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HomeMy WebLinkAboutAppendix E - Feasibility Report - March 28, 2009 “Celebrate the power of nature”TM … with YourCleanEnergy LLC 308 G Street #212, Anchorage AK 99501 907-274-2007 www.yourcleanenergy.us ECONOMIC EVALUATION OF SEA WATER HEAT PUMPS TO PROVIDE SUPPLEMENTAL HEAT FOR MAKE UP AIR UNITS AHU-5 & AHU-6 AND OUTDOOR PAVEMENT HEATING FOR ALASKA SEALIFE CENTER 301 RAILWAY AVENUE SEWARD, ALASKA 99664 USA FINAL REPORT COMPLETED MARCH 28, 2009 BY: ANDY BAKER, PE & LEE BOLLING “Celebrate the power of nature”TM …with YourCleanEnergy LLC TABLE OF CONTENTS EXECUTIVE SUMMARY – HEAT PUMP ALTERNATIVES TO SUPPLY AHU-5 & PAVEMENT HEAT ............................. 3 SCOPE OF SEA WATER HEAT PUMP EVALUATION FOR ALASKA SEA LIFE CENTER ............................................... 4 INTRODUCTION ........................................................................................................................................................................ 5 SUMMARY OF ASLC HEAT PRODUCTION AND DESIG N DEMANDS (NAMEPLATE CAPACITY)................................. 6 CONCEPT GUIDELINES FOR SUPPLYING AHU-5 AND AHU-6 WITH SEAWATER HEAT .............................................. 7 EXISTING ELECTRICAL COSTS FOR ASLC IN SEWAR D, ALASKA ................................................................................. 8 HEATING OIL USAGE BY ASLC ........................................................................................................................................... 10 RECENT AND PROJECTED HEATING OIL COSTS FOR ASLC ........................................................................................ 11 RECOMMENDATIONS FOR INCREASING ENERGY EFFICIENCY OF ASLC FACILITY ................................................ 12 MONTHLY SEA WATER TEMPERATURES AND HEAT ENERGY AVAILABLE .............................................................. 13 EXISTING AIR HANDLER S AHU-5 AND AHU-5 IN ROOF LEVEL FAN ROOMS ............................................................. 14 HEAT PUMP OPERATION AND COEFFICIENT OF PERFORMANCE ............................................................................... 16 SELECTION OF HEAT PUMP EQUIPMENT SUITABLE TO SUPPLY AHU-5 & 6, PAVEMENT HEAT ........................... 17 RESULTS OF SIMULATION WITH ASLC SEAWATER TEMPS AND TRANE RTWD HEAT PUMPS ............................. 18 SCHEMATIC OF EXISTING CHILLED WATER SUPPLY TO AHU-5 + AHU-6 .................................................................. 19 SCHEMATIC OF ALTERNATIVE A: ONE HEAT PUMP IN ROOF FAN ROOM #1 TO SUPPLY AHU-5 ........................ 20 SCHEMATIC OF ALTERNATIVE B: ONE HEAT PUMP IN BASEMENT RM 19 FOR PAVEMENT HEAT...................... 22 SCHEMATIC OF ALTERNATIVE C: TWO HEAT PUMPS IN ROOM 19 OF BASEMENT FOR AHU-5 + PAVEMENT HEATING .................................................................................................................................................................................. 24 MANAGING FREEZE PROTECTION OF HEAT TRANS FER LOOPS IN DUCT COILS .................................................... 26 SITE PHOTOS WITH NOTES – EXISTING CHILLED WATER HX AND PUMP SYSTEM IN BASEMENT ....................... 27 SITE PHOTOS WITH NOTES – EXISTING CHILLED WATER HX AND PUMP SYSTEM IN BASEMENT ....................... 28 SITE PHOTOS WITH NOTES – AHU-5 IN FAN ROOM NO. 1 (NORTH) ............................................................................. 29 SITE PHOTOS WITH NOTES – AHU-5 IN FAN ROOM NO. 1 (NORTH) ............................................................................. 30 SITE PHOTOS WITH NOTES – AHU-6 IN FAN ROOM NO. 2 (SOUTH) ............................................................................. 31 SITE PHOTOS WITH NOTES – AHU-6 IN FAN ROOM NO. 2 (SOUTH) ............................................................................. 32 SITE PHOTOS WITH NOTES – BASEMENT AREA - SEAWATER PIPING & PAVEMENT HEATING ............................ 33 SITE PHOTOS WITH NOTES – BASEMENT AREA – MECHANICAL ROOM 19 & ELECTRICAL RM 18 ...................... 34 SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 3 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC EXECUTIVE SUMMARY – HEAT PUMP ALTERNATIVES TO SUPPLY AHU-5 & PAVEMENT HEAT 20 Year Life Cycle Cost Comparison Of Heat Pump Alternatives A, B, & C: Alternative B:Alternative C: Alternative A:One Heat Pump Two Heat Pumps One Heat Pump In Mech Room 19 In Mech Room 19 On Roof Level Of Basement For Of Basement For Description Of Financial Component To Supply AHU-5 Pavement Heat AHU-5 + Pvt Heat Total Project Installation Cost -$354,760 -$396,240 -$662,350 Electricity for glycol circ pumps - Year 1 $5,620 $5,620 $7,868 Present worth of electricity for glycol circ pumps over 20 year life cycle*-$112,401 -$112,401 -$157,361 Electricty required for heat pump - Year 1 $28,755 $23,963 $52,718 Present worth of electricty required for heat pumps over 20 life cycle*-$575,103 -$479,263 -$1,054,366 Maintenance of glycol/heat pumps - Yr 1 $1,800 $1,200 $2,500 Present worth of glycol and heat pump maintenance over 20 year life cycle**-$44,237 -$29,491 -$61,440 #2 heating oil saved by heat pumps - Yr 1 $61,636 $51,363 $113,000 Present worth of #2 heating oil saved by heat pumps over 20 yr life cycle***$1,514,765 $1,262,296 $2,777,085 Net Present Worth of Project $428,264 $244,901 $841,568 Years To Payback Initial Investment 10.8 Years 13.9 Years 10.6 Years Notes: * Grid electricity at industrial user rate from City of Seward, with 4% per year escalation ** Maintenance labor costs escalating at 6% per year, includes complete replacement of heat pump compressor bearings at year 12 *** Unit cost of #2 heating oil escalating at 6% per year - Discount rate applied to all financial components is 4% per year - Current industrial user rate for City of Seward grid electricity is $.086/KWH - Current cost of #2 heating oil to ASLC in Seward is $1.96/gallon SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 4 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC SCOPE OF SEA WATER HEAT PUMP EVALUATION FOR ALASKA SEA LIFE CENTER 1. Provide introduction to the purpose of the economic evaluation and a brief discussion of the function and history of ASLC. Express goals that ASLC has for both increasing energy efficiency and evaluating cost effective clean energy alternatives to fuel oil and grid electricity. Identify the financial and public relations benefits that can be derived from pursuing these goals in the current political and economic climate. 2. Evaluate trends of grid electricity and fuel oil costs from the past five years; and estimate escalation rates to be used for electricity and heating oil for a 20 year life cycle cost evaluation. 3. Evaluate monthly usage of fuel oil and electricity from the past five years and estimate future usage for a design life of 20 years. Include recommendations for increasing energy efficiency of ASLC facility that are noted during the course of technical site visit. 4. Evaluate daily and monthly raw seawater influent rates from the past five years, total capacity of seawater pumping, and raw seawater flow available for heat exchange to heat pumps that would be located in roof level mechanical room. 5. Evaluate seawater temperature variations from the past five years. Estimate the BTU’s of heat that can be extracted from ASLC raw seawater each month using a glycol loop and plate heat exchanger, and made available to heat pumps. 6. Identify proven heat pump systems that can utilize glycol loop heated by ASLC sea water during the heating season to supplement air handling units #5 & #6 located in roof level mechanical room, and pavement heating in basement area. Evaluate Coefficient of Performance (COP) of heat pumps selected and estimated electrical energy input for annual operation. Provide results of heat pump mfg’s software simulation if suitable and available. 7. Identify several specifically sized heat pump/glycol pump systems that can be integrated simply into the existing infrastructure. Provide schematics and site photos to illustrate the location of basic equipment; routing of piping; indicate estimated sizes and capacities of pumps, piping, heat exchanger, heat pumps. 8. For each alternative illustrated, perform 20 year life cycle cost evaluation which compares present worth of capital cost, electricity used by circulation pumps and heat pumps, anticipated maintenance/replacement costs, and heating fuel saved. 9. Compile an Executive Summary which lists alternative heat pump systems, the associated Capital Investment Required, Net Present Worth, and Years to Payback. 10. Produce deliverable report in pdf format which includes data from above items, graphs, color photos and technical information in a simple easy to read format that begins with the executive summary and recommendations of improvement options evaluated. SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 5 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC INTRODUCTION The Alaska SeaLife Center (ASLC) is the only marine research aquarium in the State of Alaska and one of the northern most on the planet. The Seward Association for Advancement of Marine Science (SAAMS) is the non-profit corporation that established the Alaska SeaLife Center which was opened to the public in May 1998. The Exxon Valdez Oil Spill Settlement Fund provided $26 million to help build the $56 million facility. Other funding was provided through grants, revenue bonds, and corporate and private donations. The city of Seward donated the seven-acre waterfront site for the SeaLife Center. The facility was designed in 1996 by Livingston Slone, Inc., an architecture, planning and design firm based in Anchorage. While the SeaLife Center receives approximately 20% of its annual budget from visitor fees and retail sales; the remaining portion of the financial income needed to maintain the facility is derived from federal, private and foundation grant funding. With recent escalations in both electricity and heating oil costs, and reductions in federal funding, the SeaLife Center is motivated to reduce its monthly operational expenses through both energy efficiency and evaluating heat production methods that are more cost effective than continued direct use of heating oil and grid electricty. The SeaLife Center is also interested in reducing its current production of greenhouse gas (CO2) as part of the greater mission to preserve and protect the fragile marine environment of Alaska. The concept of extracting latent heat from seawater in Resurrection Bay has become of increasing interest as the bay remains ice free through the winter, and ASLC has two 24 inch diameter seawater intake pipes that draw flow from a depth of 275 feet. The original design flow capacity from each of these seawater intakes is 5,000 gallons raw seawater per minute, although this capacity has been reduced in practice to only half that due to bio fouling of the perforated openings at depth. Because the heat exchange system in place in the basement area only removes 4 degrees F from the raw seawater while heating a glycol loop, the raw seawater can be returned to the main life support system supply pipes for use in various flow through marine life tanks. Under the direction of CEO Ian Dutton and General Manager Darryl Schaefermeyer, the Alaska Sealife Center decided in January 2009 to evaluate the use of sea water heat pumps to supplement heating loads in the ASLC facility. In review of the existing heating equipment and design heating loads for the facility, it is evident that the largest continuous demands during the heating season of September through April are roof level Air Handling Units AHU-5 and AHU-6; and the 12,000 lineal feet of pavement heating radiant heat used in outdoor walkways. YourCleanEnergy LLC was secured to evaluate the economic benefits of seawater heat pumps to supplement demands of AHU-5, AHU-6, and pavement heating. The concept of using heat from seawater for building demands has been employed f or nearly 20 years in northern Europe, and more recently in other locations, including southeast Alaska:  Ted Stevens Marine Research Institute (TSMRI) – NOAA – Nat’l Marine Fisheries – Juneau,  Nagoya Public Aquarium, Japan  Stockholm, Sweden = Vartan Ropsten = largest seawater heat pumps on the planet  Bodo, Norway, pop 41,000, military base, district heating w/44.6F seawater  STATOIL Research Centre, Trondheim, Norway, district heating with seawater The basic concept examined in this evaluation is to employ heat pumps to “lift” latent heat from raw seawater at temperatures ranging from 35F to 55F, and transfer this heat energy into air handler units and pavement at a temperature of 120F. The air handler units AHU-5 and AHU-6 are roof level units that currently transfer heat from a boiler fired 185F glycol loop in to the supply air stream for the building. Both units are equipped with duct coils through which a mixture of outside air and return air is drawn. The rate of glycol supply to these duct coils is modulated to maintain a temperature of 55F through 70F air leaving the air handler. The total design demand of AHU-5 plus AHU-6 is 3,124 MBH (3,124,000 BTU/hour) which represents approximately 40% of the total facility design heating demand. Accordingly, installation of heat pumps to supplement a majority of the heating demand for AHU-5 and AHU-6 will translate to significant reduction of heating oil usage and monthly operational costs. SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 6 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC SUMMARY OF ASLC HEAT PRODUCTION AND DESIGN DEMANDS (NAMEPLATE CAPACITY) SUMMARY OF ASLC HEAT PRODUCTION & DESIGN DEMANDS (NAMEPLATE) Heat Production Equipment Delivers Heat To:MBH*% of Total Capacity Boiler No. 1 - Fuel Oil - 87.9% Eff 185F Main Glycol Loop 2911 38.60% Boiler No. 2 - Fuel Oil - 87.9% Eff 185F Main Glycol Loop 2911 38.60% Boiler No. 3 - Electric - 500 KW 185F Main Glycol Loop 1706 22.62% Electric Unit Heater (EUH-1)14 0.19% Total Heating Capacity 7542 *Fuel oil boilers rated at 24 gal #2 fuel oil/hr x 138 MBH/gal fuel oil x 87.9% eff = 2911 MBH Heat Demand Equipment Receives Heat From:MBH % of Total Demand Pavement Heating - 12,000 LF 185F Main Glycol Loop via HX-1 1204 15.27% AHU-5 185F Main Glycol Loop 1782 22.61% AHU-6 185F Main Glycol Loop 1342 17.02% AHU-4 185F Main Glycol Loop 521 6.61% AHU-7 185F Main Glycol Loop 488 6.19% AHU-8 185F Main Glycol Loop 244 3.10% AHU-1 185F Main Glycol Loop 144 1.83% AHU-2 185F Main Glycol Loop 130 1.65% AHU-3 185F Main Glycol Loop 78 0.99% Total AHU Demand 4729 59.99% Duct Coil HC-1 (Lobby)185F Main Glycol Loop 170 2.16% Duct Coils HC-1 thru HC-24 185F Main Glycol Loop 396 5.02% Ceiling Unit Heaters (CUH -1, 2, 3)185F Main Glycol Loop 140 1.78% Wall Unit Heaters (UH-1, 2, 3)185F Main Glycol Loop 74 0.94% 1" Tube Fin BB Heaters (@600 LF)185F Main Glycol Loop 468 5.94% 1-1/4" Tube Fin BB Heaters (@200 LF)185F Main Glycol Loop 286 3.63% Total Unit Heater Demand 1534 19.46% Domestic Hot Water Tank, 630 Gal 185F Main Glycol Loop 416 5.28% Total Design Heat Demand 7883 Notes: 1. Heating demands listed above taken from 1996 Livingston Slone Design Drawings 2. Max monthly fuel oil usage was 18,442 gal/mo in Mar 07 = 3421 MBH avg demand SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 7 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC CONCEPT GUIDELINES FOR SUPPLYING AHU-5 AND AHU-6 WITH SEAWATER HEAT In the interest of reducing the capital cost of new heat pumps to supply AHU-5 and AHU-6, the following suggestions were made by ASLC staff during the initial scoping site visit by YourCleanEnergy:  Make use of the existing seawater to glycol plate and frame heat exchanger (HX-2) that is currently located in the north wing of the basement. This heat exchanger is already fed by influent seawater piping which is pumped from the main seawater intake well. HX-2 could be used as means of transferring heat from seawater into the existing chilled water glycol loop and up to new heat pumps installed in roof level mechanical rooms.  Make use of the existing 20 HP, 240 gpm chilled glycol circulation pump (PMP-15) and the 3”, 4” and 5” copper chilled glycol piping that is connected to cooling coils in both AHU-5 and AHU-6.  Make use of the cooling duct coils which are currently installed in AHU-5 and AHU-6 as a means of transferring heat from new heat pumps into the air handlers.  Make use of existing floor space adjacent to or nearby AHU-5 and AHU-6 for new heat pumps to be installed in rooftop mechanical rooms.  Make use of existing Motor Control Center (MCC) in Fan Room 1 and 2 to supply 480V 3 phase electric power to new heat pumps supplying AHU-5 and AHU-6. SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 8 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC EXISTING ELECTRICAL COSTS FOR ASLC IN SEWARD, ALASKA In order to plan energy efficiency projects for buildings in Seward, it is very useful to see the recent trend of rising energy costs. ASLC is currently charged a commercial electric rate by the Seward Electric Utility that consists of the following price components as illustrated with actual January 2009 billing: Primary Additional Peak Demand CEA Fuel Charge Monthly Charge Total $0.0706/KWH $0.0408/KWH $13/KW $0.0548/KWH $30/month $0.1371/KWH It is anticipated that ASLC will soon increase its monthly electricity usage and qualify for the City’s more favorable industrial rate, due the installation of new 500 KW electric boiler this month, and large demand heat pumps in the near future. Thus this heat evaluation is based on ASLC receiving the industrial rate, which is significantly lower in cost, as this estimation from January 2009 clearly indicates: Primary Additional Peak Demand CEA Fuel Charge Monthly Charge Total $0.00574/KWH $0/KWH $9.51/KW $0.0548/KWH $30/month $0.086/KWH Seward Electric Utility purchases firm power from Chugach Electric Association (CEA) with the exception of local diesel generation when Chugach power is interrupted by avalanches or other events. Therefore future price escalations in electricity cost in Seward are closely tied to those of Chugach Electric. The unit price of grid electricity from Chugach Electric has risen at a rate of approximately 6% per year for the past seven years. This increase has been tempered by the fact that 15% of CEA’s generation is from hydro-electric which has stabilized the retail cost of electricity; and load sharing between utilities on the rail belt grid of Alaska has prevented any one utility from subjecting customers to rapid price escalations. The primary factor expected to determine the escalation rate of Seward’s grid electricity is the cost of natural gas generation which has risen rapidly due to lack of competition in the region for this commodity. Several large oil and gas producers have an effective monopoly on gas reserves in Cook Inlet and new supplies have not yet been developed or transported in to reduce or stabilize the cost of natural gas. SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 9 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC The economic evaluations contained in this report are based on the rate of grid electricity from City of Seward escalating at an average rate of 4% per year for the next 20 years. The addition of local hydro electric power to the Seward City grid could further stabilize the retail price by reducing dependence on natural gas generation by Chugach Electric and by providing some alternative to emergency diesel generation during those times when supply from Chugach is interrupted. Electricity usage by ASLC has little variation through the year due to the large amount of continuous loads from HVAC, indoor lighting and life support systems. There is great scope to reduce some of this dem and through energy efficiency and reduction of HVAC ventilation rates during times of low occupancy. Other methods of reducing electricity use is to install variable speed controls on selected glycol pumps and exhaust fans, and placing the domestic hot water heat tape system on a timer. SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 10 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC HEATING OIL USAGE BY ASLC The primary heating plant of ASLC consists of two Cleaver-Brooks Model CB 100-80-125hw #2 fuel oil fired boilers, installed new in 2003, each with a rated output capacity of 2911 MBH. These boilers indirectly heat a 185F loop of 40% propylene glycol (Dowfrost) that in turn circulates through the facility to baseboard heaters, unit heaters, duct coils in Air Handling Units, pavement heating heat exchanger (HX- 1) and a 630 gallon domestic hot water tank. As shown previously on Page 5, the largest design demands of the facility during the September through April heating season are currently AHU-5 (22% of total demand), AHU-6 (17% of total demand), and pavement heating (15% of total demand). SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 11 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC RECENT AND PROJECTED HEATING OIL COSTS FOR ASLC ASLC purchases large quantities of #2 heating oil at bulk rate, actual price paid per gallon for recent years is shown below. W hile there has been an accelerated price increase for unit cost of crude oil products in the past two years, the overall price escalation has been on a baseline of 8.2% per year from January 2003 ($1.22/gallon) through March 2009 ($1.96/gallon). The recent economic recession and associated reduction in crude oil demand in the USA is likely to keep heating oil prices from escalating at the high rates of 2007 through 2008 for several years. For the purpose of economic evaluation of alternatives in this report, a conservative escalation rate of 6% per year is used, see second graph below. The global shortage of crude oil supplies and growing global demand, especially that of China and India, will increase escalation rates, however it is not certain how soon or how acute this will affect actual bulk heating oil prices in Alaska. At current retail electricity and fuel oil rates (March 2009), heating with #2 heating oil still remains 1.5 times more cost effective than heating with grid electricity: Cost of making 100,000 BTU of electric heat (element heater, $0.086/KWH) = $2.52 Cost of making 100,000 BTU with #2 heating oil (using 87.9% eff boiler, $1.96/gal) = $1.62 SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 12 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC RECOMMENDATIONS FOR INCREASING ENERGY EFFICIENCY OF ASLC FACILITY After conducting two sites visits and reviewing design drawings and reports, it i s recommended that ASLC consider the following improvements in energy efficiency prior to and/or in coordination with efforts to install seawater heat pump systems. These improvements will provide immediate reductions in heating and electrical costs, those with the lowest investment cost and highest payback should be done first. Reduce exhaust fan run times and/or rates. Exhaust fans have no heat recovery systems on them and most or all appear to running 24/7 regardless of occupation or need. Consequently a notable fraction of building heat created by burning fuel oil is exhausted to waste unnecessarily. The most cost effective way to reduce this loss of heat is to place fans on timer devices which restrict operation to times when the section of the building served by fan is occupied. Another method of controlling fans is with variable speed drive, or multi-speed drive. The effect of intermittent ventilation can be tested by simply trying different operation schedules, making sure that air quality, odors, life safety issues remain satisfactory. Install timer to control heat tape operation on domestic water line to labs. Heat tape is typically a very large and continuous electrical load which can be timer controlled. At present, making heat with electricity at $0.12/KWH is twice as expensive as making heat with boilers at 85% efficiency with fuel oil at $2/gallon. One modification that will yield high return is to place the domestic water supply line heat tape on a timer control. The tape extends the entire length of the domestic water supply line from the boiler room to point of use in labs. It may be very cost effective to turn off the tape from 6pm till 6am (12 hours/day) and still deliver heated water during normal operating hours. That would cut this electrical usage in half and still allow domestic water to preheat before use during the day. CO2 sensors for the AHU’s require calibration. The rate that cold outside enters the various air handling units in the facility is based on carbon dioxide levels in the return air, to optimize the use of already heated return air. The CO2 sensors have not been calibrated since 1998 and there is great possibility that inaccurate sensors may be causing over or under ventilation of building interior spaces. Control of pavement heating system. More precise control of outdoor pavement temperature will lead to reductions in heating demand. This is attractive to address considering that any excess heat applied to outdoor pavement is wasted outside the building envelope. Currently the pavement snow melting system operates continuously when outside temperature falls below 32F, regardless of snow or ice accumulation. A moisture sensor and slab temperature sensor should be added to the system so that demand of outdoor radiant heat loops can be reduced or eliminated at times when no snow is falling. Variable Speed Drives For Main Glycol Loop Circulation. Pumping energy can be saved cost effectively by adding variable frequency drives to the pumps circulating heated glycol (185F) to various heating loads in the facility. These pumps currently run at full speed regardless of heat demand. Install insulating shroud on boiler/glycol HX. The plate & frame heat exchanger located in the basement that transfer heat from boiler water to the main 180F glycol loop is completely un-insulated and is continuously losing large quantities of heat to the boiler room area. Insulation will control this loss. Install door sweeps on interior doors of main entrance. The main entrance employs an arctic entry which can reduce heat loss significantly from a building with high volume traffic. However the interior metal door sets have no sweep seals on the bottom of doors so cold air created by conduction through exterior doors pours at an uncontrolled rate under interior doors and into lobby area in winter months. Consider installing double layer cellular shades on selected north facing windows. ASLC has a large amount of glazing area with double pane gas filled windows whi ch contribute to building envelope heat loss. Windows that face north, north east or north west allow indirect lighting however they do not achieve any heat gain from direct solar exposure; cellular shades may installed and left in the down position when the space is unoccupied. This will add an estimated R5 value to the window and reduce heat loss during winter months. The cellular shades must fit tightly inside window frame and be positioned no more than ¾ inch off the face of glass to reduce convection air currents. SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 13 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC MONTHLY SEA WATER TEMPERATURES AND HEAT ENERGY AVAILABLE Seawater temperatures recorded for the past five years (2003 through 2008) at the Alaska SeaLife Center’s raw seawater influent well were compiled to determine the average seawater temperature for each month. The maximum monthly seawater temperature (56F) and minimum monthly seawater temperature (37F) were also identified. As shown in the graph below, it is evident that the large mass of seawater contained in Resurrection Bay is absorbing a significant quantity of solar heat during the summer months and releasing the same heat slowly through the winter heating season. The amount of heat contained in the influent seawater that can be used to supply heat pumps is a function of the seawater flow rate, seawater temperature, and the amount of temperature drop achieved in the seawater heat exchanger. The graph below shows heat available at various flow rates when the heat exchanger lowers seawater temperature to a minimum of 36F (seawater will freeze at 28.4F). The combined heat demand for AHU-5 and Pavement Heating is also shown for the purpose of comparison. SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 14 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC EXISTING AIR HANDLERS AHU-5 AND AHU-5 IN ROOF LEVEL FAN ROOMS Design specifications for existing air handler units AHU-5 and AHU-6: Unit Make Model Year Air Flow Fan HP Heating Coil Capacity AHU-5 Trane MCC 66 1996 30,000 CFM 30 HP Triple Row 1782 MBH AHU-6 Trane MCC 40 1996 22,600 CFM 25 HP Single Row 1342 MBH Sequence Of Operation (per 1996 Johnson Control Design): Start/Stop: AHU-5 operates based on user defined 365 day occupancy schedule and starts Exhaust Fan EF-5. AHU-6 operates continuously. Exhaust Fan EF-6 operates continuously. Supply Air Temperature Control: When fan is operating, Make Up Air dampers modulate as required to maintain either 600 PPM CO2 in Return Air; or 55 deg F Make Up Air temperature set point. Heating and cooling coil valves modulate in sequence as required to maintain discharge set point of 55 degree F. SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 15 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 16 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC HEAT PUMP OPERATION AND COEFFICIENT OF PERFORMANCE Coefficient Of Performance (COP) for a heat pump is the ratio of total heat output to electricity input. For seawater heat pump projects, a minimum COP value of 3.0 is desirable and can lead to viable economic returns. Seawater heat pumps are water to water heat pumps that operate by using electricity powered compressors in combination with the physical properties of an evaporating and condensing fluid known as a refrigerant. The refrigerant used in the heat pumps in this evaluation is known as R-134a. HOW A HEAT PUMP WORKS TO LIFT LOW TEMP HEAT TO A HIGHER TEMP COMPRESSOR LIQUIDHOT VAPOR VERY HOT VAPOR WARM VAPOR EXPANSION VALVE R-134a REFRIGERANT IS USED IN HIGH EFFICIENCY ROTARY SCREW COMPRESSOR HEAT PUMPS EVAPORATORCONDENSOR 41 F 33 F 98 F 120 F SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 17 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC SELECTION OF HEAT PUMP EQUIPMENT SUITABLE TO SUPPLY AHU-5 & 6, PAVEMENT HEAT The process of removing latent heat from raw seawater and making that same heat useful for large air handling units is neither simple nor conventional. The engineering challenge of achieving this for ASLC is made greater by the requirement of using heat transfer fluid with high concentrations of propylene glycol that increase flow viscosity and reduce heat capacity. There are only several manufacturers in the USA at this time who have considerable experience with manufacturing water to water heat pumps that can lift commercial quantities of heat energy from a temperature range of 35F to 50F on the evaporator side to as great as 120F on the condenser side. In this evaluation, simulations that define the glycol flow rates, evaporator and condenser temperatures, coefficient of performance (COP), electricity demand and heat output, are based Trane Model RTWD Hi Efficiency 2-Pass Evaporator 80 and 90 Ton Capacity units. These heat pumps are commercially available as compact self contained units which can be shipped to ASLC, placed on concrete foundations, and piped and wired in place. Design specifications for heat pumps included in this evaluation to supply AHU-5 and AHU-6: MFG Model Capacity Heat Output Power Req’d Dimensions Operating Weight Trane RTWD 80 Tons 960 MBH 480v/3ph/60Hz 10’7”L x 6’4”H x 3’W 5733 LBS Trane RTWD 90 Tons 1080 MBH 480v/3ph/60Hz 10’7”L x 6’4”H x 3’W 5792 LBS SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 18 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC RESULTS OF SIMULATION WITH ASLC SEAWATER TEMPS AND TRANE RTWD HEAT PUMPS Using average seawater temperatures dropping 2 degrees F through a plate heat exchanger with 25% propylene glycol, simulation results were provided by Trane for their 80 Ton and 90 Ton RTWD units: 25% PG 125 GPM on evap 25% PG 160 GPM on evap 25% PG 90 GPM on condensor 25% PG 95 GPM on condensor Ent. Evap Heating MBH kW COP Heating MBH kW COP Jan 41.2 782.7 68.53 3.35 955.9 81.94 3.42 Feb 39.3 754.4 67.84 3.26 921.4 81 3.33 March 38.2 738.1 67.45 3.21 901.4 80.46 3.28 April 37.8 732 67.3 3.19 894.2 80.26 3.26 May 38.1 736.5 67.41 3.20 899.6 80.41 3.28 June 39 749.9 67.74 3.24 915.9 80.85 3.32 July 39.6 758.9 67.95 3.27 926.8 81.15 3.35 August 40.3 769.3 68.21 3.30 939.5 81.49 3.38 September 43.7 820.2 69.44 3.46 1001.6 83.17 3.53 October 45.8 852.1 70.2 3.56 1040.3 84.21 3.62 November 45.6 849 70.13 3.55 1036.6 84.11 3.61 December 43.3 814.3 69.29 3.44 994.2 82.97 3.51 Worst 35 690.6 66.29 3.05 843.7 78.89 3.13 Best 50 use TOPSS ……use TOPSS …… RTWD080 RTWD090 The above results can then be applied to Alternative A of this evaluation which designates one 90 Ton unit supplying heat to AHU-5 (AHU-5 is estimated to be 30% of the actual total ASLC heating demand). The table below shows heat pump electricity and glycol pumping costs based on the industrial rate of $0.086/KWH and heating oil savings based on purchase price of bulk #2 heating oil at $1.96/gallon. 90 Ton AHU-5 Heat Heat #2 #2 Glycol Heat demand % of full Pump Pump Heating Heating Pumps Pump Electric as 30%load heat Days Electric Elect Oil Oil Elect Output Demand of total pump is per Usage Cost Saved Saved Cost Month (MBH)COP (KW) (MBH/mo)running Month (KWH)($)(gal)($)($) Jul 927 3.35 81.2 256 28%31 16,677 $1,434 1,539 $3,016 $477 Aug 940 3.38 81.5 276 29%31 17,811 $1,532 1,659 $3,251 $477 Sep 1,002 3.53 83.2 302 30%30 18,056 $1,553 1,757 $3,443 $462 Oct 1,040 3.62 84.2 424 41%31 25,535 $2,196 2,548 $4,995 $477 Nov 1,037 3.61 84.1 578 56%30 33,767 $2,904 3,362 $6,589 $462 Dec 994 3.51 83.0 590 59%31 36,633 $3,150 3,546 $6,950 $477 Jan 956 3.42 81.9 665 70%31 42,411 $3,647 3,997 $7,834 $477 Feb 921 3.33 81.0 612 66%28 36,154 $3,109 3,322 $6,512 $431 Mar 901 3.28 80.5 562 62%31 37,323 $3,210 3,378 $6,621 $477 Apr 894 3.26 80.3 430 48%30 27,789 $2,390 2,501 $4,902 $462 May 900 3.28 80.4 326 36%31 21,680 $1,864 1,959 $3,840 $477 Jun 916 3.32 80.9 323 35%30 20,529 $1,765 1,879 $3,682 $462 Annual Totals =5,344 334,364 $28,755 31,447 $61,636 $5,620 SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 19 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC SCHEMATIC OF EXISTING CHILLED WATER SUPPLY TO AHU-5 + AHU-6 SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 20 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC SCHEMATIC OF ALTERNATIVE A: ONE HEAT PUMP IN ROOF FAN ROOM #1 TO SUPPLY AHU-5 SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 21 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC COST ESTIMATE - ALTERNATIVE A: ONE HEAT PUMP TO SUPPLY AHU-5 Installed Installed Unit Total Item Description Quantity Unit Price Price Basement Mechanical Room at HX-2 install in-line flow meter on Pump PMP-15 discharge line 1 each $1,500 $1,500 install VFD on exist 5 hp glycol pump PMP-15 1 each $3,000 $3,000 install new 8" Sch 40 pvc piping to return seawater to process 100 LF $140 $14,000 Existing Chilled Water Lines From HX-2 to Roof install 3" ball valves on supply and return to AHU-6 2 each $300 $600 install 4" ball valves on supply and return to AHU-5 2 each $400 $800 Shut down chilled water system, drain piping 1 day $1,200 $1,200 Re-charge chilled water system with new 25% prop glycol 1 day $1,200 $1,200 New prop glycol for 25% PG chilled water loop 500 gal $20 $10,000 Rooftop Fan Room 1 (North) new 4" copper supply and return piping to heat pump 180 LF $100 $18,000 new 4" ball valves on supply/return piping to heat pump 10 each $400 $4,000 new glycol circ pump 120 GPM @50ftTDH w/VFD 1 each $8,000 $8,000 install new 2" ball valves on duct coil inlet piping 3 each $200 $600 in-line flow meter on 4" copper supply to heat pump 1 each $1,500 $1,500 tube & shell HX for chilled 25%PG / 40%PG transfer 2 each $25,000 $50,000 foundations and insulation for tube and shell HX's 2 each $2,000 $4,000 concrete foundation w/anchor bolts for new 90 ton heat pump 1 LS $1,000 $1,000 90 Ton Rotary Screw Hi Eff 2-pass Evaporator Heat Pump*90 ton $900 $81,000 Ship heat pump from Seattle Dock to Seward Dock 1 LS $5,000 $5,000 Install heat pump in roof area with crane + pallet jack/rollers 1 day $12,000 $12,000 On site training session with factory rep 2 day $1,200 $2,400 Start up services/commissioning**3 day $1,200 $3,600 Sound reduction package for heat pump 1 each $3,500 $3,500 OSHA required refrigerant monitor for R-134a 1 each $6,500 $6,500 Electrical Supply & Controls new 480v 125 amp breaker in exist MCC 2 each $2,000 $4,000 new 480v 125 amp cable from heat pump to exist MCC 60 LF $100 $6,000 integrate controls of new heat pump with exist Trane AHU-5 1 LS $10,000 $10,000 Total Installation Price for heat pump system $253,400 15% for final mechanical design & procurement services $38,010 5% for seismic structural analysis $12,670 5% for sound attentuation analysis $12,670 5% for construction inspection services $12,670 10% Contingency $25,340 Total Project Price - Alternative A $354,760 Total Project Cost/Ton Heat Pump Capacity Installed $3,942 *Heat pump price includes 2 yr warranty on all parts, 1 yr warranty on parts and labor **Replacement of 100,000 hr compressor bearings will be required at Year 12, present day cost of $12,000 SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 22 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC SCHEMATIC OF ALTERNATIVE B: ONE HEAT PUMP IN BASEMENT RM 19 FOR PAVEMENT HEAT Energy usage, production, and costs per month for Alternative B (one 90 Ton heat pump supplying pavement heat) with electricity at $0.086/KWH and #2 heating oil at $1.96/gallon: 90 Ton Heat Pavement % of Heat Heat #2 #2 Glycol Heat Pump Heating full load PumpElectPump HeatingFuel OilHeating Pumps Pump Electric Demand heat Days ElectricUnitElectric Oil Unit Oil Electric Output Demand 25% of total pump is per UsageCostCost SavedCostSaved Cost Month (MBH)COP (KW) (MBH/mo)running Month (KWH)($/KWH)($)(gal)($/gal)($)($) Jul 927 3.35 81.2 213 23%31 13,897 $1,195 1,282 $2,513 $477 Aug 940 3.38 81.5 230 24%31 14,843 $1,276 1,382 $2,709 $477 Sep 1,002 3.53 83.2 252 25%30 15,046 $1,294 1,464 $2,869 $462 Oct 1,040 3.62 84.2 353 34%31 21,280 $1,830 2,124 $4,162 $477 Nov 1,037 3.61 84.1 482 46%30 28,139 $2,420 2,802 $5,491 $462 Dec 994 3.51 83.0 492 49%31 30,527 $2,625 2,955 $5,792 $477 Jan 956 3.42 81.9 554 58%31 35,342 $3,039 3,331 $6,528 $477 Feb 921 3.33 81.0 510 55%28 30,128 $2,591 2,769 $5,427 $431 Mar 901 3.28 80.5 468 52%31 31,102 $2,675 2,815 $5,517 $477 Apr 894 3.26 80.3 358 40%30 23,157 $1,992 2,084 $4,085 $462 May 900 3.28 80.4 272 30%31 18,066 $1,554 1,633 $3,200 $477 Jun 916 3.32 80.9 269 29%30 17,107 $1,471 1,566 $3,069 $462 Annual Totals =4,453 278,637 $23,963 26,206 $51,363 $5,620 SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 23 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC COST ESTIMATE - ALTERNATIVE B: ONE HEAT PUMP IN BASEMENT ROOM 19 FOR PAVEMENT HEATING Installed Installed Unit Total Item Description Quantity Unit Price Price Basement Seawater Pump Room Tap into discharge piping of exist seawater pump 1 LS $2,000 $2,000 8" sch 80 PVC seawater piping from pump room to new HX 160 LF $140 $22,400 Flow meter for new 8" seawater piping 1 each $2,000 $2,000 New plate & frame HX (seawater to 25% prop glycol, 1252 MBH)1 each $80,000 $80,000 in-line flow meter on sch 80 glycol piping 1 each $2,000 $2,000 5 hp glycol pump with VFD 1 each $5,000 $5,000 new 6" Sch 40 pvc chilled glycol piping (HX to Rm 19)280 LF $100 $28,000 Along New Chilled Glycol Piping 6" ball valves on supply and return 8 each $300 $2,400 Charge new chilled glycol system with 25% prop glycol 1 day $1,200 $1,200 New prop glycol for 25% PG chilled water loop 300 gal $20 $6,000 Room 19 - Heat Pump Room 4" copper supply and return piping (pavemnt heat to Rm 19)120 LF $100 $12,000 new 4" ball valves on supply/return piping to heat pump 4 each $400 $1,600 new glycol circ pump 120 GPM @50ftTDH w/VFD 1 each $5,000 $5,000 in-line flow meter on 4" copper supply to Pavement Heating System 1 each $2,000 $2,000 concrete foundation for new 90 ton heat pump 1 each $1,000 $1,000 90 Ton rotary screw hi eff 2-pass evap heat pump*90 ton $900 $81,000 Ship heat pump from Seattle Dock to Seward Dock 1 LS $5,000 $5,000 Install heat pump in Room 19 thru hatch with crane 2 day $2,000 $4,000 Sound reduction package for heat pump 1 each $3,500 $3,500 OSHA required refrigerant monitor for R134-A 1 each $6,500 $6,500 On site training session with factory rep 2 day $1,200 $2,400 Start up services and commissioning**3 day $1,200 $3,600 Instrumentation wiring, testing & commissioning 1 LS $5,000 $5,000 new 480v 250 amp breaker in exist MCC 1 each $2,000 $2,000 new 480v 250 amp cable from exist MCC to Rm 19 120 LF $90 $10,800 Sub panel with two 125 amp breakers in Rm 19 1 each $1,200 $1,200 125 amp cables from sub panel to each compressor on HP 120 LF $60 $7,200 Total Installation Price for heat pump system $304,800 15% for final design & procurement services $45,720 5% for construction inspection services $15,240 10% Contingency $30,480 Total Project Price - Rm 19 Alternative $396,240 Total Project Cost/Ton Heat Pump Capacity Installed $4,403 *Heat pump price includes 2 yr warranty on all parts, 1 yr warranty on parts and labor **Replacement of 100,000 hr compressor bearings req'd at Year 12, present day cost of $12,000/heat pump SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 24 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC SCHEMATIC OF ALTERNATIVE C: TWO HEAT PUMPS IN ROOM 19 OF BASEMENT FOR AHU-5 + PAVEMENT HEATING Energy usage, production, and costs per month for Alternative C (two 90 Ton heat pumps supplying pavement heat and AHU-5) with electricity at $0.086/KWH and #2 heating oil at $1.96/gallon: Two 90 Heat AHU-5 +% of Heat Heat #2 #2 Glycol Ton Heat PumpsPavementPvt Heat full load PumpElectPump HeatingFuel OilHeating Pumps Pumps ElectricHeat Demandas 55%heat Days ElectricUnitElectric Oil Unit Oil Electric Output Demandas 25%of total pump is per UsageCostCost SavedCostSaved Cost Month (MBH)COP (KW) of total(MBH/mo)running Month (KWH)($/KWH)($)(gal)($/gal)($)($) Jul 1,854 3.35 162 469 25%31 30,574 $2,629 2,821 $5,529 $668 Aug 1,879 3.38 163 506 27%31 32,654 $2,808 3,041 $5,961 $668 Sep 2,003 3.53 166 554 28%30 33,102 $2,847 3,220 $6,312 $647 Oct 2,081 3.62 168 777 37%31 46,815 $4,026 4,672 $9,157 $668 Nov 2,073 3.61 168 1,060 51%30 61,907 $5,324 6,164 $12,081 $647 Dec 1,988 3.51 166 1,082 54%31 67,160 $5,776 6,501 $12,742 $668 Jan 1,912 3.42 164 1,219 64%31 77,753 $6,687 7,328 $14,362 $668 Feb 1,843 3.33 162 1,122 61%28 66,283 $5,700 6,091 $11,938 $604 Mar 1,803 3.28 161 1,030 57%31 68,425 $5,885 6,193 $12,138 $668 Apr 1,788 3.26 161 788 44%30 50,946 $4,381 4,585 $8,987 $647 May 1,799 3.28 161 598 33%31 39,746 $3,418 3,592 $7,041 $668 Jun 1,832 3.32 162 592 32%30 37,636 $3,237 3,444 $6,751 $647 Annual totals:9,797 613,001 $52,718 57,653 $112,999 $7,868 SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 25 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC COST ESTIMATE - ALTERNATIVE C: TWO HEAT PUMPS IN BASEMENT ROOM 19 FOR PAVEMENT HEAT + AHU-5 Installed Installed Unit Total Item Description Quantity Unit Price Price Basement Seawater Pump Room Tap into discharge piping of exist seawater pump 1 LS $2,000 $2,000 8" sch 80 PVC seawater piping from pump room to new HX 220 LF $140 $30,800 Flow meter for new 8" seawater piping 1 each $2,000 $2,000 New plate & frame HX (seawater to 25% prop glycol - 1230 MBH)1 each $80,000 $80,000 in-line flow meter on sch 80 glycol piping 1 each $2,000 $2,000 7.55 hp glycol pump with VFD 1 each $10,000 $10,000 new 6" Sch 80 pvc chilled glycol piping (HX to Rm 19)280 LF $100 $28,000 Along New Chilled Glycol Piping 6" ball valves on supply and return 8 each $300 $2,400 Charge new chilled glycol system with 25% prop glycol 1 day $1,200 $1,200 new 4" copper glycol piping from basement to AHU-5 on roof 600 LF $100 $60,000.00 new 4" ball valves on supply/return piping to heat pump 8 each $400 $3,200 New prop glycol for 25% PG chilled water loop 500 gal $20 $10,000 Basement Room 19 - Heat Pump Room 4" copper supply and return piping (pavemnt heat to Rm 19)120 LF $100 $12,000 new 4" ball valves on supply/return piping to heat pump 4 each $400 $1,600 new glycol circ pump 240 GPM @50ftTDH w/VFD 1 each $10,000 $10,000 in-line flow meter on 4" copper supply to Pavement Heating System 1 each $2,000 $2,000 concrete foundation for new 90 ton heat pump 2 each $1,000 $2,000 two 90 Ton rotary screw hi eff 2-pass evap heat pumps*180 ton $900 $162,000 Ship heat pump from Seattle Dock to Seward Dock 2 each $5,000 $10,000 Install heat pump in Room 19 thru hatch with crane 2 day $2,000 $4,000 Sound reduction package for heat pump 2 each $3,500 $7,000 OSHA required refrigerant monitor for R134-A 1 each $6,500 $6,500 On site training session with factory rep 2 day $1,200 $2,400 Start up services and commissioning**3 day $1,200 $3,600 Instrumentation wiring, testing & commissioning 1 LS $10,000 $10,000 new 480v 250 amp breaker in exist MCC 2 each $2,000 $4,000 new 480v 250 amp cable from exist MCC to Rm 19 240 LF $100 $24,000 Sub panel with two 125 amp breakers in Rm 19 2 each $1,200 $2,400 125 amp cables from subpanel to each compressor on HP 240 LF $60 $14,400 Total Installation Price for heat pump system $509,500 15% for final design & procurement services $76,425 5% for construction inspection services $25,475 10% Contingency $50,950 Total Project Price - Rm 19 Alternative $662,350 Total Project Cost/Ton Heat Pump Capacity Installed $3,680 *Heat pump price includes 2 yr warranty on all parts, 1 yr warranty on parts and labor **Replacement of 100,000 hr compressor bearings req'd at Year 12, present day cost of $12,000/heat pump SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 26 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC MANAGING FREEZE PROTECTION OF HEAT TRANSFER LOOPS IN DUCT COILS Glycol solution adjustment is required: The existing chilled water system is charged with 40% propylene glycol and 60% water by volume. While 40% propylene glycol provides freeze protection down to minus 5 degrees F, it has a heat capacity too low to allow adequate heat transfer for the rotary screw compressor heat pumps that are commercially available and suitable for this project. In order to achieve convergence of heat transfer in both the evaporator and condenser of the heat pumps, the existing chilled glycol loop will have to be changed to either 25% propylene glycol or 35% ethylene glycol by volume. Using 25% propylene glycol will be a simple adjustment; however the risk of chilled water freezing in the duct coils of AHU-5 and AHU-6 must be addressed. This risk will be present when ambient temperatures are below 15 deg F and the heat pumps are not circulating 90F - 120F glycol through the duct coils. A possible method of avoiding glycol freeze in the duct coils is to add a plate and frame heat exchanger and circulation pump that circulates 40% glycol through the duct coils and the cold side of the heat exchanger, while the warm side of the heat exchanger receives 25% glycol supply from the heat pump by means of a second circulation pump. SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 27 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC SITE PHOTOS WITH NOTES – EXISTING CHILLED WAT ER HX AND PUMP SYSTEM IN BASEMENT SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 28 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC SITE PHOTOS WITH NOTES – EXISTING CHILLED WAT ER HX AND PUMP SYSTEM IN BASEMENT SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 29 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC SITE PHOTOS WITH NOTES – AHU-5 IN FAN ROOM NO. 1 (NORTH) SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 30 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC SITE PHOTOS WITH NOTES – AHU-5 IN FAN ROOM NO. 1 (NORTH) SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 31 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC SITE PHOTOS WITH NOTES – AHU-6 IN FAN ROOM NO. 2 (SOUTH) SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 32 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC SITE PHOTOS WITH NOTES – AHU-6 IN FAN ROOM NO. 2 (SOUTH) SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 33 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC SITE PHOTOS WITH NOTES – BASEMENT AREA - SEAWATER PIPING & PAVEMENT HEATING SEA WATER HEAT PUMP EVALUATION ALASKA SEA LIFE CENTER 3/28/09 PAGE 34 OF 34 “Celebrate the power of nature”TM …with YourCleanEnergy LLC SITE PHOTOS WITH NOTES – BASEMENT AREA – MECHANICAL ROOM 19 & ELECTRICAL RM 18