68 Program Technical Goals Integration 1997 Transportable Battery System Test 1999 Renewable Generation & Storage System 2000 Advanced Battery System Test 2001 Midvoltage PQ System Test Component R&D 1998 Flywheel Prototype Test 1999 VRLA Reliability Improvement 2000 Next Generation PCS Test 2001 Lithium Battery Development & Test 2003 SMES Subsystem Test Analysis [997 Value of Storage to Renewables Study 1999 Flywheel, SMES & PCS Technologies Studies 1998 Applications Benefits Study 1999 Customer Service Market Assessment 2000 Storage Technology Compatibility Study A Summary ESS Program has evolved @ Long history on industry-partnered R&D ESS Program is refocused on ¢ Attracting new customers due to restructuring of electric utility industry @ Developing new storage technologies for short and long duration applications « Advancing market-ready, integrated prototypes for a variety of customers A U.S. Points of Contact U.S. Department of Energy Dr. Christine Platt ESS Program Manager U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 (202) 586-8943 FAX: (202) 586-0784 E-mail: christine.platt@hq.doe.gov Energetics, Inc. Ms. Mindi Farber Senior Analyst Energetics, Inc. 501 School Street SW, Suite 500 Washington, DC 20024 (202) 479-2748 FAX: (202) 479-0229 E-Mail: mindi.farber@hq.doe.gov Sandia National Laboratories Mr. Paul Butler Manager, Energy Storage Systems Analysis and Development Department Sandia National Laboratories P.O. Box 5800, MS 0613 Albuquerque, NM 87185-0613 (505) 844-7874 FAX: (505) 844-6972 E-mail: pebutle@sandia.gov Energy Storage Association Mr. Jon Hurwitch Executive Director Energy Storage Association 4733 Bethesda Ave., Suite 608 Bethesda, MD 20814 (301) 951-3231 FAX: (301) 951-3235 E-mail: jwitch@switch.smart.net Tab 2: Introduction to MP&L BESS Project e Introduction e Utility Issues e Battery System Acquisition Presenter: George Hunt GNB Technologies Designing Battery Energy Storage Systems for Solving Customer Problems ¢ Typical Problem Areas for Utilities » generation » demand peaks » morning pick-up requirements » need for spinning reserve » minute-to-minute load regulation » second-to-second frequency control » delivery services » load growth ¢ Typical Problem Areas for Users » continuity of power » demand charge / time-of-day rate structure Designing Battery Energy Storage Systems for Solving Customer Problems Battery Energy Storage is a technology that can play a flexible, multi-functional role in a wide range of electric utility and user applications. Battery Energy Storage The Product enna « Battery Energy Storage System (BESS) is a technology requiring technical integration of components. » battery cells » power conversion equipment » station controls and monitoring systems » electrical substation, transformers, breakers » harmonic filters, coils, switchgear » foundation, building, auxiliary systems » utility interface, relays and controls » software ¢ ¢ ¢-¢ ¢ 4 MP&L BESS INSTALLATION Introduction to Project Metlakatla Indian Community, Annette Island Reserve Located in southeastern Alaska, 25 miles off shore from Ketchikan MP&L is a stand-alone electric utility grid consisting of: » 4.9 MW hydro generation (yearly rainfall 200 + inches) » 3.3 MW diesel motor generator Approximate fuel consumed per year: 475,000 gallons Centennial Diesel generator plant installed in 1987 MP&L services 800 customers Largest customer is Annette Hemlock Mill: 30% / 1.3 MW Metlakatla Power & Light Problems and Solution PROBLEMS @ Sawmill machinery loads create large voltage and kvar swings » up to 1 MW spikes for several seconds every 3 minutes » 1,000+ kvar reactive power needs » sawmill cycling demand runs over 18 hours, 7:00am to 1:00am Hydro units can not respond quick enough to handle voltage swings, provide system stability, or maintain frequency Diesel added to network for this reason, base loaded at 500 kW Average daily fuel consumption was 1,400 gallons @ $ .78/gal Diesel requires large fuel-oil storage tanks Diesel requires a scheduled 20,000 hour and 40,000 hour overhaul » cost $150,000 for minor and $250,000 for major engine overhaul « Operating expenses for diesel over 5 year period: $2.3 million ¢ ¢-¢ ¢ «64 Metlakatla Power & Light BESS Project Objectives OBJECTIVES Displace diesel generator in handling load-swings Reduce MP&L fuel consumption & operating costs Use “Renewable Energy” hydro power (water) verses fuel oil Provide better quality of power & service to customers Establish power delivery flexibility Reduce environmental impact of diesel plant operations Obtain black-start capability Address possible load growth and system stability issues oe ¢ © OU OHhUHD UM Sd ¢¢ ¢ «©¢ ¢ Metlakatla Power & Light Problems and Solution SOLUTION Displace diesel with a battery energy storage system BESS responds to load swings faster than diesel Pay back less than 3 years BESS capable of complete automatic unattended operation BESS will instantly source watts/vars when load jumps higher than the average system load requirement, and BESS will sink watts/vars when the load drops below the average system load requirement BESS steady state average output is zero (new AGC Controls) Battery is automatically maintained at about 80% state-of-charge so it can both source power / sink transients Diesel generator plant now used only for emergencies Metlakatla Power & Light BESS Project STATUS oe? © O—hUOHDhmUhSOH—hU%}}vhUhO}1 6 Hh OH O Project development started Sept. 1992 (Aavo Taaler) DOE project support through Sandia National Labs Six month GNB/GE feasibility study completed in 1994 Contract awarded Dec. 1995 (Dutch Achenbach) Site construction started in March / completed Dec. 1996 Commissioning test completed Jan. 1997 BESS became operational Feb. 1997 Diesel generator unit shut down Feb. 3, 1997 On-site technician assisted with MP&L start-up Three month performance period complete May 3, 1997 System performing “extremely well”, NO MAJOR PROBLEMS Dedication ceremony set for Thursday, August 7, 1997 Metlakatla Power & Light General Description of BESS Pioneer Plant System Ratings: » voltage at 1.0 pu 12.47 kV » peak power (10 sec.) 1.6MVA » continuous power 1.0 MW GNB/GE Technology » new dedicated building and switchyard (up gradable to 2 MW) » unmanned facility, about 2,500 sq. ft » BESS in series with utility grid » system sized for continuous 16 hour daily load leveling » Opportunistic charging between load swings » harmonic filter capacitor bank / inverter provides +/- 1,350 kvars » BESS design provides for black-start capability Metlakatla Power & Light General Description of BESS Battery ¢ ¢ ¢ Sg GNB ABSOLYTE IIP model 100A75, VRLA technology (AGM) One series string of 378 modules, 756 volts dc nominal Single module contains three 100A25 cells connected in parallel rated at 3,600 Ah @ 8 hour rate to 1.75 volts/cell Battery capacity: » 1 minute 7,158 A » 15 minute 3,354 A » 1 hour 1,872 A = 1.31 MWh » 1.5 hours 1,500 A* = 1.62 MWh » 2.0 hours 1,275 A = 1.83 MWh » * 1 MW (1,500 A) is limitation of continuous rating for PCS 900 kW swing load (up to 15 seconds) = 1,150 amperes Metlakatla Power & Light General Description of BESS Power Conditioning System _ (GE) One power converter pair (PCP) 12 - pulse bi-directional voltage source using GTO thyristors Self commutating full 4 quadrant operation Inverter (discharge) / rectifier (charging) Peak power (10 seconds) 1.6 MVA Continuous rating 1.0 MW One way efficiency 95% Inverter provides plus-or-minus kvar support Capacitor bank sized for 1,350 kvars (harmonic filter) » adjusted by MP&L operator as needed Harmonic distortion meets IEEE 519 ¢-¢¢—hlUhhUh OOrhUhS/ OH HF O a4 Metlakatla Power & Light Customer Benefits Multiple Battery Benefits Defined ¢ Battery system allows MP&L to operate without diesel generator » monthly savings are reported to be $39,100.00 ¢ Improved stability of grid network (damping or first swing) » voltage regulation and frequency control » improved power quality (kvar support) Reduction in air emissions (improved local air quality) Overall MP&L system reliability/flexibility greatly improved Significantly reduced fuel-oil storage requirements Non-hazardous materials used Battery fully recyclable Diesel now provides emergency backup power BESS has responded to three events requiring full power output ¢¢ ¢—Om6m—hUhO%hUO}D™lUM Tab 3: Technical Overview of the BESS Project e MP&L Network e Technical Challenges e System Design Approach Presenter: Nick Miller General Electric Power Systems Engineering Technical Overview of MP&L Battery Energy Storage System Project Nichoias W. Miller GE Power Systems Ye \oelel O Power Systems Engineering Simplified Metlakatla System One-Line PURPLE LAKE HYDRO CHESTER 1.441 MVA HYDRO 90% PF ce awa 4.16 KV 3 85% PF LION 12.47 KV 1.25 MVA 5MVA DIESEL 80% PF 4.16 KV 24KV 85% PF SAWMILL Power Systems Engineering Typical Metlakatla System Load Profile Frequency PU 1.01 .99 1.02 - Centenial Terminal Voltage pu 98 Centenial Generation kW 0 yy 0 4 Time (Hrs) Centenial Reactive Power k Var 2000 2000 Sawmill Power kW Sawmill Reactive Power k Var 1000 Time (Hrs) Power Systems Engineering Typical Metlakatla System Load Profile (Detail) Frequency PU Centenial Reactive Power kVar 1.01 1500 99 500 - 1.02 Centenial Terminal Voltage pu 1500 .98 2000 1 Centenial Generation kW 500 500 500 ~ a e epepaeepaq -500 a+ RRR eee 0 1 0 1 Time (Min) Time (Min) wd) Power Systems Engineering Technical Challenges for System Performance: e Maintain system Frequency e Maintain System Voltage e Share Active Power Load with Generation e Share Reactive Power Load with Generation and other VAR sources e Satisfy PCS (P,0,V,I) Requirements e Satisfy Energy Balance Requirements for Batteries e Function Property with or without Diesel On-line e Meet or Improve on Performance of System with Diesel Metlak 94.09.19 Power Systems Engineering Expected Performance of System with BESS Without Slow Reset BESS active power kW Time (Hours) 21-82D Power Systems Engineering Expected Performance of System with BESS with Slow Power Reset 1500 BESS active power kW 1000 - se A ele ei 0: 500 = -1000 50 Time (Hours) 21-92D / (36) Power Systems Engineering Simulated Comparison of System with BESS vs. Diesel Sawmill Vterm Sawmill Pelec kW 2000 + 1.04 J 1.01 | Avg. Sys. Fr 0 ~ Sawmill Qelec kW 1.01 B. Sys. rea. 4 800 + 500 | 99 BESS Active Power kW 2000 7 Dieee Pgen kW BESS Reactive Power k Var o- Diesel Qgen k Var ' 300 7 1000 4 iim «OO TT . THOTT TTY Pre yee ee TTT] 0 10 0 / 10 Time (Sec) Time (Sec) 21-92D @) Power Systems Engineering System Design Approach: e Use Standard, Commercially Proven Components e PCS and Controls are GE Industrial Drive Technology e Batteries are GNB Industrial Technology e Make BESS Control Simple and Understandable Metlak 94.09.19 @3) Power Systems Engineering Battery Energy Storage Systems (BESS) Simplified One-Line Diagram Load PCS BESS Transformer Battery Utility Bus tO} & Metlak 94.09.19 wd Power Systems Engineering BESS Active and Reactive Power Capability Phasor Diagram Equivalent Circuit VB VB - 7 x ’ io lee Network : Vr ; Uo hk i Je Reactive Power (kVAr) Capacitive Converter Capacity a Active Power (kW) Charging Discharging Inductive Metlak 94.09.19 Power Systems Engineering BESS Control ¢ Emulates rotating synchronous machine, but with some advantages: - Inertia, governor droop, and damping controlled to suit needs of system - Supplies and absorbs energy (within battery capacity) - Faster control of active and reactive power Metlak 94.09.19 Power Systems Engineering BESS Control ¢ When connected to power grid: - Terminal voltage maintained by control system - Frequency & phase of BESS voltage adjusted to supply required power ¢ During isolated operation, PCS establishes frequency and voltage. Metlak 94.09.19 BB Power Systems Engineering BESS Ratings: Power vs. Energy ¢ Power Conversion Module rating = max. kW output ¢ Battery rating = total energy in kW-hr For example, a 2000 kW-hr battery can deliver: - 2hours of power at 1000 kW output - 1 hour at 2000 kW output ¢ Increase total energy storage by adding more batteries in parallel without extensive system modifications. Metlak 94.09.19 Tab 4: MP&L System e System Integration e Battery, PCS and Controls e Battery Charging/Discharging Presenters: George Hunt, GNB Technologies Nick Miller, General Electric Power Systems Engineering MP&L System Design Nicholas W. Miller GE Power Systems Metlak 94.09.19 BESS System Schematic Battery System : = Battery Monitor [ Personal Computer Cd | ot Remote Operator's Panel Disconnect : Power Converters e GTO converters connected as Power Converter Pairs (PCP) via transformers. e Transformer connections and firing control make PCP look like 12-pulse converter. Power Converters e GTO-based bi-directional converters with PWM firing control. e 4-quadrant operation allows converters to supply or absorb real or reactive power in any combination, within converter limits. e Emulates rotating machine with very low inertia, for fast response to varying system needs. Power Converter Capability Reactive Power (kKVAr) Rated Capacitive Converter , <— Overload Capacity \ “7 Capacity Active Power (kW) Charging . . Discharging Inductive Equivalent Circuit VB Iy Xx OC) < Yt | Distribution ——- Network Phasor Diagram Power Converters 7 ot EY TE a8 && j H ne a 4 a i ' a ' 1 J 4 Capacitor {J Converter | Converter 21-82D Power Systems Engineering Simplified BESS Power Control Battery Energy Management System Dey Governor Droop 1.0 Pgem — Power order from battery energy Py, — Hydro turbine output power. sir alc ama P, — Load power demand. Pp — BESS output power. : ®Bo — BESS frequency order. Puo — Hydro turbine power order. Battery Monitor Control Implemented in PLC, interfaces to Operator Interface PC and Power Converter Control ¢ Calculates state-of-charge * Controls charging and discharging ¢ Monitors battery status and health e Records battery operation ¢ Detects ground faults Power Systems Engineering Simplified Battery Monitor Equipment Sketch To Governor Controls Cables Signal Isolation Boxes SO \ L — 7 21-92D >» +2.00 volts dc nominal potential cell (Nernst Equation) > Overall electrochemical reaction PRO Discharge REACTANTS ——> PbO, + Pb + 2H,SO, *Charge 2PbSO, + 2H, 0 Charged —>+ PbO, : lead dioxide (positive electrode) Charged ——-» Pb_ : sponge lead (negative electrode) 2H,SO, : sulfuric acid (electrolyte) Discharged ———-+ _: both positive & negative electrode converted to PbSO, (lead sulfate) and electrolyte converted to water H,O GWH:21694D LEAD-ACID STORAGE BATTERIES SIMPLIFIED TECHNOLOGY OVERVIEW Traditional Wet Flooded Lead-Acid Cell >» On charge, the lead sulfate (PbSO4) in the positive plate is converted back to lead dioxide (PbO2). Oxygen is generated on "overcharge" at the positive. > On charge, the lead sulfate (PbSO4) in the negative plate is converted back to sponge lead (Pb). Hydrogen is generated on "overcharge" at the negative. > H2S04 is the active component in the reactions at both electrodes. Overall Result: Water loss and cell gassing. Therefore, flooded cells require periodic water replacement. GWH:21694E SIMPLIFIED TECHNOLOGY OVERVIEW > The same basic electrochemical reaction occurs during discharge as compared to a flooded or wet cell; however, the "BIG" difference occurs during charge. > In arecombination or VRLA cell, during charge, the oxygen generated at the positive is combined chemically with the freshly formed lead at the negative in the presence of H,SO, to provide lead sulfate and water. > The oxygen at the positive suppresses generation of hydrogen at the negative. Overall Result: No water loss or venting of gas. Therefore, VRLA cells are maintenance-free. GWH:21694F LEAD-ACID STORAGE BATTERIES SIMPLIFIED TECHNOLOGY OVERVIEW CHARGING .... . - ose? 4 Out Gassing Flooded Electrolyte * Positive electrodes generate oxygen during overcharge. * Negative electrodes generate hydrogen during overcharge. * Gassing is two parts hydrogen and one part oxygen. GWH:21694G "SEALED" Immobilized Electrolyte AGM or Gell* * Oxygen given off at positive electrodes is recombined at the negative producing lead- sulfate and water. ¢ Separator or immobilization of electrolyte allows oxygen as a gas to transfer to the negative. *Assumes Gell has already developed cracking structure. LEAD-ACID STORAGE BATTERIES SIMPLIFIED TECHNOLOGY OVERVIEW Charge Acceptance / Gas Evaluation @ 25°C Specific_, Gravity Charge Accept. Ah 100 80 60 40 20 0 0 20 40 60 80 +——_ DISCHARGED % RECHARGED 100 120 CHARGED —————»> GWH:021694H — LEAD-ACID STORAGE BATTERIES SIMPLIFIED TECHNOLOGY OVERVIEW Charge Acceptance / Gas Evaluation @ 25°C Specific_, Gravity Charge Accept. 0 2 setPi SHH: eae THESES: gee 0 20 40 60 80 100 120 +#———— DISCHARGED % RECHARGED CHARGED —————> GWH:0216941 eee hand Mie ete hel Rely Met lakatla E ery Monitoring System BESS Alarm || & SOC% 96 KWOrder -3 Battery Mode _ 4 _ Load Leveling Hees | Black St: Strings 1 | Black Start a | aut Pei TABIT 12:07:47 PM Communications with PLC - OK oS cu | Trendi ng (Click on chert to select variables and time. Legend below gives scaling for common signals.) 100.00 80.00 60.00 | i 40.00 | 20.00 i 0.00 Jul-24-97 dul-24-97 Jul-24-97 dul-24-97 Jul-24-97 Jul-25-97 00:00:00 04:48:00 09:36:00 14:24:00 19:12:00 00:00:00 f 0= 100 = TowerVoltage OV 22.14V Hydrogen Sensor0% 100% Battery LeaW’Gnd 500V 500V 1 fi StringVoltage OV 1000V Pilot Cell Voltage OV 3.00V State of Charge 0% 100% Amp-Hours OAHr 10, 000AHr 1 String Current SO00A 5000A Temperatures OC 200C Bess KW/KVais 2500KVA 2500KVA = Power Order 2500KW 2500KW | j seed [ onetine | | saten | | ser | | tending | [maintenance| gf # t ae ha da - [MP&L BATTERY MONITOR] Metlakatla BESS / Battery Monitoring System BESS Alarm | | SOC% 95 KW Order 0 see ee _ Load Leveling bea | Black Start Strings pe Sea ieee Discharge Test TPRBIST 09:24:54 AM Communications wkh PLC. OK caueiee Ae eccaliee Trending (Click on chart to select variables andtime. Legend below ges scalingfor common signals.) 100.00 80.00 Sel 60.00 40.00 20.00 0.60 L_ Jul-24-97 dul-24-97 Jul-24-97 Jul-24-97 Jul-24-97 Jul-24-97 06:00:00 08:00:00 10:00:00 12:00:00 14:00:00 16:00:00 O= 100 = TowerVoltage OV 22.14V Hydrogen Sensor0% 100% Battery Leak/Gnd 500V 500V String Voltage OV 1000V Pilot Cell Voltage 0V 3.00V State of Charge 0% 100% Amp-Hours OAHr 10, 000AHr String Current SO00A 5000A Temperatures oc 200C Bess KW/kKVars 2500KVA 2500KVA Power Order 2500KW 2500KW Alarm Panel One Line | | Bate | SER | trending | |Maintenance| g 4 » Cee eee a al a ca le abet dahlia éry Monitoring System "Metlana.la BESS / BESS Alarm soc% 96 KW Order = -0 Battery Mode — | Load Leveling hae | Black Start Strings, 1 ee Discharge Test as | . {oe tage 7128197 12:10:14 PM Communications with PLE. OK Poiiae | | Alto” | Paunline i 1 Trending (Click on chert to select variables and time. Legend below gives scaling for common signals.) Print 100.00; 60.00 40.00 20.00 0.00 | Jul-24-97 dJul-24-97 Jul-24-97 Jul-24-97 Jul-24-97 Jul-24-97 11:30:00 12:06:00 12:42:00 13318500 13:54:00 14:30:00 { d= 100 = TowerVoltage OV 22.14¥ Hydrogen Sensor 0% 100% Battery Leak/Gnd SO00V 500V StringVoeltage OV 1000V Pilot Cell Voltage OV 3.00V State of Charge 0% 100% Atnp-Hours OAHr 10 900AHr String Current 5000A 5000A Temperatures OC 200C Bess KW/KVars 2500KVA 2500KVA = Power Order 2500kKW 2500KW Fsieenad [ oneuine | | eatey | [ser | | trending | [mainenanss 2 4 > aC mmm 01x Metlakatla BESS / Battery Monitoring System ‘ : Battery Mode — SOC% 96 KW Order § -13 _ Lead Leveling } Black Start Strings Sie eames Discharge Test — | ai ; me ize 7RBIST 12:11:10 PM Communications with PLC - ok Equalize = Auto Off paunlies : Trending (Click on chart to select variables and time. Legend below gives scaling for common signals.) “af 100.00 } eee aL Ee 60.00 pe ag at a a rT % Nak ng oo Ha rH nH a edad Lik) 7 40.00 20.00 ‘ 0.00 Jul-24-97 dul-24-97 Jul-24-97 Jul-24-97 Jul-24-97 Jul-24-97 11:30:00 11:42:00 11:54:00 12:06:00 12:18:00 12:30:00 ‘ d= 100 = TowerVoltage OV 22.14¥ Hydrogen Sensor0% 100% Battery Leak‘Gnd S00V 500V StringVoltage OV 1000V Pilot Cell Voltage 0V 3.00V State of Charge 0% 100% Amp-Hous OAHr 10900AHr String Current 5000A 5000A Temperatures Oc 200C Bess KW/KVars 2500KVA 2500KVA Power Order 2500KW 2500KW | [aiernrancl] [ onene | [ satey | [ cer | | trending | [wairtonance| g a4 aah RTT aba : — etlakatla BESS / Battery Monitoring System anor cececr! BESS Alarm $OC% 96 KWOrder -1 cee _ Load Leveling pe: Black Start | i Strings i : pS ot Discharge Fest i 7129197 12:17:45 PM Communteations with PLC - oK Equalize = Aulo Off ane ' PCI PCH PCO Poo Po Battery 211 ]¥ 2.10|¥ 2.40] [2i1]y 210] ¥ 210]¥ fice 21 |¢ Se 17.0] 170] 170] 170 17.0] 170] 170] 1701 170 [45 watts | [ait |y [211 ]¢ 212|¥ etal [21 |e [2 Jc [21 Je [2 Je [21 Je [Ze PO P Ambient @ (Q[ 22 | Hydrogen @ @LEL) [ 24 | String #4 Ambient #1 (9 Hydrogen #1 (&LEL) | 9 | c 170 | 106 | 17.0 String #1 Stack # aE ASIN SII HPN CF MN LEE SSIS ORION YE OE Alarm Panei| [ one Line | | Battery | | SER | | Trending | |Maintenanca| oO + 4 Mae (MP&L BATTERY MONITOR] letlakatla £ jp eeeee SOC% 96 KW Order = -0 _Bettery Mode _ Load Leveling Strings | 1. | Black Start ; Digcharge Fest Equalize | Auto Off | Equatize 7P99T 12:19:56 PM Corrimunications with PLC - OK | Maintenance Equalize Ss ea | "| Automatic Equalize Setup EtterValue Auto. Last equalize: i Leh i i er: Equalize peal : Desired hour of day to begin | O=mildnight, 23-110 “ 9 | 23 Days until next equalize: 96 | Desired day of week roy Manual at_]{ Stop | CAUTION: Stop will initiate an inimediate discharge (= Sunday, 7 Saturday) t Equalize OO SED Desired interval (days) 180 (Immediate) & Current. during discharge 375 Amps G0 minimum, 500 maximum) ; Discharge Test Desired string current ie We novan a Discharge test string current | 375 Amps Discharge test duration ‘25. 5 Hous Ground Fault - Extend Trip Delay by 8 Hours [itend) 9 Hour Extension Enabled Total String 1AHrs, In: -120634 Out: 120086 Alarm Panel [ one uine | | eatery | | SER | [ Trenaing | |Maintenance| og ¥ ei > EN EASE DO NETTIE REBT NC RETARD ACSI OTA RAN IR CNS TENTH LOATH RAR Tm LAN CEFR EOL, RCO HPN Tab 5: MP&L Economic Issues e Cost/Benefit e Design Issues Presenter: George Hunt GNB Technologies MP&L BESS Project Presented at BESS SEMINAR OPPORTUNITIES IN ALASKA August 5, 1997 Westmark Cape Fox Lodge Ketchikan, Alaska by George Hunt GNB Technologies Gallons/month Metlakatla Power & Light Monthly Fuel Consumption 50,000 40,000 30,000 20,000 10,000 1996 (w/o BESS) 1997 (with BESS) Metlakatla Power & Light Gross Monthly Generation, kWh 2,500,000 = 2,000,000 ~ — 1,500,000 kWh Metlakatla Power & Light Monthly Billed kWh 2,500,000 2,000,000 1,500,000 1,000,000 500,000 : 1996 Feb Mar Apr May Jun LEAD-ACID STORAGE BATTERIES BATTERY ENERGY STORAGE SYSTEM SYSTEM OFFERING FUSB DISCONNECT - HIGH VOLTAGE TIE (ABOVE 15KV) See S REMOTE CONTROL / DIAGNOSTICS INSTALLATION (Basic Scope Only) HARMONIC FILTERS FINANCING 6. SEISMIC ZONE 4 “TROMBONE PD SERVICES Project Manager . Site Manager DC DISCONNECT (Battery String) © Installation . Training Maintenance BATTERY A. Monitoring y i . Testing-Inspection SERVICES Technical Direction Project Coordination Data for Customer Regarding Permits and Public Utility Commission (PUC) Relay Study for bus tie in Harmonic Filter Study Installation - Engincering Battery Recycling GWH:21694T LEAD-ACID STORAGE BATTERIES BATTERY ENERGY STORAGE SYSTEM PERCENTAGE OF PRICE BREAKDOWN VRLA Batteries : | VRLA Batteries 32.250 PCS / Transformers F “| PCS/ Transformers on Balance of Plant i “31 Balance of Plant SUBTOTAL : : SUBTOTAL HELCO Interconnection ; | Transportation / Packaging | | Sales Tax AFODC (Cost of Money) ; eee 7 State | County Secondary County - SUBTOTAL i : SUBTOTAL Transportation / Packaging 4.418 | Sales Tax 4.167 | susroraL | sts | TOTAL 100.000 | GWH:21694W Tab 6: BESS for Utility Storage Applications e Utility Applications Review Presenters: Abbas Akhil, Sandia National Laboratories Nick Miller, General Electric AOC uae nD E Sandia National Laboratories Battery Energy Storage Systems ce) Utility Applications Abbas Akhil Sandia National Laboratories (505) 844-3353 aaakhil@sandia.gov Energy Storage Systems Program E Sandia National Laboratories Today's Perception of Battery Storage + Distributed, diversified applications: Generation, T&D, Customer side + Smaller plant size and investment: > <1-10 MW plant size - 2-3 hours of storage «+ Turnkey systems approach: ~ Single source supplier: warranty, financing ~ Modular, transportable CCR cae un Sandia National Laboratories Applications and Requirements Application Power (MW) Storage (hr) Spinning Reserve 10 - 100 0.5 Capacity Deferral 10 - 100 ya Area/Frequency Regulation 10 ra Renewable Applications 1 1-4 Load Leveling 100 pa Transmission Line Stability 100 Voltage Regulation 1 (MVAR) Transmission Facility Deferral 10 Distribution Facility Deferral 1 Demand Peak Reduction 1 BU lli@e) 7) ete aero le lea tiled) i Customer Power Quality Energy Storage Systems Program |» Sandia National Laboratories U.S. Utility Battery Storage Systems Company Name Application(s) Size (MW/MWh) Operational Date Crescent Electric Peak Shaving 0.5/0.5 1983 Coop. Southern Load Leveling/ 10/40 1986 California Edison Transmission Line Stability San Diego Gas & Transit Peak Shaving Loe 7[ oe. Electric Puerto Rico Frequency Reg. / 20/14.1 Electric Power Spinning Reserve Authority GNB - Vernon Reliability/Peak Shaving §/3.5 Srila Oglethorpe Power Power Quality 2 MW/10 seconds Metlakatla Power Voltage Support 1.2/1.2 & Light aC Oncaea 7 Sandia National Laboratories Suppliers and Capabilities + GE/GNB: turnkey lead-acid systems: 2 - 10MW «+ AC Battery: modular, transportable lead-acid systems: 30kW - 2MW + Superconductivity Inc.: SMES and battery systems: 6 - 12MJ + Exide, C&D, JCI, East Penn: Batteries + ABB, Westinghouse, SPCO: Power conversion, controls eee Energy Storage Systems Program 7 Sandia National Laboratories / I Fo = | Power Systems Engineering BESS Applications Alternative to UPS for Standby Power Backup generation Voltage Support Energy Management - Industrial Peak Shaving - Utility Demand Side Management Power Control wd) Power Systems Engineering Comparison of BESS and UPS AC System Hi! BESS Simple BESS Connection Simple UPS Connection Fy “Protected” load “Protected” load Metlak 94.09.19 Power Systems Engineering Comparison of BESS and UPS BESS UPS connection shunt connected series connected isolation requires switching to isolate bus dc bus buffers disturbances (speed dictated by application) losses negligible when not charging or losses due to load current passing discharging through converters (if no bypass switch) power converters one: ac«>dc two: ac->dc and dc-ac voltage regulation | continuous not normally possible power flow bi-directional flow possible for both real and reactive power unidirectional Metlak 94.09.19 Power Systems Engineering 1) Isolation: 2) Control: 3) Capacity: Criteria for BESS as UPS Quickly isolate served load from main system bus during disturbance (particularly. voltage depression or momentary outage). “Isolated” system must regulate both frequency and voltage: - energy storage - governor function - continuous control of reactive power - voltage regulator Provide necessary active & reactive power and energy for regulating functions. Metlak 94.09.19 wd) Power Systems Engineering BESS as Alternative to Backup Generation ¢ Power Quality and energy cost considerations: - poor power system reliability - obtain less expensive interruptible service rate ¢ BESS advantages: - avoid combustion & fuel storage permits - no fuel storage - no emissions - essentially no moving parts - low maintenance Metlak 94.09.19 Power Systems Engineering Voltage Support Balance of Plant Load Continuous Voltage Regulation By BESS PCS Critical Load Metering Point Shunt BESS connection benefits whole plant with voltage regulation during normal operation. Metlak 94.09.19 Power Systems Engineering Power Control Balance of Plant Load Continuous Variation in Active Power By BESS P Closed] Closed p¥ 2 eS (@— 8 Ty Critical Load Metering Point Moderate effects of load swings and impact loads Improve power system stability for remote or weak utility connection Combines active and reactive power supply (voltage support) Energy management, standby power benefits available Metlak 94.09.19 Power Systems Engineering Energy Management Peak Demand Reduction Duration of Peak Shaving asa5300 (kW) Period of Peak Demand Charges Time (of day) Peak shaving with BESS reduces demand charge. Metlak 94.09.19 Power Systems Engineering Utility Demand-Side Management ¢ BESS can satisfy DSM programs by shaving load peaks. ¢ Deferred generation capacity allows utility to postpone capital investment. ¢ Energy is still delivered to load and sold . Power Systems Engineering Isolated Operation of BESS Balance of Plant Load BESS Serves Critical Load Open] Open x | After isolation Critical Load BESS has the capability to serve critical load when isolated. Metlak 94.09.19 Power Systems Engineering Conceptual Comparison of BESS vs Pumped Hydro Remote Urban Area with Generation Local T & D Region Subsystems EHV Transmission b Pumped Hydro *= BESS Potentially Overloaded Line Metlak 94.09.19 Power Systems Engineering Summary « BESS economically provides UPS function in large sizes (1 MW to 40 MW) - BESS provides additional continuous benefits: - Voltage Support Energy Management (Peak Shaving and DSM) - Active and Reactive Power Control Metlak 94.09.19 Tab 7: BESS Case Studies e BESS Case Studies Presenters: Abbas Akhil, Sandia National Laboratories George Hunt, GNB Technologies Nick Miller, General Electric Power Systems Engineering Installation and Commissioning of Vernon 2.5 MW-hour Battery Energy Storage System Nicholas W. Miller GE Power Systems BESS Installation at Vernon, CA e Installed at battery recycling facility. e Environmental and safety considerations require large standby power supply. Ratings of Vernon BESS System Voltage: 4160 V Nominal Current: 348 A Continuous Power: 2.5 MW Overload Rating: 5 MW for 10 seconds 1 hour On-Utility Operating Mode e Normal mode — batteries on standby. e Utility supplies active power. e BESS is charging, peak-shaving, or managing reactive power as needed. ¢ Closed-loop VAR regulator of BESS maintains power factor. * Power order controlled by battery charging and/or peak shaving schedule. Isolated Operating Mode e Relays detect loss of utility tie. e Incoming circuit breaker is opened. e BESS supplies entire plant load for 10 seconds, during which plant control system sheds non-critical loads. e After 10 seconds, BESS supplies up to 2.5 MW of critical load for one hour. Resynchronizing Mode e BESS adjusts voltage, frequency, and phase angle to match utility. e Synch-check relay allows reclose of circuit breaker. e Returns to On-Utility Operating Mode. Batteries e Sealed, low-maintenance valve-regulated lead-acid (VRLA) batteries. e 378 modules x 2V per module = 756 VDC strings. e Two strings paralleled for 2.5 MW-hour capacity. e Battery room measures 104 ft. x 25 ft. BESS Building and Yard Battery Module Stacks Filter Bank e 1400 kVAR outdoor bank e 5th, 7th, 11th harmonic branches e Meets IEEE-519 Std. limits under all operating conditions. Final Commissioning Tests e Loss of Utility Tie e Harmonic Measurements e Motor Starting e Resynchronization Loss of Utility Tie e Plant load at 3000 kW. e Trip incoming breaker manually. e BESS supplied 2100 kW critical load for 30 minutes. Loss of Utility Tie Test *SPD: S mm/s *TIME SCALE: z (a) Battery Voltage (b) Plant Voltage (c) PCS Watts (d) Battery String #1 Current (e) Battery String #2 Current (f) Plant Frequency (g) BESS Line Current at 4160V Bus (includes filter) Harmonic Measurement During Isolated Operation Readings - 11/08/95 14:11:20 Voltage Volts 0 ; : f 10.42 12.51 14.59 -100 -200 Time mS 130 Volts 100 rms 2 °pc 24 6 8 OO Ol ll Oh UC 13 $ 7 9 WoW is 17 19 2 2 2 2 2 3 Harmonic Number Motor Starting e 100 hp motor started while BESS operating in isolated mode. e BESS picks up additional starting current with no frequency or voltage variations. Motor Starting Test *REALTIME RECORDER . x (a) Battery Voltage (b) Plant Voltage (c) PCS Watts (d) Battery String #1 Current ~ (e) Battery String #2 Current (f) Plant Frequency (g) BESS Line Current at 4160V Bus (includes filter) Resynchronizing e BESS supplying isolated plant load at 2300 kW. e BESS control syncs to utility and relay closes circuit breaker. e Immediately following breaker closure, BESS reduces power output smoothly. Resynchronization Test (a) Battery Voltage (b) Plant Voltage (c) PCS Watts (d) Battery String #1 Current (e) Battery String #2 Current (f) Plant Frequency (g) BESS Line Current at 4160V Bus (includes filter) Tab 8: BESS Equipment Overview e Battery e PCS & Controls e Harmonic Filters and Switch Yard Presenters: John Kleba, GNB Technologies Nick Miller, General Electric / | Pp eS KE (SOQ oe GIN|B| Battery Energy Storage System Metlakatla Power & Light - System Rating Base Voltage 12,470 Volts Line to Line BESS Nominal Current 37 Amps RMS BESS Nominal Power 800 KVAcontinuous 1600 KVA10 seconds Number of Battery Strings 1 Battery String Rating 1.00 MW/1.40 MWh Battery Voltage 900 Volts DC maximum 660 Volts DC minimum GIN Bl = CI . ett id 2 wae ae ee ee ee ee | COW eet Nee Metlakatla Power & Light — Battery String ae _ Apree of Fee oor GNB ABSOLYTE IIP Batteries — ot eat Sealed, Valve Regulated Lead-Acid (VRLA) © ©?**> Patented MFX Positive Grid Alloy — Battery Module Type 100A75, 2 Volts dc — One Series String, 378 Modules, Nominal 756 V dc NA ber hens UL 94 V-0 / 28% L.0.1 Flame Retardant Ce i _ Battery Assembly, U.B.C. Seismic Zone IV Requirements Patented Plastic/Steel Composite Mounting Pedestals Operating Range, 662 V dc to 900 V dc Low Maintenance, Long Life, & Deep Cycle Capability Simple Cell Replacement Capability ang mol (a 3 coMs oom / — > 756 %Y. Dc |G|N|B Battery Energy Storage System MP&L BESS System One-Line le Inside Cobe neth 2 DO Rrsey Cabin Item __ Description 1 BESS Power Conversion System (PCP) LL PCS 2000. Control with voltage and power regulation. 1.2 _Zig-zag isolation transformer, 800 KVA, 470 - 12,470 Vac 13) PCP Switchgear with PT's and CT's 2 Battery System eli Battery string, 756 VDC nominal 2.2 Fused DC disconnect switch 3 Control and Monitoring Equipment 3.1 Station control cabinet with sequencing, outer loop and AGC controls Sez Operator panel 3.3 Battery monitor/charge control cabinet and remote sensor cabinets 3.4 Battery monitor PC and Data Acquisition System. 1D PowerTrac for control and monitoring of Centennial diesel 3.6 PC for System Operator Interface System 4 Auxiliary Equipment 4.1 125 VDC station battery with chargers, 2 hr. hold up time for blackstart. 4.2 Auxiliary power transformer with fused disconnect switch 4.3 Master switchgear cabinet, with internal fault relays & filter protective relays 5 Filters 5.1 Common bus filter to meet IEEE 519 5.2 Vacuum switch, CT’s for overload protection Mets v~> 1 wu) ~ ee von = (wow a hep 5. Dow on As ae Smo Lowe Exe Iss un Le aw + G YO" A Bl i . nw 7 occy | ext / Poche (mer - “4 a= 7 l (zs° i oC \s) et : por ot me : 7 vues | leo f “ [b Ou too Naat o& i _ . > unecAcs he Sides of eM > we Co ontoos b ble |G|N|B) Battery Energy Storage System Vernon System Rating Base Voltage BESS Nominal Current BESS Nominal Power Number of Battery Strings Battery String Rating Battery Voltage 4160 345 2800 9000 1.25 900 660 Volts Line to Line Amps RMS KVA Continuous KVA 10 seconds MW/hr. Volts DC maximum Volts DC minimum —o— ~ |@IN|B| Battery Energy Storage System Vernon BESS System One-Line Item Description 1 BESS Power Conversion System Ll PCS 2000 1.2 Zig-zag isolation transformer, .92 MVA, 522 - 4570 Vac < 13 Fused contactor with PT's and CT's _ Limit Amp 2 Battery System F211 Battery string, 756 VDC nominal, 1.25 MW-Hr 2.2 Fused disconnect switch eat3. Control and Monitoring Equipment 223.1 Station control, sequence logic, outer loop controls 3.2 Operator panel 3.3 Battery monitor and DAS 3.4 PSIC (relay panel) with PowerTrac 4 Auxiliary Equipment 4.1 125 VDC station battery with charger 4.2 Auxiliary power transformer 43 Fused disconnect switch with PT's and CT's a Filters ea = 5.1 Common bus filter to meet IEEE 519 5.2 Fused contactor oe inktradic G|N|B| Battery Energy Storage System Power Conditioning System 2000 (PCS 2000) Power Output Rating 1.0 MVA continuous 1.67 MVA 10 seconds 575 Volts AC DC Voltage Input 660 - 900 Volts DC Power Converter Description — Air Cooled — Gate Turn-Off (GTO) Power Devices — 12 Pulse Output Configuration — Microprocessor Based Electronics — User Configurable Programmable Software IGIN/B Battery Energy Storage System Power Conditioning System 2000 (PCS 2000) Capacitor Panel GTO Converter (6 Pulse) Follower DC Line Panel (Contactors) GTO Converter (6 Pulse) Master Tab 9: MP&L BESS Overview e System Operation e Dispatch & Maintenance e Performance Benefits Presenters: Jody Lenihan, P.E., Atlas Engineering FOLLOWER MASTER 470V A LEG: HO-H3 (X) H12—H11 (Y) H1—H2 (Z) MAG, ANGLE FUNDAMENTAL —30 30. 2x @ 0 0 STH HARM. oO —150 150 oO ____MASTER (DEG) FOLLOWER (DEG) 71H HARM. 0 150 -150 0 Tl - 13 180 150 2-71 -60 -90 B LEG: HO-H1 (0 H4-H3 (Y) H5-H6 (2) MAG, ANGLE T3 - 12 60 30 (DEG (DEG) (DEG) et YeteZ FUNDAMENTAL = — 120 —150 -90 2X @ -120 MASTER LEADS FOLLOWER BY 30 DEG FOR STH HARM 120 -30 -390 oO REQUIRED 15kV PHASING AS SHOWN. 7TH HARM. —120 30 90 0 XFMR 1: SEC = 470V_ PRI = 3600V Co Be Ao Cc LEG: HO-H2 iw H8-H7 (Y) —H9-H10 (2) MAG, ANGLE = oN 4 —————————— | RATIO = 7.659 ; FUNDAMENTAL 120 90 150 2X @ 120 XFMR 2: SEC = 470V_ PRI = 2079V . 5TH HARM. —120 90 RATIO = 4.423 (EACH WOG) 15kV_ UTILITY 7TH HARM. 120 -90 0 TOTAL RATIO = 7.659 + (1.732)(4.423) = 15.320 Waa .-G FIFTH AND SEVENTH HARMONIC COMPONENTS EFFECTIVELY CANCELLED. = 12.47kV L-L DIMENSIONS IN INCHES - SCALE TLE | METLAKATLA Pee ae TRANSFORMER CONFIGURATION ENGINEERING DATE ; CUIENT ’ GROUP GENERAL ELECTRIC BATON ROUGE, LA CAD FILE METXFMR PSEC Bl) METXFMR SHEET 1 OF 1 Atlas Engineering Group Inc. BATON ROUGE, LA DATA CALCULATION SHEET CUENT GE PSEC METLAKATLA BESS [SUBJECT BEFORE AND AFTER Xi,73 MATCH TIZZ. IS KV BESS AND UTILITY WAYEFORMS (MEASURED @ PT.S AEG JOB # DATE 1-20-9G ENGINEER PL . PHASOR: A: 13K @ @S5° ot ee Sede > ACCEPTABLE FOR $2-7 GlLOSE:: PHASOR: VOLTS 11K @ 323° Atlas Engineering Group Inc. DATA CALCULATION SHEET BATON ROUGE, LA AEG JOB # DATE I-Z26-37 ENGINEER FL CLIENT GaLwiiesece METLAKATZA BESS SUBJECT BATTERN GROUAD Z LEAK. OSTECTOR.- (Pa 2 OFS) Locks & Usv occur 6 oan KON seam —— | 7 post Cov 16V 16V LEAK AT STACK 1 16V DC DISCONNECT 1 48 LEAK DET, FUSES @ ae <BOTTOM> GF. DET. 3 46 27 22 FUSES <TOP) 4 45 5 44 onet [24 he 6 43 Checks Pp 30 19 a Se | . set iC rent 5 7 42 is wee d 3 is = corer, (f 8 ra pea ter gwtied 32 17 = SSS oh md gout 9 40 yen cont 33 16 { ww 10 39 does nt fle, 34 15 -———___—_ alavwm bapa ut 38 35 14 12 37 36 13 LEAK DETECTION PROCEDURE 1, STOP BESS, OPEN DC DISCONNECT, ON Bf OS REMOVE GROUND FAULT SENSING FUSES ON STACKS 18 AND 24 (TOP). Rovere REMOVE LEAK DETECTOR FUSES ON STACKS 23 AND 26 (BOTTOM). = le drveald DIVIDE BATTERY INTO SECTIONS BY OPENING LINKS TO STACKS 13, 25 AND 36. ¢ MEASURE DC VOLTS FROM BATTERY RACK TO BATTERY TERMINAL. IF VOLTAGE DECAYS '" MW TO APPROX. 2V, NO LEAK IN THIS SECTION, IF VOLTAGE IS CONSTANT, LEAK EXISTS. Saft DETERMINE CELL WHOSE NEGATIVE TERMINAL READS ZERO VOLTS TO BATTERY RACK. € THIS IS DEFECTIVE CELL. REPLACE CELL. RECONNECT BATTERY STRING AND REINSTALL FUSES. VERIFY NO OTHER LEAKS, RESTART BESS. COMMON CAUSES: 1, PINHOLE IN COVER SEAL 2. POST LEAK he ty, Next | | Archive | SER - Sequence of Events Recorder 08/02/97 09:07:13 AM Lower voltage entry for BESS LVBESS 08/02/97 09:07:13 AM Lower voltage entry for BESS LVBESS OFF 08/02/97 09:07:16 AM Lower Voltage at BESS in progress LQ_BESS ON 08/02/97 09:07:19 AM Lower Voltage at BESS in progress LQ_BESS OFF 08/02/97 09:07:29 AM Lower voltage entry for CL LVCL ON 08/02/97 09:07:29 AM Lower voltage entry for CL LVCL OFF 08/02/97 09:07:31 AM Lower Voltage at CL in progress LV_CL ON 08/02/97 09:07:33 AM Lower Voltage at CL in progress LV_CL OFF 08/02/97 09:08:09 AM Execute manual kW order, CL EXP_CL ON 08/02/97 09:08:09 AM Execute manual kW order, CL EXP_CL OFF 08/02/97 09:25:16 AM Raise voltage entry for CL RVCL ON 08/02/97 09:25:16 AM Raise voltage entry for CL RVCL OFF 08/02/97 09:25:17 AM Raise Voltage at CL in progress RV_CL ON 08/02/97 09:25:20 AM Raise Voltage at CL in progress RV_CL OFF 08/02/97 09:25:27 AM Raise voltage entry for BESS RVBESS ON 08/02/97 09:25:28 AM Raise voltage entry for BESS RVBESS OFF 08/02/97 09:25:29 AM Raise Voltage at BESS in progress RQ_BESS ON 08/02/97 09:25:32 AM Raise Voltage at BESS in progress RQ_BESS OFF WY PO:}b:0L =. 26/2/8 “9a O| 193Je sjaoueD —~ -oyne doys / 41S @ \ yey 2LT- » ©1909 © 8 =~ vsre 92T- | el O° @ | juneeoe ZyuN eye aiding COC QD _ @ sawneyrreiains 3NI-430 -SNIT-NO yes paqva = yot—‘“ S - % jonuop = WIOg aqeeAy soured “ snyeys yun — doyg / WEIS UO}BIEUED Eo ' ae os oe EER CSR SER - Sequence of Events Recorder Previous | E Next | |. Archive _ Print 07/27/97 04:58:56 PM BATTERY STRING 1 CONNECTED STRING1 OFF 07/27/97 04:58:56 PM NewAlarm $NewAlarm ON 07/27/97 04:58:56 PM BATTERY STRING 2 CONNECTED STRING2 OFF 07/27/97 04:58:56 PM ON UTILITY (MAIN BESS BREAKER CLOSED) GONUTIL OFF 07/27/97 04:58:56 PM BESS IS RUNNING GBESSON OFF 07/27/97 04:58:56 PM BESS IN CHARGE MODE CHMODE OFF 07/27/97 04:58:56 PM PCP1 READY GPCP1RD OFF 07/27/97 04:58:56 PM PCP2 READY GPCP2RD OFF 07/27/97 04:58:56 PM PCP1 RUNNING GPCP1ON OFF 07/27/97 04:58:56 PM PCP2 RUNNING GPCP20N OFF 07/27/97 04:58:56 PM BATTERY READY GBTRDY OFF 07/27/97 04:58:56 PM BESS IN LOAD LEVELING MODE LOADLEV OFF 07/27/97 04:58:56 PM ONLY ONE BATTERY STRING INSTALLED ONESTRG OFF 07/27/97 04:59:00 PM HistoricalLogging $HistoricalLogg ON 07/27/97 04:59:02 PM Operator $Operator Administrator 07/27/97 04:59:02 PM AccessLevel $AccessLevel 9999 07/27/97 04:59:02 PM LogicRunning $LogicRunning ON 07/27/97 04:59:06 PM BATTERY READY GBTRDY ON Trending (Click on chart to select variables and time. Legend below gives scaling for common signals.) : Print 100.00 80.00 online | 0.00 ; at ; - — a SEE ; ae Jul-31-97. -—-_s Jul-31-97 Sul 31-97 oul si597 ul 318) | Aug-01-97 09:36:00 14:24:00 (19:12:00 = ~=——-00:00:00 00:00:00 ~—~—«<04: 48:00 0s. 100" Tower Voltage OV 22.14V Hydrogen Sensor 0% 100% - Battery Leak/Gnd -500V 500V String Voltage OV 1000V _—_ PilotCell Voltage OV 3.00V — State of Charge 0% 100% Amp-Hours OAHr 10,000AHr String Current -5000A 5000A Temperatures oc 2000 Bess kW/kVars -2500kVA 2500kVA Power Order -2500kW 2500kW Maintenance Print Equalize | : Enable | [Disable | cee ; Automatic Equalize Setup Enter Value Auto- a Last equalize: 5/9/37 : : : f Equalize : Ppaidnight eset J seal : Days until next equalize: 92 Desired day of week (1=Sunday, 7=Saturday) Manual CAUTION: Stop will initiate an immediate discharge Equalize j es (Immediate) Current during discharge 375 Amps Desired interval (days) (30 minimum, 500 maximum) Discharge Test ae 561A Desired string current \ oO =~ : : Start : z : Discharge : & rs Test : Discharge test string current as Anes Discharge test duration “95.5 Hours Ground Fault - Extend Trip Delay by 8 Hours [Extend |} g Hour ( &S™ Extension Total String 1 AHrs, In: | -123127 (J) Enabled Out: 122627 Tab 10: Appendices e Miscellaneous Information ESA ENERGY STORAGE ASSOCIATION Presentation to Battery Storage Seminar Ketchikan/Metlakatla, Alaska August 5-6, 1997 Dr. Philip Symons Chairman, Energy Storage Association ESA ENERGY STORAGE ASSOCIATION To promote the development and commercialization of competitive and reliable energy storage delivery systems for use by electricity suppliers and their customers. Energy Storage for Electricity Suppl Chronology of Recent Events in US Crescent EMC 500kW/500kWh Peak Shaving BESS SCE (Chino) 10MW/40MWh Load Leveling BESS Utility Battery Group (UBG), 8 founding utilities SDG&E 200kW/400kWh Transit Peak Shaving BESS PREPA 20MW/14MWh Spinning Reserve BESS, GNB (Vernon) 5MW/3.5MWh Reliable Supply BESS ESA incorporated ((trade association) by UBG Steering Committee; Executive Director chosen Oglethorpe/Homerville EMCs 2MW/10 sec. PQ BESS Metlakatla P&L 1.2MW, 1.2MWh Voltage Support BESS 30+ Members in 1997, including: Electricity Providers (11) Equipment Manufacturers (11) Research & Consulting (7) Institutional Funders (3) Members elect Board of Directors Board selects Executive Director ES4 1996/7 Meetings e Amelia Island, FL: November 1996 Power electronics and Power Quality ¢ Washington, DC: May 1997 Renewables and Energy Storage e Sacramento, CA: November 1997 Utility Restructuring and Energy Storage ESA 4997 products Monthly fax newsletter: Update on energy storage news and opportunities ESA Website: Public Access and Members Only sections ESA Fact Sheets: Information on ongoing energy storage projects ESA Literature/Presentations: Promote benefits/applications for energy storage ES4 COORDINATION ACTIVITIES ENERGY STORAGE ASSOCIATION e ESA coordinates with other US and International organizations with projects in or related to energy storage e Examples: Earth Day congressional breakfast, IEA Annex IX, NWPPA, SEIA e Responsibility of Executive Director (primarily) and Member representatives (as needed) Battery Energy Storage - The cornerstone of electricity supply for the 21st Century Enhanced Stability Better dispatchability Battery Improved Energy reliability S) Co) g-[e [=] Deferred generation expansion ES.4 ENERGY STORAGE ASSOCIATION VISION Energy storage systems achieve commercial acceptance by electricity suppliers and customers resulting in viable products and markets. ESA ENERGY STORAGE ASSOCIATION Energy Storage Advanced Power Management Technologies for a New Electricity Era ENERGY — Advyva Tae to Pe © PACS ee eke ee tl (nO eas eal CGPS Pope WéSiare allffimiliar with storage devices such as batteries which have been used for decades to provide portable electricity supply in millions of automobiles, appliances, and electronic devices. And, since the 1930s, electric utilities around the world have employed pumped hydro- ctric storage to meet fluctuating demand. Despite these experiences, there is still the common perception that bulk electricity storage for utilities is not practical. But now a new generation of smaller, modular energy storage technologies are emerg- ing. These new systems offer tremendous value and opportunities for both electric- ity providers and users. Electrical energy can be either stored directly or converted and stored in differ- ent forms such as chemical, mechanical, or potential energy. The stored energy can be quickly converted on demand and used in a wide variety of electric applications and load sizes. Advancements in battery technology, superconducting materials and flywheels have resulted in systems that can now provide reliable power on demand and with reduced capital investment. Because of the modularity of distributed energy storage, additional benefits are gained from their strategic placement within the electric network. | Types of Energy Storage © Batteries © Compressed air © Flywheels © Pumped hydroelectric © Supercapacitors © Superconducting magnets The first modular battery storage system was developed in a partnership with the U.S. Department of Energy/Sandia National Laboratories and the AC Battery Corporation and tested at Pacific Gas, & Electric’s San Ramon test facility. G@mpetition to Provide Electricity The USS. electric utility industry, a regulated monopoly since its inception at the turn of the century, is undergoing a massive restructuring that will result in significant changes as well as opportunities for emerging technologies. The creation of competition in wholesale and retail electricity markets will result in new products and services such as premium power, energy supply contracts, electricity commodity futures, and green power. Distributed energy storage technologies have matured to the point of gaining industry and investor confidence. More than 70 megawatts (MW) of battery storage (enough power to start half all of the cars in the each day) have been installed by utilities and their cus- tomers to provide ancillary transmission services, premium power quality, and to firm intermittent renewable resources. Superconducting magnetic energy storage (SMES) devices are being leased or sold around the world to provide instantaneous premium power quality for electricity both domestically and internationally. As developing countries continue to upgrade and expand electric supply, energy storage systems are being used to facilitate economic development. At least four U.S. firms are developing flywheel (electro- mechanical) storage products which initially will be marketed for power quality and unin- terruptible power supply applications. c__ Energy Storage Manufacturers and Customers gy Bett et le Power Administration World Flywheel Connortnay Tr AC Warery Corporation Superondaciviy Ine oe 5 BBN Techno Manicipal Uy Die Come (le = * Sat Hear Fact in Operation & Tae Uiidet Eta (racine \ TS oeyr tess GD cet nnd 2 te eter Hawsian Electr as tele Mantes Medaka Village Medaka Powe! and Light + Kanaan Vil Thangit Haids Regional Electric Authority Energy Storage Provides Many Benefits for US Economy Pee Tay MO Dae MC) aL LO LO RL) gies. Energy storage is one of those critical technologies and will create new busines TO Oy ee ee LL CO RL Le La A reliability reserves. Market projections for energy storage are likely to result in: Installation of 900 MW annually of energy storage devices by 2010 Productivity improvement for US industrial sector of $150 billion annually Markets exceeding $1 billion by 2010 resulting in 7,000 new high-technology manufacturing CL Ran Lem Enhanced renewable energy market penetration by 2010 with concomitant emissions savings of 250,000 metric tons of carbon Emerging high-technology leadership with export market potential to exceed $500 million annually by 2010 Energy Storage offers exciting opportunities for researchers, product manufactures, electricity providers, and electricity customers. To learn more about these opportunities please contact: ESA Energy Storage Association 4733 Bethesda Avenue Suite 608 Bethesda, MD 20814 Phone: 301-951-3223 Fax: 301-951-3235 This document was prepared by the Energy Storage Association in collaboration with the Solar Energy Research and Education Foundation. Support for this document was provided by the Energy Storage Systems Program of the U.S. Department of Energy with program management and oversight provided by Sandia National Laboratories. ergy Storage Applications Managing Power for an Island Economy The Puerto Rico Electric Power Authority (PREPA), the island’s utility, determined that a battery energy storage system would be the most cost-effective option to meet the island’s unique circum- stances. Four 400-MW oil-fired units were added (nearly doubling PREPA’s generation capacity) during the 1960s and 1970s when Puerto Rico experienced rapid demand growth. When growth stagnated after the 1979 oil crisis, PREPA recognized that an unscheduled shutdown of a 400-MW power plant caused electrical overload of generators that remained on line. As a result, standby generation could not reach full speed during the critical first seconds. The only other option, load shedding, caused blackouts and negated the economy of scale that originally justified con- struction of large generating plans. After a thorough analysis, PREPA installed 20 MW of battery storage at Sabana Llana, a 115-kV substation. PREPA is planning another 20 MW energy storage system which will allow the utility to make the most efficient use of existing generating capacity and provide reliable service to their customers. Economical Solutions for Village Power A sawmill constitutes a large portion of the demand for the 8.0 MW combined hydro and diesel generation capac- ity of Metlakatla (Alaska) Power and Light. Other village customers include residences and commercial loads. The mill’s heavy motor loads caused substantial fluctuations in both system voltage and frequency and a 3.3 MW diesel generator was required to satisfy response rate require- ments. The recent addition of a 1 MW battery energy storage system allows Metlakatla Power and Light to adjust to fast power swings without using the diesel generator. The battery storage system also means less money spent for diesel fuel and less risks associated with fuel handling and environmental clean up. Maintaining Critical Safety and Environmental Operations bed Many industrial and commercial users face substantial losses = (% 3 . due to momentary or sustained power interruptions. The GNB Lead Reclamation Facility in Vernon, California, recently installed a battery energy storage system rated at 3.5 MW for one hour to supply uninterruptible power to ensure the plant’s critical loads are met. One of the most critical processes is the operation of the plant's emission control systems. The storage system allows GNB to ensure that possible emissions are avoided even if electrical power is interrupted. Us EO enn EA ee RCE he value of energy storage lies in its flexibility, reliability and the strategic benefits it offers to its customers. Both electric utilities and consumers can incorporate energy storage to provide premium services (power quality or uninterruptible power, for example) or to take advantage of flexible rates by discharging the stored energy when rates are the most expensive and charging the system when electricity is inexpensive. Utilities can incorporate large-scale energy storage as load leveling facilities to maximize their return on investment by improving plant capacity factors. Special applications for energy storage are either grid-tied or grid-independent renewable energy systems. The emergence of renewable energy, especially wind and photovoltaics, has created broader market opportunities for energy storage. Whether buffering and firming the resource variation, or by matching the resource availability to the peak load and obtain the highest price for electricity, energy storage can enable greater use of renewable energy. What Makes an Energy Storage System? Generally four components are included in a typical energy storage system: * — Storage device such as a battery, supercapacitor, superconducting magnet coil, or rotating mass (flywheel) * Power electronics to convert utility electricity (AC) into stored energy and back again * — Control system to receive signals from the user and direct the electronics when to turn on and off ¢ Building or structure to house the components and protect them from the weather These components together are offered as a packaged system and are referred to as an energy storage system. Joint efforts between the U. S. Department of Energy/Sandia National Laboratories and the private sector are primarily focused on optimizing the output and compatibility of individual com- ponents into packaged systems. Fully integrated, reliable energy storage systems are critical to meet the needs of energy consumers and providers in a new electricity era. Distributed energy storage has become an important ally with state-of-the-art renewable energy technology. Dangling Rope Marina on the northern shore of Utah's Lake Powell was powered solely by diesel generators operated by the Glen Canyon National Recreation Area at an average cost of $.38/kWh. In 1996, a solar photo voltaic system, two propane-fueled engine generators, a battery system of 2.4 MWh, and a hybrid power con- verter were installed to replace the diesel system. The result is a savings of $100,000 per year as well as a sig- nificant reduction in noise and air pollution. Lightning is a frequent visitor to Homerville, Georgia, often causing power disturbances to the local litho- graph plant, a major employer in this small rural com- munity. The Slash Pine Electric Membership Cooperative (SPEMC) and Oglethorpe Power Corporation, the local power providers, recognized that the occurrence of frequent short circuit faults on the utility's transmission and distribution systems caused by storms, falling lines and small animals were impacting their customer's operation. The search for solu- tions to these problems resulted in a collaboration between SPEMC, Oglethorpe, and the Electric Power Research Institute. As a follow-on to a US Department of Energy/Sandia National Laboratories research and development effort, they purchased and installed a battery storage system from AC Battery Corporation in 1996 that has improved power quality resulting in increased pro- ductivity and safety for the plant. This productivity enhancement is helping to ensure the plant's continued existence and expansion TEV MCR ena lags BICC) xe aaa TAC a emt “Voltage support “Power quality “Peak Shaving “Optimize renewable energy systems For Distribution Feed ace) Sur eR “Voltage support em rN) For Transmission Networks/Substations “Increase Power Flow rl aa aU aay Mic Surg TUTer UCI BY Ce MTA NCae Tec m amc C MTC RCI “Operating (Spinning) reserve TUN ae eel Developers and Organizations Nidiidamanataeedieie maaan ag) Arizona Public Service (AZ) Detroit Edison (MI) National Power (UK) Crescent Electric EMC (NC) Northern States Power (MN) Oglethorpe Power Corporation (GA) Ontario Hydro Technologies (Canada) Pacific Gas & Electric (CA) Pacificorp (OR) Potomac Electric Power Company (DC) Salt River Project (AZ) Southern California Edison (CA) Southern Company (Georgia Power) (GA) Tampa Electric Company (FL) Engineering / Consulting Companies The Brattle Group (MA) Decision Focus, Inc. (CA) ECG Consulting Group, Inc. (NY) Electrochemical Engineering Consultants, Inc. (CA) Energetics, Inc. (MD) SENTECH, Inc. (MD) SVS, Inc. (NM) ATG clea cag) POR ccs Ou selena. AD) C&D Charter Power Systems (PA) Delphi Energy & Engine Management Systems (General Motors) (IN) Exide Electronics (NC) GE Drive Systems (VA) GNB Technologies (IL) Intermagnetics General (MA) Omnion Power Engineering (W1) Precise Power Corporation (FL) SAFT America (GA) Silent Power Systems (PA) Superconductivity, Inc. (WI) Trace Technologies (CA) Yuasa-Exide (PA) ZBB Technologies (WI) Tbs are anys Electric Power Research Institute (CA) tara mel tmatreertecer mG) BD) Energy Storage Technology Institute (TX) International Lead Zinc Research Organization (NC) Sandia National Laboratories (NM) Solar Energy Industries Association (DC) DESIGN AND COMMISSIONING OF A 5 MVA, 2.5 MWH BATTERY ENERGY STORAGE SYSTEM N.W. Miller (SM), R.S. Zrebiec (NM) R.W. Delmerico (M) GE Power Systems Engineering Department Schenectady, NY 12345 USA Abstract - Momentary and sustained power interruptions are some of the most difficult and important power quality problems facing many industrial and commercial users. Battery energy storage systems (BESS) have the potential to provide versatile solutions to this problem for utility, industrial and commercial applications. This paper describes the design and commissioning of a 5 MVA, 2.5 MWh BESS which is now in operation at the GNB Battery Recycling Plant in Vernon, California. The BESS at Vernon provides the required power combined with both voltage and frequency control to allow the plant to tolerate disconnection from the utility grid without suffering unacceptable impacts on critical loads. INTRODUCTION A 5 MVA, 2.5 MWh Battery Energy Storage System (BESS) was placed in service at the GNB Battery Recycling Plant, Vernon, California in November, 1995. The primary function of the Vernon BESS is to maintain the critical process loads during outages resulting from disturbances external to the plant. To accomplish this, it is installed at the 4160V level of the plant power distribution system, in parallel with the existing loads. The BESS is designed to work with the existing plant control system to automatically shed all non-critical loads as soon as possible after an incident. This permits the critical loads of up to 2.5 MW (mostly large induction motors) to operate for up to one hour. This time is necessary for the plant to safely shutdown its critical processes. Provision is made for transfer back to the utility feed if utility power is restored before the end of the one hour period. A secondary function of the system is to reduce the plant demand charges. This is accomplished by utilizing a portion of the battery capacity to supply energy to the plant during peak load periods. G. Hunt (NM) GNB Industrial Battery Lombard, IL USA This paper will provide an overview of the converter and battery system and show key test results obtained during commissioning at Vernon. A detailed description of the converter design is planned for future publication. OVERVIEW OF THE INSTALLATION The system consists of the following major items: 1. A dedicated Battery Energy Storage System building. 2. Two strings of batteries, complete with manual disconnect switches and fuse protection. 3. Battery monitoring control cabinet providing peak shaving and state-of-charge control. 4. Personal computer interface to the battery monitor for data display, battery maintenance and data acquisition. 5. A power conditioning system (PCS), which provides bi- directional power conversion between the ac and dc systems. 6. Station control for sequencing and control of the power converters. 7. Remote operator’s panel located in the plant control room. 8. Fused main BESS disconnect switch. 9. Power factor correction capacitors and harmonic filter to meet IEEE 519. [1] 10.Relay panel responsible for detecting a utility outage and supervising the operation of the main plant service breaker. Three key modes of operation exist: ¢ On Utility — which defines the normal state when active power for the plant loads is supplied by the utility and the BESS is idle, charging or peak shaving and managing reactive power for the plant. e Isolated —- which defines the emergency state when power for the plant loads is supplied by the BESS and the utility is disconnected. e Resynchronizing - which defines the process whereby the isolated plant is reconnected to the utility. A simplified one-line diagram of the system is shown in Fig. 1. Battery System = __| Battery = Monitor l | Personal | Computer CO Ld PCS — Station de Control ¥ ¥ Remote Operator's ww Panel BESS Disconnect Critical Loads Plant ____ peey Breaker a” 4160V Utility Feeder Fig. 1. Simplified BESS One-Line Diagram. The entire Vernon BESS, including the batteries is enclosed in a 131’x25’ building with the filter, transformers and disconnect switch located outdoors. The battery building is shown in Fig. 2. System Rating The system is designed to operate for 10 seconds at a maximum plant demand of 5 MVA immediately after the transition to isolated mode. This capacity exceeds the total existing and projected loads at the plant with some margin. Upon sensing a loss of utility voltage: 1, the incoming circuit breaker is opened, 2. the existing plant control system will shed all but the critical load, and 3. the BESS will carry the critical loads, up to 2,500 kW for one hour. SUMMARY OF SYSTEM RATINGS FOR GNB VERNON Base Voltage 4160 Vrms L-L Nominal Current Rating 348 Arms Nominal Power Rating 2500 kVA continuous 5000 kVA for 10 sec Nominal DC Voltage Rating 756 Vde (660 - 900 Vde range) Power Conditioning System The PCS part of the BESS consists of a voltage source inverter which is designed to operate as either an inverter when discharging the battery or as a rectifier when charging. The PCS is designed with self-commutating static switches capable of supplying the reactive power needs of the system.[2] The ac waveform has some resultant harmonic content which is filtered to meet IEEE 519 standards. The 6-pulse converters of the PCS are arranged in pairs. A simplified circuit diagram of one Power Converter Pair (PCP) is shown in Fig. 3. Each PCP forms a 12-pulse, PWM, bi-directional, voltage source GTO converter. Each GTO is paralleled by a reverse diode to give the converter the capability of handling power flow in both directions. The de capacitor, CD, is necessary to absorb ac currents reflected by the converters on to the de bus. Fig. 2. Vernon Battery Building. 2 Phasor Diagram 2c 28 N 1A 2A ——_ Transformer Type 1 1A Transformer Type 2 5 + ae ae a AY + d| l ° aI cD Fig. 3. 12-Pulse Power Converter Pair. Each 6-pulse converter is connected to a power transformer designed for static converter operation. The connections are arranged to provide an equivalent 12-pulse wave shape when connected to two 6-pulse converters operated with firing signals 30 electrical degrees apart. Three PCPs are connected in parallel to achieve the rating requirements for this application. Each PCP is connected to the power system through an ac contactor. The PCP converter hardware is shown in Fig. 4. The two 30” wide cabinets on the right hand side contain the two 6- pulse GTO converters. The upper half of these cabinets contain the drive control hardware. The GTO bridge, gate drivers, blowers and energy recovery snubber circuit are mounted in the bottom half. The center 24” wide cabinet contains the de link capacitor bank (CD) and protection. The left hand cabinet is the application specific dc line panel. This panel includes the de link converter, capacitor charging circuit, V/O interface, control isolation transformers and miscellaneous control hardware. Theory of Operation For most operating conditions the BESS is equivalent to a voltage source behind the transformer reactance (X77) as shown in Fig. 5. The PCS generated voltage (Vg) is completely controllable within the current rating of the converter equipment. Consequently, the ac current can be supplied at any phase-angle relative to the terminal voltage (V7). This feature permits the BESS to generate real and reactive power in all four quadrants as indicated by the capability curve. The BESS power generating capability is limited by the thermal rating of the converters and the available battery voltage. Overload capability will permit operation at higher currents for limited periods of time, as suggested by the dotted capability curve. DC Line Panel DC Link Capacitor 6-Pulse Converter 6-Pulse Converter Fig. 4. PCP Converter Hardware Line-Up. Reactive Power (kVAr) Rated | — Converter 2 = Overload Capacity N\, ‘7 Capacity \ Active Power (kW) Charging » ‘Discharging Inductive Equivalent Circuit VB x. O na YT Distribution oops Network IT Phasor Diagram “B was i VT , Fig. 5. Active and Reactive Power Capability. A simplified block diagram of the control system is shown in Fig. 6. Terminal voltage magnitude and power control loops are included with the PCS. Power and voltage orders are provided by the Station Control. Station Control Control of the PCS to meet the various modes of operation is provided by the station level control as shown in Fig 6. The control consists of a microprocessor controller for regulator functions and a PLC for sequencing and protection. When operating on-utility the voltage order is derived from a closed loop var regulator which maintains the PCS at a desired power factor. The power order follows the charging i Station Control needs of the battery or the operator can schedule the system to automatically reduce the plant demand charges. When isolated from the power grid the voltage order is adjusted to maintain nominal plant voltage (4160V) and the power order is dynamically adjusted to hold rated frequency (60 Hz). When resynchronizing, voltage order is adjusted to match measured utility voltage and plant frequency is adjusted to match measured utility frequency and __phase-angle. Synchronizing with the utility is supervised by a standard synchronism check relay. Battery Monitor Control The battery monitoring control functions: performs five major 1. calculates the state-of-charge of the battery, provides for battery charging and discharging control, monitors the health and status of the battery, yn - records battery operation for future optimization and warranty management, 5. detects ground faults. The Battery Monitoring function is implemented in a PLC, working with the Operator Interface Computer. The computer consists of an industry standard PC running a graphical interface program for data storage and display. Batteries Valve regulated lead-acid (VRLA) maintenance-free batteries are used. Two battery series strings are connected in parallel to provide a nominal amp-hour rating of 2.5 MW- hour. Each string includes a fused disconnect sized to allow operation with one string out-of-service. The electrical center of each battery string is high resistance grounded. A string consists of 378 modules, each rated 2V and connected in series to make a nominal 756V string. The modules are arranged in stacks. A single stack of batteries consists of eight modules separated and supported by 4' steel “T’ beams. Each module measures 42.5” x 26.4” x 8.6” for an / PCP #3 \ / PCP #2 \ / Measured PCP #1 (\ \ Power | Charge [| | poet | ; Power Reg. Angle Control Phase Reg. Measured Mode | are) ; | | Frequency Selector @ | + | G6(s) | Battery ae Frequency Reg. | | PWM } Monitor : Fi | Corel | Selector | GA(s) | i | | 1.0 | Logic | VAR Voltage | 2 | | Control | | 7 VAR Reg. Magnitude | | Magnitude Voltage Reg. with | | Voltage Reg. | Voltage | Reactive Current Droop } | 7 ans) ; | Order | z | | —> | | Measured + G5(s) | + +{ a Voltage | Magnitude } \ VARS Vottage_T Mode Reference Selector Fig. 6. BESS Control System. 4 overall stack height of about 6'. Each stack assembly has a standing weight of about 6360 Ibs. A total of 48 stack assemblies arranged in two rows are required for each string. A typical stack assembly is shown in Fig 7. Fig. 7. Close-up of Battery String. Filter The 1400 kvar filter is sized to correct the critical plant load to unity power factor. The branches are tuned to the Sth, 7th and 11'> harmonics. The filter is designed to meet IEEE Standard 519 [1] under all operating conditions. The BESS may be run in isolated mode without the filter. Relay Panel This panel consists of standard utility grade protection relays designed to monitor the point of utility connection. The control logic will trip the main plant breaker if the utility feeder is faulty. The following conditions are detected: e Faulted phase detection e 3-phase power interruption ¢ |-phase power interruption ¢ Over/ under frequency While the plant is isolated the relay panel will detect when three-phase utility feeder voltage is restored. If the operator then requests a resynchronization, the relay panel will supervise the breaker closing using a synchronism check relay. All relays are self resetting to allow for unattended automatic operation. FINAL COMMISSIONING TEST RESULTS Acceptance tests of the Vernon system were completed on November 5, 1995. The tests included a total interruption of the utility power feeding the plant. The critical plant loads, totaling 2100 kW, were transitioned to the battery system and ran in isolated mode for about 30 minutes. The plant loads were then automatically resynchronized with the utility feeder. The critical load consists of about 25 induction motors plus lighting and control. Four of the motors, totaling 1600 hp, are connected at the 4160V bus. The balance of the motors, about 1400 hp, are connected at 480Vac. Fig. 8 is an oscillogram which shows the response of the system during the breaker trip test. The battery was initially charging at a low rate corresponding to about 480 kW. While “SPD: S mm/’s *TIME SCALE: =z : 20:00 KW: Es: “ (Charging) O. Fig. 8. Response of BESS and Plant During Isolation from the System. (a) Battery Voltage (b) Plant Voltage (c) PCS Watts (d) Battery String #1 Current (e) Battery String #2 Current (f) Plant Frequency (g) BESS Line Current at 4160V Bus (includes filter) charging the BESS is also compensating the reactive component of the plant load to maintain unity power factor at the point of utility connection. This is done to maximize the power available for charging the battery. The total reactive compensation while charging, including the filter component, is about 2200 kvar. The total plant load prior to the test is about 3000 kW (excluding the BESS charging kW) and includes about 2100 kW of critical loads. To simulate a power interruption the plant breaker was manually tripped. Notice that the critical plant loads immediately transition to the BESS following the manual breaker trip. To support these loads the battery string current increases to about 1300 amperes and the battery voltage drops slightly. Since the BESS regulators maintain the proper voltage magnitude and frequency the power output naturally follows the needs of the plant loads. From the plant perspective the breaker trip test was essentially bumpless. All critical loads including sensitive electronic equipment such as PCs were unaffected by the transition. A plot of the measured voltage waveform and harmonic content while the plant was isolated is shown in Fig. 9. *REALTIME RECORDER s a): Readings - 11/08/95 14:11:20 Voltage 100 Volts or 10.42 12.51 14.59 -100 a Time mS 150 Volts 100 Tms %0 SeAiivite Fig. 10. Response of BESS and Plant During Motor Starting. Spc 2° 4 6 8 0 COGS SBS (a) Battery Voltage MS Se 99 10 13) 151 17! 49:1 28.28 98129) 99) 81 (b) Plant Voltage Harmonic Number (c) PCS Watts (d) Battery String #1 Current Fig. 9. BESS Voltage Waveform and Harmonic Content Measured During (e) Battery String #2 Current Isolated Operation. (f) Plant Frequency (g) BESS Line Current at 4160V Bus (includes filter) Motor Starting Resynchronizing While the plant was isolated a 100 hp motor was started. An oscillogram of this test is shown in Fig. 10. The test proceeded without difficulty. Once utility feeder voltage is present the BESS may be requested to reconnect the isolated plant load with the utility. Resynchronizing requires that the instantaneous voltage across the open plant breaker be reduced to zero. To accomplish this the isolated plant voltage magnitude, frequency and phase- angle are adjusted to match the utility. The breaker is closed if the voltage is within +10% and +6° for a two second period. An oscillogram of the resynchronization test is shown in Fig. 11. The isolated plant load at the time of the test is about 2300 kW (the plant loading is increased slightly during the test). The battery voltage before resynchronization is about 740V and the string current is about 1550 amperes. Immediately following the breaker closing the BESS output power is reduced to smoothly transition the plant load back to the utility feeder. SUMMARY This installation is commissioned and performing well. Although the primary function of the Vernon BESS is to maintain the critical process loads, the system will also serve as a demonstration of the practicality of the BESS technology to power quality problems. [3] ACKNOWLEDGMENTS The authors wish to recognize the contributions of W. Hill, C. Harbourt and D. Wanner (converter design), C. Wegner and M. Cardinal (system software), and M. Jesko (battery system). The authors are grateful to these and many others whose contributions are essential to a project of this magnitude. REFERENCES {1] IBEE Std. 519-1992, “IEEE Recommended Practices and Requirements for Harmonic Control in Electric Power Systems,” IEEE, NY, NY, April 12, 1993. (2) L.H. Walter; “10 MW GTO Converter for Battery Peaking Service,” IEEE Trans. Ind. Appl., Jan/Feb. 1990, Vol. 26 #1, pp. 63-72. [3] N.W. Miller, R.S. Zrebiec, R.W. Delmerico, G. Hunt; “Battery Energy Storage Systems for Electric Utility, Industrial and Commercial Applications,” Proceedings PCIM/Power Quality/Mass Transit 1994. S mm/s *TIME SCALE: 200.0 Fig. 11. Response of BESS and Plant During Controlled Resynchronization with the Utility Grid. (a) Battery Voltage (b) Plant Voltage (c) PCS Watts (d) Battery String #1 Current (e) Battery String #2 Current (f) Plant Frequency (g) BESS Line Current at 4160V Bus (includes filter) Design and Commissioning of a Valve-Regulated Lead-Acid Battery Energy Storage System for Backing Up Critical Environmental Loads 5th European Lead Battery Conference - Barcelona, Spain George W. Hunt : GNB Technologies Lombard, Illinois USA ABSTRACT - Momentary and sustained electrical power interruptions and voltage depressions represent two of the most difficult and important power quality and delivery problems facing many industrial and commercial users. There is a definite need at many industrial processing plants and commercial users of electrical power to have a dependable, efficient and controllable source of real and reactive power which is available instantly to support large electrical loads (greater than 0.5 MVA) even if the incoming utility AC connection is lost. When power is interrupted or lost, the results can be extremely disruptive for critical processes resulting in lost production, costly downtime and loss of customer good will, and in certain indus- tries, can lead to environmental damage through the release of toxic emissions into the air. Recently, this challenge was faced by GNB Technologies at its lead reclaiming and smelting facility in Vernon, California. This paper describes a versatile, cost-effective, workable solution to the problem resulting in the design and installation of a5 MVA, 3.5 MWh Battery Energy Storage System which provides uninterruptible power to the critical environmental control equipment throughout the plant. The BESS at Vernon provides the re- quired power combined with both voltage and frequency control to allow the plant to tolerate disconnection from the utility grid without suffering unacceptable impacts on critical loads. The system also provides the company with a demand side energy management system for conducting daily peak shaving of energy demand, thereby reducing its electrical bills. Exhibit 1. Battery Energy Storage System in Vernon, CA, USA INTRODUCTION Battery Energy Storage is a technology that can play a flexible, multi-functional role in a wide range of electric utility systems or industrial manu- facturing and processing applications. A Battery Energy Storage System (BESS) has the potential to offer electrical utilities and/or their customers an effective tool in helping to manage their elec- tricity generation and delivery needs, provide con- servation through energy management and help solve power regulation problems. The basic concept of a BESS is to allow the user to store electrical energy for dispatch at a time when its use is more economical, strategic, or ef- ficient. The battery system normally accepts elec- tricity from the utility grid during off-peak hours when the cost of energy is low, stores it in batter- ies, and returns it to the grid during the peak hours of the day. The battery system can also supply the electrical loads on demand when required, re- sponding very much like an uninterruptible power supply. To perform these functions, numerous com- ponents in the system must work together. The primary components are the power-conditioning system, which interfaces between the utility AC and the battery DC power where the energy is stored, the battery system, an assembly of series and parallel strings of typically 2 - volt lead-acid battery cells, and the controls and monitoring sys- tem. A new generation of battery energy storage sys- tems is now available in power ratings ranging from 0.5 MW up to as large as 40 MW. The capac- ity of the system can be sized to support a few minutes of operation or operate for hours at maxi- mum power. Sizing of a system is driven by the type of application and how it will be used. Why a BESS at Vernon One of the critical processes at the GNB lead rec- lamation center is the operation of emission con- trol systems associated with handling lead dust The plant operates 24 hours per day, seven days per week, and produces over 100,000 short tons of reclaimed lead annually. GNB’s primary con- cern is to assure the continual operation of its en- vironmental control systems during a power in- terruption or complete outage. When incoming power is lost, large fan and blower motors rang- ing up to several hundred horse power stop run- ning and the exhaust emissions from blast and reverb furnaces as well as lead dust generated dur- ing breaking of old spent lead-acid batteries can escape into the atmosphere. A cost-effective, workable solution was found by GNB, resulting in the installation of a BESS that provides uninterruptible power to the critical loads at the plant. Since the critical loads at the plant are not isolated, it is necessary to carry the entire plant load (maximum of 5 MVA) for a short period of time immediately following an incident until non- critical loads have been automatically shed. Plant loading typically peaks at 3.5 MVA with the criti- cal loads totaling about 2.1 MVA. The critical loads are mostly large induction drive 4160V AC mo- tors. It has been established that the plant needs at least 20 minutes of uninterruptible power to ef- fectively control critical processes for a safe and orderly shutdown, thereby, assuring full control of all potential lead emissions. In November 1995, following 12 months of de- sign and construction, the GNB Vernon BESS fa- cility was commissioned and was placed in ser- vice. Vernon BESS Description The primary function of the system is to maintain the critical process loads during outages resulting from disturbances external to the plant. To accom- plish this, the BESS is installed at the 4160V level of the plant power distribution system, in parallel with the existing loads. The BESS is designed to work with the existing plant control system to automatically shed all non- critical loads as soon as possible after a power failure. This operation occurs ina matter of seconds, thereby reducing the overall plant load- ing to approximately 2.1 MVA. The battery ca- pacity has been sized to support up to 2.8 MVA for up to one hour. To support all the critical loads, the plant needs at least 20 minutes for an orderly shutdown. The battery system has been designed with an additional reserve capacity to handle daily peak shaving of 500 kW for 3 hours (1.5 MWh). This added feature allows the system to reduce the plant’s demand and energy costs. Provision is made in the microprocessor-based BESS controls to transfer the plant back (automatically or manually) to the utility feed if utility power is restored within the one hour operating time frame allotted for sup- porting the critical loads. The best way to describe the Vernon BESS facil- ity (Exhibit 1, photo) is to list all the major items and components that make up the system (Exhibit 2, list) and provide the reader with a simplified BESS one-line diagram of the installation (Exhib- its 3 & 4, outline). The entire system, excluding the transformers, harmonic filter bank and coils, and disconnect switch, which are located outside within a fenced-in yard, are enclosed within a building that measures 131 feet long by 25 feet wide. The switch yard area is about 40 feet wide by 50 feet long The building principally houses the battery strings, power conditioning system, controls and monitoring equipment with the HVAC system on the roof. Exhibit 2. List of Major BESS Components 1. A dedicated prefab insulated steel building. 2. A poured 8 inch (minimum) steel reinforced concrete foundation and floor. 3. Two strings of valve-regulated lead-acid bat- tery cells connected in parallel with manual disconnect switches and fuse protection. Each string has 378 2 - V modules connected in se- ries and is fused at 4,000 amperes. Each string is split into three sections (252V each). 4. Battery monitoring control cabinet providing state-of-charge control and peak-shaving con- trol. 5. Personal computer (486 / 66 MHz) interfaced to the battery monitoring control cabinet for data display, battery maintenance, and data acquisi- tion and storage. 6. A Power Conditioning System (PCS) which pro- vides bi-directional power conversion between the utility grid and plant substation AC systems and battery DC system. 7. Station control for sequencing and control of the power converters. 8. Remote operator’s panel located in the plant control center. 9. Fused main BESS disconnect switch. 10. Power factor correction capacitors and harmonic filter to meet IEEE 519 standard. 11. Relay panel responsible for detecting a utility outage and supervising the operation of the main plant service breaker. 12. Separate PCS and battery room heating, venti- lation, and air conditioning units (HVAC). BESS Performance Criteria at Vernon There are two types of disturbances that the BESS guards against. These are power interruptions and short circuits. A power interruption is the loss of one or more lines feeding the plant. Since the BESS acts as a voltage source in parallel with the load, the load will not experience the interruption and will continue to operate normally. The plant breaker will open based on measured current in-balance or reverse power flow. Short circuits can occur as phase-to-ground or phase- to-phase and will affect the entire plant. The strategy for dealing with short circuits is to isolate the plant from the fault and reestablish voltage to the loads as quickly as possible in less than 200 milliseconds. The BESS is designed to continue to operate through these short circuits. After the plant breaker is tripped, a signal is sent to the plant load center to trip non- critical loads and restart some critical loads, if nec- essary. The BESS can be set to automatically re-syn- chronize and connect to the utility when power is restored provided the MWh rating of the battery system has not been exceeded. By design, there are three modes of operation that exist: on utility, isolated, and resynchronizing. x On Utility - defines the normal state when active power for the plant loads is supplied by the utility and the BESS is idle, charg- ing or peak shaving and managing reactive power for the plant. x Isolated - defines the emergency state when power for the plant loads is supplied by the BESS and the utility is disconnected. x Resynchronizing - defines the process whereby the isolated plant is reconnected to the utility grid. Exhibit 3. Vernon BESS One-Line Diagram Exhibit 4. Description of Major Components — — lo iS car ieee, one NO eS) 3.4 4.1 4.2 43 eh ey? Description BESS Power Conversion System General Electric PCS 2000 Zigzag isolation transformer, -92 MVA, 522-4270 Vac Fused contactor with potential trans- formers and current transformers, (PT’s & CT’s) and Limit Amps Battery System Battery string, 756 VDC nominal Fused disconnect switch Control and Monitoring Equipment Station control, sequence logic, outer loop controls Operator panel Battery monitor and data acquisition sys tem PSIC (relay panel) with Power Trac Auxiliary Equipment 125 VDC station battery with charger Auxiliary power transformer Fused disconnect switch with PT’s & CT’s Harmonic Filters (oil filled capacitors) Common bus filter to meet IEEE 519 [ 1 ] Fused contactor +. Power Conversion Pair Power Conversion Pas System Rating The Vernon BESS is designed to operate for up to 10 seconds at a maximum plant power demand of 5 MVA immediately after a takeover following a loss of utility grid power. Presently, the plant peak demand is about 3.5 MVA and generally ranges between 2.5 to 3.0 MVA during a 24 hour period. The critical loads make up about 2.1 MVA of the overall plant demand. Nominal ratings for the Vernon BESS are shown in Exhibit 5 below. Upon sensing a loss of utility voltage, the BESS automatically controls the following functions: 1. The incoming circuit breaker is opened. 2. The existing plant control system sheds all but the critical loads (2.1 MVA). 3. The BESS will carry the plant load (up to 2.8 MVA of which 2.1 MVA are critical) for up to one hour, or, until such time that the utility power has been restored. 4. Once the utility feeder voltage is present, the BESS can automatically reconnect (manual reconnect is also available) the isolated plant load with the utility. Exhibit 5. Ratings for Vernon BESS Base voltage at 1.0 pu 4160 Vrms L-L Frequency 60 Hz Continuous power rating 3000 kVA Peak power rating (10 sec.) 5000 kVA Nominal current rating 416 Arms Nominal de voltage rating 756 Vdc Number of series battery strings 2 Nominal battery capacity 5000 Ah @ the 1| hour discharge rate Number of power converter 3 pairs (PCP) PCP power output rating 575 Vac PCP de voltage input range 600 - 900 Vde Lead-Acid Battery System At Vernon, the battery selected and being used is an advanced valve-regulated lead-acid (VRLA) ABSOLYTE® IIP modular battery system manu- factured by GNB Technologies. For more than 100 years, lead-acid batteries have been used for many essential standby and portable power applications. In the past twenty years, ad- vancements in lead-acid technology and battery construction have lead to the production of large industrial-size, sealed, low-maintenance VRLA battery cells like the one being used in the Vernon BESS application. The VRLA battery cell design is completely sealed and employs a pressure relief safety valve. This electrochemical device operates on the basis of oxygen recombination technology, uses starved electrolyte absorbed glass mat construction and has no free acid to spill. The cells store energy effi- ciently, economically and safely, do not require water addition, and during normal charge/dis- charge operation do not give off gasses as a tradi- tional flooded vented lead-acid battery cell can. By using the VRLA battery at Vernon, the required floor space needed to house the two strings of bat- tery cells was reduced by over 50% as compared to using a flooded battery. Since the VRLA cells are sealed, battery cells are arranged three to a module and stacked one-on-top of each other eight modules high. The battery assembly was designed and certified to meet a seismic zone 4 earthquake. Low maintenance is especially important for util- ity companies and industrial users having a BESS. Since the Vernon BESS system is unmanned and operates automatically, servicing the system is keep to a minimum with the VRLA battery sys- tem and operating costs are lower. Battery Layout The battery system, shown in Exhibit 6, consists of two parallel strings, each having 378 GNB model 100A99 2 - volt VRLA ABSOLYTE® IIP modules connected in series providing a nominal 756 volts de. Each 100A99 module contains three model 100A33 cells connected in parallel. A metal housing for the 2 - volt cells is used to Exhibit 6. VRLA Battery Strings assemble a single power module. The tray has three basic parts: a container to house the cells, restraint bars to hold the cells within the container, and a clear plastic protective cover to insulate the cell connectors. The system contains 48 stacks of batteries per string arranged 46 stacks 8 high and two stacks 5 high. The total installed weight of the battery as- sembly is in the area of 612,000 pounds (305 short tons). At the end of each string is a de disconnect switch fused at 4000 amperes. Each of the battery stacks are monitored for voltage, temperature, and potential ground faults. Pilot cells, as well as string current and hydrogen sensors are also monitored. Power Conditioning System (PCS) The PCS part of the BESS consists of a voltage source inverter which is designed to operate as either an inverter when discharging the battery or as a rectifier when charging. The PCS is designed with self-commutating static switches capable of supplying the reactive power needs of the Vernon plant. The ac waveform has some result- ant harmonic content which it filters to meet IEEE 519 standards. The building block of the PCS at Vernon is a 6 - pulse converter arranged in pairs forming a 12 - pulse power converter module (PCP). A simpli- fied circuit diagram of one PCP is shown in Exhibit 7. Each PCP, therefore, forms a 12 - pulse bi-directional voltage source using Gate- Turn-Off (GTO) thyristors in the power conver- sion circuits making up the converter pair. Each GTO is paralleled by a reverse diode to give the converter the capability of handling power flow in both directions. The de link capacitor bank is necessary to absorb ac currents reflected by the converters onto the de bus. Each 6 - pulse converter is connected to a power transformer designed for static converter opera- tion. The connections are arranged to provide an equivalent 12 - pulse wave shape when connected to two 6 - pulse converters operated with firing signals 30 electrical degrees apart. To assemble the overall power conditioning sys- tem, three of the PCPs are connected in parallel to achieve the power rating requirements for the Vernon BESS application. Each PCP is connected to the power system through an ac contactor. Exhibit 7. Pulse Power Converter Pair Outline The PCP converter hardware line-up is shown in Exhibit 8. There are four main cabinets. The two 30" wide cabinets on the right contain the 6 pulse GTO converters. A 24" cabinet in the center con- tains the de link capacitor bank and protection. The application specific de line panel, 60" cabinet on the left, contains the de link converter, capacitor charging circuit, I/O interface, control isolation transformers, contactors, and miscellaneous hard- ware. Theory of Operation For most operating conditions, the BESS is equiva- lent to a voltage source behind the transformer reactance (X,) as shown in Exhibit 9. The PCS generated voltage (V,,) is completely controllable within the current rating of the converter equip- ment. Consequently, the ac current can be supplied at any phase-angle relative to the terminal voltage (V,). This feature permits the BESS to generate real and reactive power in all four quadrants as indicated by the capability curve. The BESS power generating capability is limited by the thermal rat- ing of the converters and the available battery volt- age. Overload capability will permit operation at higher currents for limited periods of time, as sug- gested by the dotted capability curve. Reactive Power (kVAr) Capacitive Overload ae Capacity ve Power (kW) Rated Converter Capacity Charging Discharging Equivalent Circuit V5 Xx, V, O AN Distribution — Network I - Phasor Diagram i Exhibit 9. Active and Reactive Power Capability Exhibit 8. PCS Converter Harware Line Up BESS Control System A simplified block diagram of the control system is shown in Exhibit 10. Terminal voltage magni- tude and power control loops are included with the PCS. Power and voltage orders are provided by the Station Control. Station Control Control of the PCS to meet the various modes of operation is provided by the station level control as shown in Exhibit 10. The control consists of a microprocessor controller for regulator functions and a PLC for sequencing and protection. When operating on utility, the voltage order is de- rived from a closed loop VAr regulator which maintains the PCS at a desired power factor. The power order follows the charging needs of the bat- tery or the operator can schedule the system to automatically reduce the plant demand charges. When isolated from the power grid, the voltage order is adjusted to maintain nominal plant voltage (4160V) and the power order is dynami- cally adjusted to hold frequency (60 Hz). When resynchronizing, voltage is adjusted to match measured utility voltage and plant 1 of oR Ofe Se frequency is adjusted to match measured utility frequency and phase-angle. Synchronizing with the utility is supervised by a standard synchro- nism check relay. Battery Monitor Control The battery monitoring control performs five ma- jor functions: Calculates the state-of-charge of the battery. 2. Provides for battery charging and discharging control. 3. Monitors the health and status of the battery. 4. Records battery operation for future optimi- zation and warranty management. 5. Detects ground faults, should one occur. The battery monitoring function is implemented in a PLC working with the Operator Interface Computer. The computer consists of an industry standard PC running a graphical interface program for data storage and display. Relay Panel Control The relay panel consists of standard utility grade protective relays designed to monitor the point of utility connection. The control logic will trip the main plant breaker if the utility feeder is faulty. The relays monitor and detect the following conditions. * faulted phase detection * over / under frequency * 1-phase power interruption + 3-phase power interruption While the plant is isolated, the relay panel will detect when three-phase utility feeder voltage is restored. If the operator then requests a resynchronization, the relay panel will super- vise the breaker closing using a synchronism check relay. All relays are self resetting to al- low for unattended automatic operation. Final Commissioning Test Results Acceptance tests of the Vernon BESS instal- lation were completed on November 5, 1995. Testing actually started in late September on the various pieces of hardware. A brief over- view of the results follows. Exhibit 10. BESS Control System VRLA Battery Strings Battery capacity developed to 100% on the third 80% depth of discharge cycle. This was accomplished by running the BESS as a peak shaving device taking 500 kW per hour off the peak demand of the plant over an 8 - hour discharge period (4,000 kWh). The system was cycled at increased loading (up to2 MW) for short periods of time (10 minutes, then 20 minutes) and then allowed to recharge. BESS Plant Takeover ( UPS Protection) The Power Conditioning System consists of three PCP converter pairs connected in parallel. This hardware performed extremely well under several different power output operations. Fol- lowing the battery cycling tests, the battery en- ergy storage system was ramped up in blocks of 500 kW to within a few hundred kW of the total plant demand. At that time, the plant require- ments were running around 2,900 kW. The BESS was supplying 2,500 kW and the utility was supplying the other 400 kW. When the power output of the BESS was increased to a point that it reached or exceeded 100% of the plant load, the plant substation main breaker opened and isolated the BESS from the utility feeder. The system was allowed to operate for 15 minutes carrying the entire plant load before transitioning back to the utility grid following a synchronism check. By design, the system will not allow power to back-feed into the utility grid. Having proven the system was fully capable of carrying the entire plant load and the system worked according to plan, the next critical test was to simulate a power failure and allow the BESS to instantaneously pick up the entire plant load from a standby condition. The critical loads spread throughout the plant con- sist of about 25 induction motors plus lighting and controls. Four of the motors, totaling 1600 hp, are connected at the 4160V bus. The balance of the motors, about 1400 hp, are connected at 480 Vac. Just prior to running the test, the battery strings were charging at a low rate corresponding to about 480 kW. While charging, the BESS is also com- pensating the reactive component of the plant load to maintain unity power factor at the point of util- ity connection. This is done to maximize the power available for charging the battery. The total reac- tive compensation while charging, including the filter component, is about 2200 kVAr. The total plant load when the test was conducted was about 3000 kW (excluding the BESS charging kW) and includes about 2100 kW of critical loads. To simulate a power interruption, the plant breaker was manually tripped. The critical plant loads im- mediately transition to the BESS following the manual breaker trip. To support these loads the battery string current increased to about 1300 am- peres and the battery voltage dropped slightly. Since the BESS regulators maintain the proper voltage magnitude and frequency, the power output naturally follows the needs of the plant loads. From the plant perspective, the breaker trip test was essentially bumpless. All critical loads including sensitive electronic equipment such as PCs were unaffected by the transition. 10 Motor Starting While the plant was isolated from the utility feeder, a 100 hp motor was started. The test proceeded without difficulty. Resynchronizing Once utility feeder voltage is present, the BESS may be requested to reconnect the isolated plant load with the utility. Resynchronizing requires that the instantaneous voltage across the open plant breaker be reduced to zero. To accomplish this, the isolated plant voltage magnitude, frequency and phase-angle are adjusted to match the utility. The breaker is closed if the voltage is within +/- 10% and +/- 6° for a two second period. When this test was run, the isolated plant load was about 2300 kW (the plant loading was increased slightly during the test). The battery voltage fol- lowing 30 minutes of operation was about 740V and the string current was about 1550 amperes. Immediately following the breaker closing, the BESS output power is reduced to smoothly tran- sition the plant load back to the utility feeder. Readouts from oscillograms which show the response of the system during the breaker trip test, response of BESS and plant during motor starting and resynchronizing, BESS voltage waveform and harmonic content measured during isolated operation, will be displayed and discussed during the presentation of this paper. ACKNOWLEDGMENTS The author wishes to recognize the following individuals whose contributions to this project were essential. General Electric: W. Hill, C. Harbourt and D. Wanner (converter design), C. Wegner and M. Cardinal (system software), Dick Parker, site construction manager and Ron Bitner who acted as project manager. GNB Technologies: M. Jesko (battery system layout and charging ). The author wishes to further recognize the following individuals who contributed greatly to the Vernon BESS Project and to the content of this paper. General Electric: N. W. Miller , R. S. Zrebiec, and R. W. Delmerico, Power Systems Engineering Department, Schenectady, NY. GNB Technologies: The author is also grate- ful to J. Szymborski for his contribution and assistance in editing this paper . Also, to Jim Ippolito for helping to organize the graphics. Sandia National Laboratories: Thanks to Rudy Jungst for his help in editing this paper. To Sandia Labs for its support and contributions through cost-share contracts in the develop- ment of the ABSOLYTE® IIP VRLA prod- uct. Also, for its continued interest in the mar- ket development of battery energy storage technology. Upon final commissioning of the BESS at Vernon, Sandia has contracted with GNB to provide performance and economic benefits data during the operation of the sys- tem over the next four years. 11 REFERENCES “Design and Commissioning of a 5 MVA, 2.5 MWh Battery Energy Storage System”. N. W. Miller, R. S. Zrebiec, R. W. Delmerico, G. Hunt: IEEE T&D Show, Los Angeles, CA, Sept. 1996 “Battery Energy Storage Systeins for Electrical Utility, Industrial and Commercial Applications. An Opportunities Analysis”. G. W. Hunt: IEEE of Central America CONCAPAN ’95, Guatemala. Nov. 1995 “Ten (10) MW GTO Converter for Battery Peaking Service”, L. H. Walker: IEEE Trans. Ind. Appl., Jan/Feb. 1990, Vol. 26 #1, pp. 63-72. Battery Energy Storage Systems for Electrical Utility, Industrial and Commercial Applications. An Opportunities Analysis IEEE Convention for Central America, CONCAPAN ’ 95 - Guatemala George W. Hunt GNB Technologies Industrial Battery Company 829 Parkview Blvd. Lombard, Illinois 60148 ABSTRACT Battery Energy Storage is a technology that can play a flexible , multi-functional role in a wide range of electric utility systems and industrial applications. Battery Energy Storage Systems (BESS) have the potential to offer electrical utilities an effective tool in meeting their energy management and power regulation needs by managing their resources to cope with their changing environment. This paper describes the conceptual design of a Battery Energy Storage System (BESS) for electrical utility, industrial and commercial applications. The paper further describes the various types of applications, combination of applications and potential benefits that a BESS can provide. BESS can be an economic and environmentally friendly resource for electrical utilities and industrial manufacturers. A system can operate on the supply side of the meter and be owned by the utility, or, be installed on the demand side of the meter and owned by the customer. A system could also be beneficial to both parties and jointly owned or leased by one from a third party. The electrical utility industry is changing and its customers are demanding better services at lower costs. Deregulation, increasing competition, more stringent environmental constraints, growing customer expectations for dependable power and the need for more power have all contributed to this movement. BESS can provide the user with a dependable, efficient and controllable source of real and reactive power which is available instantly to support a wide range of generating and distribution applications of energy management and power regulation. Furthermore, BESS can provide an industrial manufacture with emergency backup support for manufacturing processes having critical loads demanding uninteruptible power, even if there is a lost of the ac utility connection. BESS_ has the potential to provide other substantial benefits in terms of better asset utilization by utilities and providing demand side energy management functions such as demand peak reduction and peak shaving which can lower electrical costs for a large customer. With a battery energy storage system, an electrical utility company has the potential to defer or eliminate new transmission or distribution feeder lines, defer substation upgrades, store off-peak power and use it for spinning reserve or peak shaving when needed and perform power regulation functions. Battery energy storage is a technology that can also play a role in the industrial marketplace to assist customers in effectively managing consumption of electric power and by providing high-value in power quality and reliability applications. The potential economic benefits can be high. This paper addresses how battery storage can alleviate future electrical utility capacity constraints and how a BESS can provide customers with a cost effective tool for energy management and help solve reliability problems. BACKGROUND Traditionally, battery energy storage has been promoted as mainly a load-leveling option for utilities. This traditional perception is giving way to a new perspective that identifies battery energy storage with multiple applications and benefits in three categories: 1) Generating, 2) Transmission and Distribution, and 3) Customer-Side of the Meter. Applications within these categories are very different from the classic load-leveling application originally promoted for battery energy storage. range of electrical utility, industrial and commercial applications. One such alliance is GNB Technologies and The General Electric Company. The Battery Energy Storage System Program at GNB Technologies has been to develop integrated, structured battery systems for high value-added applications in the utility sector and for applications on the customer-side of the meter. This program has been in existence for the past three years and includes a strategic alliance with The General Electric Company. GNB has worked closely with the GE Power Systems Engineering Department, Installation and Service Engineering group, and Drive Systems Department. The objective of the alliance has been for both parties to work together in developing fully integrated battery energy storage systems and establish a joint selling strategy for the complete supply, installation and service of BESS to the electrical utility and industrial marketplace world wide. The team of GNB and GE have just completed the construction of a 5 MVA / 3.5 MWh battery energy storage system in California for an industrial application where critical loads for the environmental air quality controls at a lead recycling center requires an uninterrupted supply of power. The system also provides for peak shaving and VAr compensation. The system goes on line in December, 1995. The primary objective of this paper is to characterize these new applications and develop quantitative estimates of application requirements and potential benefits. By identifying and characterizing the high value utility and customer side applications for BESS, the GNB/GE team can best target its development and sales activities to these specific applications, markets, and potential customers. This task is not easy to undertake. The applications, as you will see in the sections which follow, are very site-specific and benefits depend to a great extent on the nature of a specific utility system, load requirements and rate structure imposed by the utility. Industries with high-tech manufacturing processes where small fluctuations in power can cause large losses in the product being manufactured, data being collected or transmitted or can cause environmental damage can be extremely costly and time consuming to correct. These outages are extremely hard to quantify as to the potential economic benefits derived from having a BESS which can prevent this from happening. One type of manufacturing that comes to mind is the semiconductor industry which produces integrated circuits. The banking and health care industries are other commercial businesses requiring reliable power. The lose of AC power can be costly and very disruptive. Installing a BESS can be one possible solution which can help to prevent shutting down production lines or emitting toxic waste into the air. INTRODUCTION The storage of electric power and energy during hours of low energy use, at night for example, for release during the day when demand is high is a good application for battery energy storage and can provide significant benefits. Besides battery energy storage, there are other storage devices being used for storing energy for this purpose which I will address shortly. Electric utility companies typically meet the fluctuating demands for power with a combination of generating plants with different economic and operating characteristics. Generally, the portion of the load that remains constant is supplied by large coal, nuclear, or hydro electric power generating plants. These types of plants typically carry the electrical base load and can be very efficient and use low cost fuels. The portion of the demand curve for the utility that fluctuates, however, is usually met by a combination of intermediate and peaking plants These plants are generally older units that burn fossil fuels such as oil, gas or coal and are less efficient. When we store energy that was generated form lower cost fuels such as water, coal or nuclear plants during the evening hours (off-peak when utilities typically have low demand and offer lower pricing per kW/kWh) and release it to satisfy a portion of the peak demand during the day, we can displace the higher cost of fossil fuels burned when utilities bring on smaller peaking units during peak demand periods. A utility company peak demands are typically in the morning and afternoon hours and can vary between summer and winter months. At present, the only form of energy storage used by the electrical utility industry is pumped-hydroelectric power. This form of energy storage can be limited by the availability of water, topography of the land, and environmental concerns since the typical system requires vast amounts of acreage for building a reservoir and dam. The reservoir becomes the storage device. Other forms of energy storage include compressed air, hydrogen storage, Superconductive magnets and flywheels. Most of these technologies are extremely expensive to construct, cost a lot to operate and maintain, require several years to plan and construct, are very site specific and can be damaging to the surrounding environment. As for battery energy storage, a large 20 MW / 40 MWh BESS facility for example requires less than a acre of land, can be located just about anywhere, since it is clean and environmentally friendly, and can be constructed quickly and easily in less than a year. continuous power rating for a single PCS module may be 1,000 kVA or kW. By connecting modules in pairs or parallel, one can increase the power rating to 2,000 kVA or 3,000 kVA or higher ratings if required. Battery systems, like the GNB ABSOLYTE®IIP valve regulated lead-acid modules, are offered in a wide range of capacity sizes which can easily be assembled into standardized horizontal stacks and connected in series and or parallel configurations providing 1,2,3, or up to several hours of stored energy at rated power. Control System To enable a simple interface with other equipment on the distribution system, the BESS control system will be designed to emulate a rotating synchronous machine attached to a large inertia and prime mover. For instance, when connected to a power grid (normal mode) terminal voltage is maintained according to the local area needs established by the control system, and frequency/phase of the BESS voltage is adjusted to maintain a scheduled power flow on the ac interconnection. When separated from the grid or during a black-start (isolated mode) the PCS will establish the frequency and phase or voltage. For either case, the behavior can be made superior to a rotating synchronous machine since the inertia, governor droop, and damping can be set (and dynamically adjusted, if necessary) to suit the needs of the overall power system or load. Another key advantage is that the BESS “prime mover” can both supply and absorb energy within the capacity of the battery system. APPLICATIONS PERSPECTIVES The various types of applications that Battery Energy Storage Systems can be classified into represents three major groups, namely; 1) Generating-Related Applications, 2) Transmission and Distribution Applications, and 3) Customer-Side of the Meter Applications. A general description covering each of the primary applications within each group are shown below. 1. Generating-Related Applications Capacity Deferral: As demand for electrical energy grows and the load grow projections by utility planners shows continued growth , a battery energy storage system can allow a utility to possibly defer the construction of new generating plant for several years. If the load growth projections are not realized, the utility may not be required to invest in new generating equipment or facilities. The Savings in capital associated with paying for a new generating plant, which the utility may not need, versus the installation of a BESS to handle the short term growth in demand can be substantial. The utility rate paying customers typically pay for new generating plants through higher rates over the long term. Investing in a BESS can be a lot less expensive than building a new generating plant. BESS can allow the utility to defer the decision to build one and defer the capital spending for a number of years. Currently, pumped hydro-electric power plants are the most commonly used energy storage system for utilities. Another is compressed-air storage. However, both these technologies have not gained widespread acceptance as a commercial technology available today, very much like Superconductive magnets which are years off in all practicality. A pumped hydro-electric storage facility is mainly used for spinning reserve requirements and is generally suitable for large central storage. On the other hand, small to medium modular battery energy storage systems, such as teh designs available from GNB and General Electric, can be distributed throughout a utility to capture additional benefits while also allowing the utility to claim generation capacity deferral credits when new generating plants are not constructed. Spinning Reserve: Electric utilities in the United States are typically required to maintain a percentage of reserve capacity as standby power in the form of “spinning-reserve™ for handling unplanned load demands which can cause power outages if not handled properly and quickly. This reserve power and energy, available for immediate dispatch, is an operating cost for a utility and can range from three to as much as seven percent of its generating costs. For an interconnected utility network such as we have in the US, the extent of spinning-reserve requirements is established through negotiations within the utility power pools with inputs from the Public Utility Commission reliability councils. In places like Alaska, Hawaii and Puerto Rico, the local utilities are cut off from having a grid network consisting of several utilities on the same network and must provide for its own form of spinning-reserve capacity to handle unplanned increases in load demand. In a lot of cases, the utility may never use its spinning reserve but, has to pick up the expenses to keep the system operating and available at all times. An example of how a utility will account for spinning- reserve may go something like this. Lets say a utility operates a thermal generating plant that is rated at 500 MW but only operates it at 450 MW. The utility may count the remaining 50 MW as spinning-reserve. This is in contrast to a view by many, outside the utility industry, that combustion turbines are installed specifically for spinning- reserve purposes. Battery energy storage systems may allow a utility to operate the thermal plant mentioned here at full new lines are installed or upgraded to handle the increase in power and energy demands in areas experiencing rapid or sustained growth. Transmission lines can cost up to one million dollars per mile to install and can take up to ten years to get all of the necessary work completed. In the mean time, a BESS offers the utility the alternative option of installing a battery energy storage system as a resource first. This can be a cost effective approach in deferring the construction of an expensive and time consuming job of building a new transmission line to accommodate increasing or “projected” demands for power and energy. Distribution Facility Deferral: This application is similar in concept to the transmission facility deferral. A utility may have the ability to postpone installation of new distribution feeder line and/or upgrading transformers at sub-stations by supplementing the existing facilities and lines with a BESS. In a lot of cases, the anticipated growth that a utility expects may never materialize making the BESS a wise decision. Not only can the utility defer the capital investment, but, a BESS can provide the utility with local demand peak shaving and serve to improve power reliability and quality to its major industrial customers at the same time (multi-functional applications can be very beneficial). Transmission Line Stability: A typical electrical utility has a lot of components attached to its transmission lines. It is highly important that a utility maintain the synchronization between generating equipment, _ its transmission network, and distribution feeders. Voltage swings can occur at any time as loads vary placing a sudden demand for power on the network. For this reason, a utility may only load a transmission line at 80% of the lines capacity allowing for sudden increases. Damping of first swings in transmission lines can be accomplished with relatively a small to medium size BESS. This is a particularly significant problem in long transmission lines experiencing voltage swings generated form industrial machinery which demand lots of power instantly. When you couple this problem with peak demand periods, a utility must be careful as to transmission line loading. In areas like Australia, some utility companies have long skinny transmission lines into areas experiencing rapid growth and this can be a big problem. Alleviating this problem with a BESS can allow a utility to reduce the transmission lines’ need to accommodate swings and allow the utility to import larger amounts of power over the same line. A two or three percentage additional increase in loading can be significant. Voltage Regulation: Voltage regulation is a relatively minor application for BESS. Utilities use capacitors to keep voltage at the load-end of distribution systems within a few percentage points of voltage at the generation-end of the line. A typical utility policy might include 0.6 MVAr of capacitors for every MW of load. A BESS with self commutated inverters (PCS) can achieve the same voltage regulation and displace capacitors. This is one type of application where a BESS to be cost effective must be used for multi-applications and therefore provide multi-benefits. Demand Peak Reduction: Reduction of peak demands by heavy industrial customers by using battery energy storage system can benefit a utility by reducing the need for additional investments to upgrade transmission and distribution feeder lines and sub-stations serving a general industrial park area. A utility-side of the meter BESS located at or near a customer site can provide for this benefit. Also, the BESS can be used to improve power quality /power reliability at the customer and be used for other applications as described in the previous sections Light commuter rail service is a good example having two very distinct demand peaks. One in the early morning when commuters are going to work and one in the late afternoon when they are returning home. A BESS could provide the utility or customer with demand peak reduction during periods when the utilities production costs are typically at their highest. Utilities may wish to consider demand peak reduction as a Generating related type of application also. 3. Customer-Side of the Meter Applications Demand Peak Reduction: Reduction of peak demands by heavy industrial manufacturing customers by using a BESS can benefit a customer by reducing its electric bill. This is particularly important now when a lot of US electrical utility companies are going to a time-of-day rate structure. By storing energy during off-peak hours at low rates per kWh, then, discharging this energy during peak demand periods, the customer may significantly reduce its monthly charge associated with the demand portion of its bill. There is also the benefit of using lower cost energy purchased at night when rates are generally lower and then using this energy during the day when rates area typically higher during peak hours. The higher and shorter the duration of the peak demand, the greater the amount of benefits in cost savings that can be obtained. At the same time, a BESS can also provide additional benefits in the form of improved power quality and provide plant wide UPS protection to critical loads needing uninteruptable power. Peak Shaving: This application is similar in concept to load-leveling and peak demand reduction. Peak shaving is associated with the amount of energy a customer uses (kWh), where as, demand peak reduction is associated with the amount of power (kW) that is required to handle the TABLE I CUSTOMER-SIDE OF THE METER APPLICATIONS AND REQUIREMENTS Battery Duty Cycle | Expected minshrs | Capacity | Per Battery Life | Customer Reliability & Power Quality (UPS) POTENTIAL BESS BENEFITS This section of the paper presents an assessment on the summary of the potential benefits for a electrical utility company and for applications on the customer-side of the meter that can be attributed to the ownership of a battery energy storage system. An attempt has been made to assess and determine which potential benefits appear significant. There can be a potential value of quantified battery storage benefits and a potential value that can not be easily quantified. Both types of benefits are shown in Table IV. There should be a note of caution, however. Not all of these benefits are applicable to utilities worldwide. Different countries and governments regulate the electrical utility industry differently and have major differences in environmental regulations. A lot of what has been is changing and will continue to change as technologies improve and global economies grow. Electrical Utility Benefits: The overall value (benefits) to the electrical power utility industry for incorporating battery energy storage systems in their overall resources can be related to three major areas, generating power, transmitting and distributing power and the environment. Since not all utilities are the same (type of power generating equipment, efficiency, area served, quantity and types of customers, load growth projections, financial stability) not all the potential benefits listed in Table IV may apply or be obtained simultaneously. TABLE IV TYPES OF POTENTIAL BESS UTILITY BENEFITS ¢Spinning-Reserve *Area Frequency Regulation «Transmission Line Deferral *Reduction in Transmission Losses System Voltage Stability *System Voltage Regulation *First-Swing Stability for handling Faults *Auxiliary Power (Black-Start) «Improve System Modeling & *System Damping *Transformer Deferral *Generation Deferral Strategic Benefits *Reduce Air Emissions Operating Flexibility eImprove Urban Air Quality *Improve Transmission & Distribution Reliability «Dispatch Constraint Power Transfer Limits Relief *Generating System Reliability +Lessen Electromagnetic Fields *Power Generation Production Cost Savings The most significant benefits shown above in Table IV for a utility appear to be spinning-reserve, area frequency regulation, transmission and distribution deferrals, and those benefits dealing with environmental issues. The quantified total value for BESS can be a combination of several benefits. BESS may not be fully justifiable or have an acceptable payback period when considering only one type of application. A battery energy storage system is flexible in that it can provide a utility with multiple benefits when designed and deployed properly. Some of those benefits identified may not be immediately realized and not begin until several years out. BESS is a relatively new resource and technology for the utility industry and utility planners to consider. This is also true for industrial manufacturing companies which typically install low voltage UPS equipment to provide backup power and power quality to their production lines. This may change when large companies investigate the full benefits associated with BESS. Understanding its near term benefits and future benefits generally requires and results in a today. It offers utilities a low risk technology in energy storage and a system that can be designed & build in a very short time. As utilities and utility planners become more educated as to how BESS can be applied to their system, and the benefits that a system can provide, small to large systems will start to appear on both sides of the utility meter in the near term. For further information regarding BESS and its potential applications , contact George W. Hunt, GNB Technologies, 829 Parkview Blvd., Lombard, Illinois 60148 Phone (708) 691-7813 fax (708) 691-7827 ACKNOWLEDGMENTS The author gratefully acknowledges the assistance of The General Electric Company with the BESS design and description section of this paper. Thanks are extended to Robert W. Delmerico, Nicholas W. Miller and Robert S. Zrebiec, GE Power Systems Engineering, Schenectady, New York , USA. REFERENCES 1. Battery Energy Storage for Utilities, A New Pespective, SAND91-0450/2525/700 tN Utility Battery Storage Systems Program Plan, FY 1994 -FY 1998, US Department of Energy, DOE/CH10093- 258, DE94000239, February 1994 3. Battery Energy Storage for Utility Applications: Phase I, Opportunity Analysis, SAND94 - 2605 * UC - 212, Reprinted March 1995 4. Report - Battery Requirements and Applications, for Low-Maintenance_Lead-Acid_ Battery Storage, US Department of Energy, Electric Power Research Institute 11 e|nje Bee Seite my Energy Storage System Power Management Solutions, the GNB Advantage GNB TECHNOLOGIES is a global provider of quality integrated power techno- logy products, power management and environmental services. GNB serves cus- tomers in the industrial power control, electric utility, telecommunications, mili- tary, automotive, electric vehicle and environmental markets in more than 50 countries. Owned by Pacific Dunlop, Melbourne, Australia, GNB’s world head- quarters is in Atlanta, Georgia, USA. The company has operations in Australia, Canada, Europe, Great Britain, Japan, New Zealand, Southeast Asia, the United Arab Emirates and the United States. GNB is an energy systems company marketing complete turnkey Battery Energy Storage Systems (BESS) to industrial, commercial and electric utility customers. The company combines its commercially proven, patented ABSOLYTE® IIP storage battery technology with the products, knowledge and quality of General Electric Company. BESS Applications Battery Systems in Electric Utility Applications Battery Energy Storage is an option that can help electric utilities address the new strategic factors of deregulation and privatization by improving cost-effectiveness, reliability and power quality and by reducing the environmental impact of electricity generation and distribution. BES Systems function over a wide range of conditions, permitting flexible utility dispatch of energy. As a generation resource, a BESS can store off-peak energy and provide power when it is needed. As a distribution resource, a BESS can defer or possibly eliminate the need for new transmission or distribution lines, resulting in cost savings and greater asset utilization. The incorpo- ration of battery storage with renewable energy generators will provide greater utility grid stability, thus allowing increased use of these resources. Generation of Power & Energy ¢ Spinning Reserve * Renewable Generation Support ¢ Generation Capacity Deferral ¢ Load Leveling ¢ Area/Frequency Control ¢ Improve Reliability Transmission & Distribution ¢ Transmission Line Stability. ¢ Transmission Facility Deferral ¢ Voltage Regulation ¢ Distribution Facility Deferral Customer Service ¢ Customer Demand Peak Shaving »* Power Quality, Reliability, UPS ¢ Transit System Peak Reduction Battery Systems in Industrial and Commercial Applications Battery Energy Storage is a controllable demand-side management option that can provide industrial manufacturing companies and commercial customers improved power quality, uninterruptible power, and energy-management capability. This capability provides for power demand reduction and peak- shaving by storing lower cost energy at night and using it during peak hours of the day when energy costs typically are much higher. Power Control, Reliability & Energy Management * Critical Process Protection (UPS) * Power Quality Improvement * Peak Demand Reduction * Peak Shaving (Load Leveling) * Power Factor Correction The combined strength of GNB and GE assures customers of having a highly qualified turnkey supplier of a fully engineered, designed system, technically integrated with quality components, and serviced by the world leader of battery energy storage tech- nologies and systems. GNB and GE have developed and are offering power management solutions today. GNB and GE are committed to delivering a quality product, services, and customer satisfaction on a global basis. Together, GNB and GE offer worldwide sales, services and support of BESS. Engineered systems are fully warranted and backed by years of experience within both major companies. With the GNB/GE Advantage, you will have full access to pre- system installation analysis, turnkey installations, site manage- ment, and product education and training. Renewable Energy Power Generation Transmission/Distribution Battery energy storage systems can be designed to perform multiple utility applications in generation, transmission and distribution, and customer service. Critical Process Backup Quality & Reliability Assurance Environmental Control Protection Segregation of the applications into groups is an organizational tool. It does not represent a segregation of BESS functions. A BESS is most valuable to a user when it performs “multiple functions” in more than one of the groups of applications shown above. GLOBAL OPERATIONS NORTH AMERICA GNB Technologies 829 Parkview Boulevard Lombard, Illinois 60148-3249 U.S.A Tel: 1.630.629.5200 Fax: 1.630.629.2635 GNB Technologies 4500 Dixie Road, Unit 9B Mississauga, Ontario L4W1V7 Canada Tel: 1.905.624.1107 Fax: 1.905.624.1801 EUROPE GNB Technologies Farndon Road, Market Harborough Leicestershire, LE16 9NP England, United Kingdom Tel: 44.858.434409 Fax: 44.858.434431 GNB Technologies Ansell Edmont Europe, N.V. GNB Division Wijngaardveld 34C B-9300 Aa Ist Belgium Tel. 32.53.710505 Fax: 32.53.710181 MIDDLE EAST/AFRICA GNB Technologies P.O. Box 44026 Abu Dhabi, United Arab Emirates Tel: 971.2.344561 Fax: 971.2.348644 PACIFIC NORTH GNB Technologies Japan Towa-Hatano Building, 6F 4-4, Hongo 2-Chrome, Bunkyo-ku Tokyo, 113 Japan Tel: 81.3.5689.6390 Fax: 81.3.5689.6393 PACIFIC SOUTH GNB Technologies 55 Bryant Street Padstow, N.S.W. 2211 Australia Tel: 61.2.772.5700 Fax: 61.2.774.2966 GNB Technologies Hutt Park Road Lower Hutt P.O. Box 360926 Moera Lower Hutt New Zealand Tel: 64.45.684.269 Fax: 64.45.686.687 GNB Technologies 111 Kallang Way 2 Singapore 1334 Tel: 65.745.0388 Fax: 65.745.0688 CHINA GNB Technologies 16/F Tower 1, The Gateway 25-27 Canton Road Kowloon, Hong Kong Tel: 852.2.956.6688 Fax: 852.2.956.2161 LATIN AMERICA GNB Technologies 375 Northridge Road Atlanta, Georgia 30350 Tel: = 1.770.551.9136 Fax: 1.770.551.9149 TECHNOLOGI TORUS. ain Cur ae ac EM A Pacific Dunlop Company 3 S Why GNB BESS? Because GNB offers highly reliable, fully integrated, turnkey Battery Energy Storage Systems to electric utility, industrial and commercial customers using proven technologies and components that are available now... a GNB BESS can provide the user with storage of electricity during off-peak hours when energy costs are low and deliver it on demand during on-peak hours when energy costs are high... and, because a system can also provide uninterrupted power to critical loads preventing troublesome and costly outages... and, because the system can be designed for a particular application, constructed, and commissioned normally in a matter of months. With GNB BESS you can: locate where needed install quickly size system to application defer substation upgrades provide spinning reserve improve customer service provide dispatchable power protect critical loads provide demand-side energy management lower power demand charges improve power quality and reliability provide frequency regulation provide power factor correction save on energy charges eeceeeee ec ece eee Specifications Systems can be tailored to meet the specific power and energy needs of an application requiring several hundred kW or up to fifty MW or higher if needed. Output voltage can be low, intermediate, or high with 50 or 60 Hz capability. Energy storage can be provided in minutes or up to several hours at maximum capacity with multiple paralleled systems. BESS ABSOLYTE® IIP Battery Power GNB revolutionized the battery industry in 1983 with the introduction of its first industrial valve regulated lead acid (VRLA)battery, the ABSOLYTEI. GNB has continually improved the Absolyte product design and manufacturing processes ever since. In 1993, GNB intro- duced ABSOLYTE IIP, featuring an AVERAGE 15% increase in capacity over ABSOLYTE II, introduced in 1986, without an increase in the size of the container. ABSOLYTE IIP ensures Superior Performance, Reliable Power, Space Efficiency and Simplified Installation, Reduced Maintenance and a High Degree of Safety. Patented hybrid grid alloy gives the ABSOLYTE IIP battery a long service life in float service, deep cycle capability with deep discharge recovery. Battery cells are sealed, never require watering, are virtually spill-proof, leak- proof and explosion resistant. Batteries are stackable, having modular steel trays which allows for maximum power density, quick on-site installation, and standard units meet UBC seismic zone 4 require- ments. ABSOLYTE® IIP technology and con- struction is field tested and proven, offers maximum flexibility for a wide variety of BESS applications Battery Energy Storage System 4.2 Auxillary Power seeeeee The basic concept is to store electrical energy for dispatch at a time when its use is more economical, strategic or efficient. The BESS accepts electricity from a utility grid, stores it in batteries, and returns it to the grid or supplies it to the customer demand. To perform these functions, the Power Conversion System, Battery System and Control and Monitoring equipment must all work together. Utility Grid Protected Loads