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HomeMy WebLinkAboutCEA & AK RENEWABLES - Agreement for Payment of Interconnection and Integration Studies - SignedDocuSign Envelope ID: C6E8241A-8A7D-4C28-BA39-E8401A1270AA AGREEMENT FOR PAYMENT OF INTERCONNECTION AND INTEGRATION STUDIES This Agreement for Payment of Interconnection and Integration Studies ("Agreement"), dated as of September 16, 2022, is entered into by and between Alaska Renewables LLC ("Asset Owner") and Chugach Electric Association, Inc. ("Utility"). The Asset Owner and the Utility are referred to collectively as the "Parties" and each, individually, as a "Party". RECITALS A. Asset Owner has applied for Interconnection of the Little Mount Susitna wind facility located near Little Mount Susitna in the Matanuska-Susitna Borough, Alaska ("Resource") with Utility's electrical system. Pursuant to Utility's Tariff, the Asset Owner is responsible for full payment of the costs Utility would not have incurred but for the Interconnection. Utility will estimate its costs related to the Asset Owner's proposed Interconnection. B. Subject to the terms and conditions below, Utility is willing to study and engage with Asset Owner to evaluate and, in accordance with the applicable provisions of the Tariff, any future Electric Reliability Organization's requirements, the requirements of the Amended and Restated Operations Agreement for Power Pooling and Joint Dispatch between Utility and Matanuska Electric Association ("Amended Pooling Agreement"), and otherwise in accordance with Good Utility Practice, allow for the Interconnection of the Resource ("Interconnection Services") pursuant to an Interconnection Agreement. C. The Parties recognize that the studies and analyses to be performed under this Agreement are a necessary precursor to negotiation of an Interconnection Agreement and Power Purchase Agreement and the Parties enter into this Agreement in good faith to conduct and support those studies and analyses to better inform the possible development and interconnection of the Resource for the mutual benefit of both Parties. AGREEMENT NOW, THEREFORE, in consideration of and subject to the mutual covenants contained herein, it is agreed: 1. WORK TO BE PERFORMED a. Scope of Work. Utility will complete the following tasks related to Asset Owner's proposed Interconnection Services: (i) a system interconnection study, (ii) a system integration study, and (iii) any other studies reasonably necessary to integrate the Resource into Utility's electric system in a manner such that all applicable operational and reliability rules, regulations, practices, criteria, and standards are met; provided that, such additional studies shall only be undertaken after Utility has given Asset Owner reasonable advance notice and opportunity to comment on any proposed additional studies (the "Work"). A preliminary proposal for the scope of Work necessary to analyze Utility's provision of the Interconnection Services is contained in DocuSign Envelope ID: C6E8241A-8A7D-4C28-8A39-E8401A1270AA Little Mount Susitna Study Payment Agreement Attachments A, B and E; provided that, the proposals contained in Attachments A, B and E and the cost proposal in Attachment C are not binding on Utility and are at all times subject to revision by Utility in its sole discretion. b. Right to Work Product. Asset Owner shall be included in the regular occurring meeting(s) among Utility and its consultants every two weeks or at an interval mutually agreed to be necessary, provided the same level of visibility into modeling and preliminary work products from consultants as Utility, and provided a copy of and have the right to use finalized work product resulting from Utility's (including its consultants') work under this Agreement; provided that, Asset Owner shall have no right to work product consisting of information or materials that are privileged, confidential, or proprietary to Utility or its consultants. c. Accuracy of Information. Except as a Party ("Providing Party") may otherwise specify in writing when it provides information to the other Party under this Agreement, the Providing Party shall use commercially reasonable efforts to verify the accuracy and completeness of information provided to the other Party for the purpose of completing the Work. The Providing Party shall promptly provide the other Party with any additional information needed to update information previously provided. d. Disclaimer of Warranty. In preparing and/or participating in the Work, as applicable, each Party and any subcontractors or consultants employed by it shall have to rely on information provided by the Providing Party, and possibly by third parties, and may not have control over the accuracy of such information. Accordingly, beyond the commitment contained in Section 1.c., no Party nor any subcontractor or consultant employed by it makes any warranties, express or implied, whether arising by operation of law, course of performance or dealing, custom, usage in the trade or profession, or otherwise, including without limitation implied warranties of merchantability and fitness for a particular purpose, with regard to the accuracy of the information considered, the content generated, or conclusions drawn during the course of completing the Work. Asset Owner acknowledges that it has not relied on any representations or warranties not specifically set forth herein and that no such representations or warranties have formed the basis of its bargain hereunder. e. Mutual Indemnification. Asset Owner agrees to indemnify, defend, and hold Utility harmless from any claims, losses, damages, fines, fees, penalties, deficiencies, expenses, including expenses of investigations, court costs and fees and expenses of attorneys arising from all of Asset Owner's negligent or more culpable acts and omissions arising under this Agreement. Utility agrees to indemnify, defend, and hold Asset Owner harmless from any claims, losses, damages, fines, fees, penalties, deficiencies, expenses, including expenses of investigations, court costs and fees and expenses of attorneys arising from all of Utility's negligent or more culpable acts and omissions arising under this Agreement. The indemnification, defense, and hold harmless obligations in this section survive the Agreement's termination. 0 DocuSign Envelope ID: C6E8241A-8A7D-4C28-8A39-Ea401A1270AA Little Mount Susitna Study Payment Agreement 2. COST RESPONSIBILITY AND BILLING a. General. Asset Owner will be responsible for the actual costs incurred by Utility that would not otherwise have been incurred but for Asset Owner's request. b. Deposit. Within ten (10) business days of Asset Owner's execution of this Agreement, Asset Owner shall pay Utility upfront one hundred percent (100%) of the good faith estimate of Utility's costs related to the proposed Services as set forth in Attachment C. If the good faith estimate is a range, the deposit shall be the average of the low and high ends of the range. Upon termination or completion of the Work, Utility shall refund to Asset Owner any funds paid or deposited by Asset Owner in excess of Utility's actual costs incurred performing the Work. Such refund, if any, shall be issued by Utility no later than thirty (30) days after Utility's receipt of notice of termination or the date that the Parties agree the Work is completed. c. Monthly Invoices. Utility shall provide Asset Owner with monthly invoices detailing the actual costs incurred by Utility in connection with its performance of the Work. Utility shall apply deposited funds against such invoices within five (5) days after issuance of each monthly invoice. If at any point the deposit is not sufficient to pay an invoice, Asset Owner shall remit payment to Utility to satisfy such invoice in full within 20 days of receipt of the invoice. Asset Owner shall be entitled to request documentation supporting such invoices only to the extent the information contained in such supporting documentation is not privileged or confidential to Utility. d. Late Payments. If Asset Owner fails to pay any sum when due, then, in addition to all other remedies available under this Agreement or at law (which Utility does not waive by the exercise of any right under this Section): i. all such payments shall bear interest at 10.5% a year (calculated daily and compounded monthly) starting on the date such payment is due until but excluding the date the overdue amount plus the applicable interest is paid; ii. if such failure continues for ten (10) days after written notice thereof, Asset Owner is deemed to be in breach of this Agreement and Utility may in its sole discretion immediately suspend or terminate performance of any additional Work under this Agreement. 3. INFORMATION Asset Owner agrees to provide all information requested by the Utility that is reasonably necessary to assist Utility to determine all facilities, terms, and conditions necessary for the provision of Interconnection Services for the Resource. 4. TERMINATION Asset Owner may terminate this Agreement for any reason and at any time upon thirty (30) days written notice to Utility. Upon receipt of such notice, Utility shall promptly terminate work under 3 DocuSign Envelope ID: C6E8241A-8A7D-4C28-8A39-E8401A1270AA Little Mount Susitna Study Payment Agreement this Agreement. Asset Owner shall be responsible for any costs incurred by Utility (including costs incurred for work completed on Utility's behalf) prior to the termination of such work. 5. LIMITATION OF LIABILITY This Agreement is not intended, nor shall it be interpreted, to constitute agreement by the Utility to allow Asset Owner to connect the Resource to the Transmission System, or agreement by the Utility to provide Interconnection of the Resource to the Transmission System, to permit Parallel Operation of the Resource with Utility's electrical system, or the provision by Utility to Asset Owner or any third party of any type of Transmission Service. Without limiting the generality of the foregoing, this Agreement is not intended, nor shall it be interpreted, to constitute agreement by the Utility to provide any aspect of the Interconnection Services. In no event will either Party (including subcontractors) be liable for indirect, special, incidental, punitive, or consequential damages of any kind including loss of profits, whether under this Agreement or otherwise, even if the Party has been advised of the possibility of such a loss. Nor shall either Party be liable for any delay in delivery or the non-performance or delay in performance of the Parties' obligations under this Agreement. 6. OTHER COVENANTS a. Interconnection Agreement and Power Purchase Agreement. As soon as practicable following completion of the Work under this Agreement the Parties shall enter into negotiations regarding a mutually acceptable Interconnection Agreement and Power Purchase Agreement. The Parties shall negotiate in good faith and use commercially reasonable efforts to bring about the execution and delivery of an Interconnection Agreement and Power Purchase Agreement. Notwithstanding the foregoing, Utility shall not be obligated to enter into an Interconnection Agreement or Power Purchase Agreement with Asset Owner if it would result in costs greater than those which the utility would have incurred if it had not made such purchases but had instead generated or purchased an equivalent amount of power. b. Government Approvals and Consents. Following successful negotiation and execution of an Interconnection Agreement and Power Purchase Agreement, the Parties shall use commercially reasonable efforts to cooperate and advocate to obtain all necessary board, regulatory, and other third -party approvals. Utility shall lead the effort to obtain necessary approvals from the Regulatory Commission of Alaska and Matanuska Electric Association as required per the applicable Amended Pooling Agreement. The Parties shall be solely responsible for their own costs associated with such efforts. c. Time of the Essence. Time is of the essence with regard to the Work to be performed under this Agreement, the negotiation and execution of an Interconnection Agreement, and the receipt of any necessary board, regulatory, or third -party approvals. The Parties will use commercially reasonable efforts to timely complete each task at the appropriate time. d. Non -circumvention. For a period of 12 months from the date of this Agreement, or for as long as Utility is actively pursuing an Interconnection Agreement or Power Purchase Agreement with Asset Owner, whichever is longer, Utility shall not, except in collaboration with 4 DocuSign Envelope ID: C6E8241A-8A7D-4C28-8A39-E8401A1270AA Little Mount Susitna Study Payment Agreement or with the prior express written consent of Asset Owner, seek to engage in the development of a competing or substitutionary wind project at the proposed Resource site defined in Attachment D that would knowingly conflict with the prioritization or location of the Resource. 7. MISCELLANEOUS a. Any notice or request made to or by either Party regarding this Agreement shall be made to the representative of the other Party in writing and addressed to the other Party as indicated below. utility Chugach Electric Association, Inc. P.O. Box 196300 5601 Electron Drive Anchorage, AK 99519 Attention: Sean Skaling, Sr. Manager of Business and Sustainable Program Development Phone: (907) 762-4192 E-mail: Sean skalin ,@,chugachelectric.com Asset Owner Alaska Renewables LLC 2595 Allen Adale Rd. Fairbanks, AK 99709 Attention: Matthew Perkins, CEO Phone: 518-424-4432 E-mail: matt@alaskarenewables.com All notices shall be delivered by email (with confirmation of transmission); and optionally also by personal delivery, nationally recognized overnight courier (with all fees pre -paid), or certified or registered mail (in each case, return receipt requested, postage pre -paid). Except as otherwise provided in this Agreement, a notice is effective only (a) upon receipt by the receiving Party, and (b) if the Party giving the notice has complied with the requirements of this section. b. No waiver by either Party of one or more defaults by the other in performance of any of the provisions of this Agreement shall operate or be construed as a waiver of any other or further defaults, whether of a like or different character. C. This Agreement constitutes the sole and entire agreement of the parties to this Agreement with respect to the subject matter contained herein and supersedes all prior and contemporaneous understandings, agreements, representations, and warranties, both written and oral, with respect to such subject matter. d. This Agreement or any part thereof may not be amended, modified, or waived other than by a writing signed by all parties hereto. DocuSign Envelope ID: C6E8241A-8A7D-4C28-8A39-E8401A1270AA Little Mount Susitna Study Payment Agreement e. This Agreement shall be binding, except as specified in Section l.a., upon the parties hereto, their heirs, executors, administrators, successors, and assigns. L This Agreement is for the sole benefit of the parties hereto and their respective successors and assigns and nothing herein, express or implied, is intended to or shall confer upon any other person or entity any legal or equitable right, benefit, or remedy of any nature whatsoever under or by reason of this Agreement. g. This Agreement shall be governed by the laws of the State of Alaska, without giving effect to any choice or conflicts of laws principles. h. Any legal suit, action, or proceeding arising out of this Agreement shall be instituted in the federal courts of the United States of America or the courts of the State of Alaska in each case located in the Municipality of Anchorage, Third Judicial District, and each Party irrevocably submits to the exclusive jurisdiction of such courts in any such suit, action, or proceeding. IN WITNESS WHEREOF, the Utility and Asset Owner have caused this Agreement to be executed by their respective corporate officers. utility: el"Signature Arthur W. Miller Printed Name Chief Executive Officer Title Asset Owner: [eR W: Mal{lu,w Pu�iws a.rtaa Signature Matthew Perkins Printed Name Chief Executive Officer Title [Attachments A-E follow] 0 DocuSign Envelope ID: C6E8241A-8A7D-4C28-8A39-E8401A1270AA Little Mount Susitna Study Payment Agreement Attachment A Interconnection and System Impact Study Scope Electric Power Systems, Inc. (EPS) will perform an interconnection and system impact study of the Asset Owner's proposed 122.4 MW wind installation for the Utility as described in Attachment E, or as later updated and agreed to by the Parties. Information to be provided by Asset Owner prior to beginning the interconnection study (unless otherwise indicated): 1) Data: a) Expected facility output during different times of the year (maximums and minimums) i) Voltage level of facility or facilities ii) MW and WAR capacity, or demand, at point of interconnection 2) Models (may be provided after initiating the study due to preliminary work needed from EPS): a) PSS/e transient stability model for the inverters / wind turbines in PSS/e version 34.5 or higher, 34.8.2 preferred. This includes a description of the expected operating modes (frequency droop, volt/var droop, etc.). The model must accurately include the low voltage ride through and frequency ride through characteristics of the plant, along with supporting documentation. b) PSS/e model for ancillary equipment (reactive compensation, energy storage systems, etc.). This includes the project step-up transformer and any equivalent collector system models. c) Short circuit model in ASPEN. This model must also provide accurate short circuit contributions and ride through modeling for low voltage conditions. 3) Drawings a) One -line and three -line drawings, including collector system. b) Diagram depicting point of interconnect/site overview 4) Datasheets (nameplates and manufacture data): a) Inverter/turbine datasheet/manufacturer data. b) Any other known devices (transformers, breakers, protection elements, voltage controls, etc.). As needed, Asset Owner may separately and at their expense hire a contractor to prepare portions of the information requested above. Any changes to design or substitutions of equipment prior to construction may require re -running studies at Asset Owner's expense. The design and performance of the models provided for study must be matched in the field when/if project is built. Any deviations from expected performance will require corrective action to fix to meet the modeled performance. Studies to be performed by EPS: See Attachment E. 7 DocuSign Envelope ID: C6E8241A-8A7D-4C28-8A39-E8401A1270AA Little Mount Susitna Study Payment Agreement Plans/Agreements: For planning purposes, below is a preliminary list of plans and agreements that will be needed prior to interconnection. • Interconnection plan and agreement • Verification of plan to comply with Railbelt Reliability Council's reliability standards • Verification of plan to comply with Power Pool's reliability requirements • Metering plan and agreement • Dispatch, SCADA, and telecommunications plan and agreement • Voltage, reactive power, and power factor control plan • Facility synchronization plan • Reliability guarantee • Maintenance coordination plan and agreement o Alternatively, plan and agreement for Utility to provide maintenance • Operational issue plan o Abnormal frequency plan o Abnormal voltage plan • Inspection requirements agreement o Commissioning plan o Energization plan o Witness agreements • Communications plan and procedure for normal and emergency operating conditions • Curtailment procedure agreement DocuSign Envelope ID: C6E8241A-8A7D-4C28-8A39-E8401A1270AA Little Mount Susitna Study Payment Agreement Attachment B Preliminary Proposal oflntepration Study Scope of Work An integration study will be conducted to determine the integration impacts and costs and benefits to the Utility's system and Power Pool resulting from the proposed Resource. The studies conducted will be consistent with typical integration studies to determine the economic impacts of the proposed renewable energy project to the Utility and/or Power Pool. The economic impacts include the benefits of adding the Resource (including reduced consumption of fuel and changes to operations and maintenance costs) and the impacts of how Utility would change its daily and hourly operations to accommodate the Resource (including increased ancillary services needed to regulate the Resource). Information (to be provided by Asset Owner) needed to perform integration study: • Date of commercial operation • Annual hourly modeled generation data (8760 data output) • Transmission losses (if any) prior to delivery to Utility's transmission grid • Battery specifications (if Asset Owner is proposing to include a battery or other storage device): o MW levels o Hours of storage o Cycle limits (per day, week, month, or year) o Roundtrip losses o Availability rate o Variable costs ($/MWh, $/hour, or $/full charge/discharge cycle) that affect operational decisions at the storage facility o Information on use of the battery: [final information here may require tri-lateral discussions with Asset Owner, Utility and NERA] ■ Will the battery be limited to charging from the renewable source, or will it be fully optimized with Utility's system (and or other utilities) to charge/discharge to/from grid when beneficial? ■ Will it be limited to shifting/shaving generation/load, or will it be able to provide spinning reserves, regulation and/or other ancillary services to Utility? 9 DocuSign Envelope ID: C6E8241A-8A7D-4C28-8A39-E8401A1270AA Little Mount Susitna Study Payment Agreement Attachment D Proposed Resource Site Little Mount Susitna Site Overview from Alaska Renewables proposal to Chugach Electric. The yellow polygon indicates the extent of the lease area. The gold line indicates the existing Beluga industrial roads. The orange line beginning at the Y is a proposed new access road that would branch off the existing road and climb up the Little Mount Susitna plateau where the wind turbine array would be located. The purple line shows the route of the existing transmission corridor between Beluga and Anchorage. The green line shows the route of new proposed transmission to connect with that corridor. 11 DocuSign Envelope ID: C6E8241A-8A7D-4C28-8A39-E8401A1270AA Little Mount Susitna Study Payment Agreement Attachment E Interconnection and System Impact Study pledK Pauer system PAS c«mda Evin— " Sean Skaling Manager of Business and Sustainable Program Development Chugach Electric Association, Inc. 5601 Electron Drive Anchorage, AK 99519 September 12, 2022 Subject: CEA / Alaska Renewables — Interconnection and System Impact Study — Proposal — Rev 2 Electric Power Systems (EPS) is pleased to present a proposal to Chugach Electric Association (CEA) to conduct an Interconnection and System Impact Study for a proposed 120 MW wind installation to be interconnected within the CEA service area. Alaska Renewables is the Independent Power Producer (IPP) and owner of the proposed facility. Based on the various tele-conferences with CEA, EPS has developed the following scope of work. We have also provided a budget estimate for this study of the proposed wind energy facility_ CEA has determined that this study should include an evaluation of the proposed interconnection and a detailed system impact study. As such, this revision of the proposal adds a significant number of tasks to the previous proposal to cover the system impact analysis as discussed with CEA. This revision also describes in more detail each of the study tasks to be performed. Scope of Work We have prepared the following list of tasks to be performed for the study of the proposed wind installation. 1. Facility modeling a. This task collects the data needed to develop the models of the project, for the power flow, transient stability, and short circuit analysis. The equipment ratings will be assessed based on project capacity. b. An equivalent model will be built from the collector system information. The model will be built using the industry accepted method for developing the equivalent model. The equivalent model is inserted in the power flow and dynamics model for the Railbelt and used for system -wide planning and operating studies. The equivalent model includes an equivalent generation model, transformers, line equivalent, and voltage control equipment to replicate the power, frequency, and voltage response of the project to changing grid side conditions_ The equivalent model is then used in all subsequent system studies. c_ The adequacy of the protection equipment will be assessed in accordance with CEA requirements and standard practices. This task evaluates whether the proposed facilities include the required protective equipment for the installation. This does not include an evaluation of the settings for the protective devices. Station one -line and three -line diagrams will be required to assess the interconnection design and equipment. 2. Interconnection and Steady State Power Flow Impact a. The adequacy of the proposed interconnection will be assessed from a steady state perspective by running power flows and evaluating the results in accordance with the Railbelt Transmission Planning Standard, AKTPL-001. The standard requires that the interconnection be evaluated with under various system conditions. The conditions include different seasonal load scenarios and different line topologies (all lines in service and all combinations of lines out W W W. EPSI NC.COM 4020 148th Ave NE, Suite C, REDMOND, WA 98052 12 DocuSign Envelope ID: C6E8241A-8A7D-4C28-8A39-E8401A1270AA Little Mount Susitna Study Payment Agreement CEA / ALASKA RENEWABLES - INTERCONNECTION AND SYSTEM IMPACT STUDY - PROPOSAL - REV 2 of service). Under all conditions, line loadings and substation voltages must remain within accepted limits to meet the criteria. b. Variations in the interconnection design will be evaluated such as different options for interconnecting to the existing transmission system. The benefits and risks associated with different interconnection configurations will be evaluated using the planning criteria as the standard for assessing the connection. The impact each configuration has on line loading conditions and voltage control will be assessed_ Transient Stability for the Interconnection a. The dynamic model of the project will be inserted into the Railbelt dynamic model. The dynamic model includes several parameters that describe the performance and response of the plant during transient events such as off nominal frequency and voltage conditions. Where appropriate, sensitivity cases will be run to assess the impact of adjustments in these parameters. The initialization of the model will also be evaluated during this task to ensure that the model will properly initialize for various initial conditions. b. Transient simulations will be run with the interconnection in place. The transient events will be modeled and simulated based on the AKTPL-001 standard. The standard specifies numerous system operating conditions and transient events that are required to be evaluated. The AKTPL-001 standard also provides the acceptable system response for each type of transient event. Cases will be run for various seasonal loading conditions, various equipment initially out of service, and numerous transient events. The transient response is assessed in terms of the frequency and voltage response of the system during the transient. The standard specifies the acceptable frequency and voltage response and what other types of response are acceptable, such as load shedding or system separation. c_ When appropriate, changes to the interconnection or changes to the dynamic parameters for the project will be studied whenever the initial simulations show an unacceptable system response to a transient event. 4. Transient Stability— System Impact a. This task will evaluate the impact of the project on the overall stability of the Railbelt. Specifically, system wide constraints such as transfer limit along the Alaska Intertie or the transfer limit along the Kenai Intertie will be evaluated with the project in service. Cases will be created at various transfer levels along the interties and simulations will be run to assess the response of the system. The transfer will then be increased until the limit is reached, determined by the first condition that exhibits an unacceptable response as determined by the AKTPL-001 standard. b. The impact on the under -frequency response of the system due to generation trip events will be evaluated. It is expected that the addition of the project will displace conventional generation and thereby reduce the spinning inertia of the system_ This is expected to impact the frequency response of the system and impact the load shedding characteristics of the system. This task will evaluate the impact on the under -frequency response and will assess the ability of energy storage options to improve the response. Cases will be constructed using the current practices of the Railbelt in terms of the amount of primary frequency response carried across the system. Sensitivity cases will be run as needed to determine the additional primary frequency response that must be committed to restore the system response to level that meets the criteria in the AKTPL-001 standard. c. Sensitivity cases will be run to evaluate the benefit and sizing of additional energy storage systems to improve the system response especially during under -frequency conditions. The goal will be to restore the system response to point reach is equivalent to the conditions before the addition of the project. Any sensitivities associated with the location of proposed energy storage (on -site or co -located with other proposed CEA BESS's) will be determined. SEPTEMBER 12, 2022 PAGE 2OF5 WWW.EPSINC.COM 13 DocuSign Envelope ID: C6E8241A-8A7D-4C28-8A39-E8401A1270AA Little Mount Susitna Study Payment Agreement CEA I ALASKA RENEWABLES -INTERCONNECTION AND SYSTEM IMPACT STUDY -PROPOSAL -REV 2 5. Short Circuit Impact and Breaker Ratings a. This task will determine the expected short circuit currents for system faults with the project in service and displacing conventional generation. Breaker sizing will be evaluated based on maximum expected fault current conditions. b. The impact on system voltage with the project in place will be determined, both for steady state conditions and during fault conditions. The protective settings for nearby transmission line relays will be evaluated to ensure proper coordination of the protection schemes_ It is important to note that this task does not include a detailed electro-magnetic transient (EMT) study of the project inverters performance during faulted conditions as this Is outside the scope of this study. 6. Provide recommendations and document results. a. A Draft report shall be prepared and provided to CEA for review and comment. Based on the extensive scope of this study, we anticipate numerous discussions with CEA during process to keep the study on track and minimize any surprises in terms of results and recommendations. b. After review by CEA, a final report shall be prepared and provided to CEA. Assumptions Regulating Requirements CEA has stated that the project cannot depend on CEA regulating reserves for mitigating the impact of variability in the project output. This assumption has a significant impact on the required facilities at the project. We will assume that the project will require sufficient energy storage capacity to effectively regulate the output of the plant to keep the plant output from varying outside allowable rate of change limits to be provided by CEA. CEA will need to provide criteria for allowable setpoint changes and the allowable rate of change of project output for regulating purposes such that the project can then design any required energy storage to meet the rate of change requirements. We assume the project facility owner will analyze the variability of the project output based on siting data, wind speed estimates, and geographic diversity and determine the power and energy capacity required to operate the project within the limits agreed to with CEA for real-time operations. This proposal does not include time and cost estimates for determining the energy storage power rating and capacity required to ensure that the output satisfies the CEA regulating requirements. It is our understanding that an evaluation of the regulating requirements will occur in parallel to this study and will inform the assumptions and modeling of this study. • Minimum Generation Requirements The ability of the Railbelt to accept generation from the proposed wind facility may be impacted by minimum conventional generation requirements within the Railbelt. This study will require that CEA work with us to determine the minimum generation constraints including minimum unit commitment constraints for the Railbelt. The minimum generation constraints may be the limiting condition for integration of the wind facility. This includes the impact of limited spinning inertia and limited short circuit capacity. This study will rely upon CEA for guidance in determining the minimum generation constraints. Dynamic Models Per the interconnection guidelines, the project developer is expected to provide steady state and dynamic models for the facility, including the PSS/e and Aspen models. Use of standard (built-in) inverter models is preferred, and EPS can build the models if all the model parameters are provided. The developer and equipment manufacturer are responsible for ensuring that the models accurately represent the expected behavior of the facility and equipment during transient and short circuit conditions. This includes voltage and frequency ride through conditions and limits. • System Impact of Multiple Renewable Projects and Impact on Cost This proposal has been prepared and priced based on assuming that the project is evaluated without other renewables in place. If multiple projects can be studied in parallel, there can be a reduction in the overall cost of these studies. This assumes that each project does not have to be studied in isolation. This also SEPTEMBER 12, 2022 PAGE 3OF 5 1,V.VW.EPSINC.COP1, 14 DocuSign Envelope ID: C6E8241A-8A7D-4C28-8A39-E84o1A1270AA Little Mount Susitna Study Payment Agreement CEA/ ALASKA RENEWABLES - INTERCONNECTION AND SYSTEM IMPACT STUDY -PROPOSAL -REV 2 means that the overall impact on the system will not be broken down into the impact of each project, except for localized issues. The overall system response, studied primarily in task 4 above, will be evaluated with all new projects in place. Otherwise, no reduction in effort or cost savings is expected. Data Request We request the following data be provided prior to beginning the studies: Data: 1. Expected facility output during different times of the year (maximums and minimums). Models: 1. PSS/e or equivalent transient stability model for the inverters / wind turbines. This includes a description of the expected operating modes (frequency droop, volt/var droop, etc.). The model must accurately include the low voltage ride through and frequency ride through characteristics of the plant, along with supporting documentation. 2. PSS/e model for ancillary equipment (reactive compensation, energy storage systems, etc.). This includes the project step-up transformer and any equivalent collector system models_ 3. Short circuit model in ASPEN. This model must also provide accurate short circuit contributions and ride through modeling for low voltage conditions. We will also require the current ASPEN model for CEA. Drawings: 1. One -line and three -line drawings. 2. Diagram depicting point of interconnect/site overview. Datasheets (nameplates and manufacture data): 1. Inverter/turbine datasheet/manufacture data. 2. Any other known devices (transformers, breakers, protection elements, voltage controls, etc.). Cost Estimate The following table lists the major tasks to be performed and the estimated cost for each major task. 9 Task Cost 1 Facility Modeling $ 20,000.00 2 Interconnection & Power Flows $ 30,000.00 3 Interconnection Stability $ 40,000.00 4 Transient Stability - System Impact $ 50.000.00 5 Short Circuit & Breaker Ratings $ 20,000.00 6 Recommendations and Reports $ 20,000.00 Totals $ 180,000.00 The study cost estimate is a time and materials, not to exceed amount of $180,000.00. This study can be Completed within 5 months assuming no delays in obtaining the required data, models, drawings, and descriptions for the project_ CEA is required to provide the transmission planning criteria and assist in determining the criteria for evaluating the minimum generation requirements as described above. All required changes to the scope and costs will be discussed with and approved by CEA prior to incurring any such costs. Impact of MuRiplo Renewable Protects on the CEA System As discussed previously, there are other large renewable projects being proposed for the CEA system. Portions of the scope of work should be studied with all proposed projects assumed to be in service. The cost estimate for this study has been developed assuming that only one project is the focus of the study. If each proposed project is studied in isolation, this cost estimate reflects the cost of each study. If multiple projects can be studied simultaneously, a reduction in the overall cost of the combined studies can be SE PTEMBER 12, 2022 PAGE 4 OF 5 W W W. EPSINC.C,OM 15 DocuSign Envelope ID: C6E8241A-8A7D-4C28-8A39-E8401A1270AA Little Mount Susitna Study Payment Agreement CEA i ALASKA RENEWABLES - INTERCONNECTION AND SYSTEM IMPACT STUDY -PROPOSAL -REV 2 realized. We propose to split the cost of any tasks that can be combined and studied for both projects simultaneously. The shared tasks include portions of tasks 2 and 3, and all of task 4. Personnel This work will primarily be performed in our Redmond, WA office by Senior Power Systems Engineer, Rich Meier, P.E. and Principal Engineer, Dr. James Cote, P.E. Other studies staff in Redmond may be utilized as needed, especially to reduce the study costs. If you have any questions, please feel free to give me a call at 425-296-5411, or Rich Meier at 425-243- 3259. Sincerely, li�� fV4�-. James W. Cote, Jr_, Ph.D., P_E_ Principal Engineer Electric Power Systems Inc_ I[01