North Kohala Energy Storage RFP Questions & Answers

The microgrid being proposed is intended to be able to operate without any conventional synchronous generation resources as indicated in the microgrid single line diagram. The Microgrid BESS resource sought for procurement in this RFP is expected to operate as a Grid Forming resource to provide adequate power quality in the microgrid when islanded in the absence of any conventional synchronous generation. The Grid Forming function of the BESS Microgrid resource inverters is expected to allow distributed PV (assuming this is the DPV abbreviation) to operate within the microgrid when islanding under the same customer use profile as if grid connected.

Yes, the microgrid will be maintained to provide power during planned and unplanned outages for at least the 10 year term of the Energy Storage Services Agreement.

The microgrid has been sized to be able to support islanded operation during average weekday loading conditions between the hours of 6 am and 4 pm, to facilitate 1 hour transitions to and from islanding mode at the beginning and conclusion of an 8 hour work day on the 3300 line. Loading conditions and BESS state of charge prior to any unplanned outages of the 3300 line will determine the exact duration the BESS will be able to sustain an unplanned microgrid. Given this use case and the ability to monitor the BESS and loading during islanded operation, the need to restore the line sooner than planned during planned work can be anticipated and line work can be abbreviated to ensure reliability is retained on days where loading may be higher than average. Further, this same monitoring of BESS SOC during unplanned outages that require microgrid islanded operations can be applied to forecast the desired timing of temporary repairs if necessary to restore the grid connection and BESS charging such that permanent repairs can be made upon restoration of the BESS capacity to support the permanent repair work.

This will be one of the key items to be investigated during the detailed interconnection requirements study (IRS) to be conducted upon selection of a proposal. The bidder will be expected to provide adequate model(s) that represents the actual performance of their BESS microgrid resource such that the IRS can determine adequate operation of the resource when islanded and grid connected. The bidder is expected to have the technical support of said model(s) to be able to ensure adjustable parameters are tuned and set appropriately for both grid connected and islanded operation. The modeling requirement as part of the proposal response is expected to inform our evaluation of each bidders modeling capability and ability to support the required modeling to make this assessment. If any additional supplemental equipment is found to be required to allow for this operation as a result of the IRS, the cost of such equipment will be expected to be the Company’s cost.

Yes. See response to 4 above. The modeling is expected to be a collaborative effort between the bidder and Hawaiian Electric to try to achieve the desired results in modeling and eventually in operations.

The entire BESS SOC is expected to be reserved for the back-up power reliability service to the microgrid area for all unplanned outages of the line even after the line upgrade. Any other grid services are not expected to compete for this SOC. The duration of an unplanned outage at night that the resource can support will depend on loading conditions and BESS state of charge prior to the unplanned outage, but is expected to be able to sustain several hours for all loading conditions and with the intent to retain the full SOC of the BESS for unplanned events.

Please see Attachment T (Capacity Ratio and RTE Ratio) of the Draft ESSA (Appendix L of the Draft RFP) for the Company’s preferred methods for validating the RTE Performance Level. As outlined, the RTE Performance Level is expected to consider inverter efficiency and all ancillary power required for the BESS to operate (including any HVAC loading) in normal operations while actively charging or discharging, but not while in a “standby” state. Given the desired operation of this resource to be in “standby” for a large portion of its operation, the energy the resource consumes while in “standby” is not expected to effect the RTE Performance Level but the energy would be billed to the Seller at the appropriate tariff rate to ensure the BESS SOC is retained during extended periods of “standby” in preparation for the next unplanned or planned operation of the microgrid.

The microgrid and BESS solution was extensively vetted by stakeholders in the North Kohala community. Further, the technical requirements of the BESS solution have been developed in collaboration with the experienced consultation of Entura and were done in such a way to agnostically interface with the envisioned microgrid controller. Hawaiian Electric plans to utilize a competitive bidding process for the microgrid portion of the project. Details of further stakeholder engagement for the microgrid portion of this project, which include the islanding controller and the microgrid controller, have not yet been finalized, but will likely begin once the manufacturer for the equipment has been chosen and prior to filing the application for this work with the PUC.

Specifications and technical requirements for the microgrid portion of the project remain preliminary in preparation for the selection of a specific BESS resource and therefore have not yet been finalized. The technical requirements and specifications for the microgrid portion of the project will be designed to work in concert with the specific BESS resource selected. Preliminary design considerations of the microgrid portion of the project are currently coordinated with the functional requirements included in the BESS RFP and the Company’s existing SCADA system. The specific design and specification may be modified depending on the specific BESS resource selected and how its capabilities are to be monitored and controlled by the microgrid portion of the project as well as the microgrid’s interface to existing Company SCADA.

These components will be procured through a competitive bidding process and will be owned and operated by Hawaiian Electric.

The current projection is to file the application to the PUC for the microgrid portion of the project in December 2022, concurrent with filing of executed ESSA. Procurement would occur upon favorable decision from the PUC.

Per Section 1.5.2 of the RFP, RFP questions and Hawaiian Electric responses to them may be posted on www.hawaiianelectric.com/NorthKohalaEnergyStorageRFP.

There is no Request For Information (RFI) scheduled after the RFP is released. Please reference Chapter 3, Table 1 of the RFP for the RFP Schedule. However, prospective Proposers may submit questions to Hawaiian Electric as set forth in Section 1.5.2 of the RFP.

Per Section 1.9.1 of the RFP, the RFP is following the requirements and procedures set forth in the Competitive Bidding Framework (CBF) that governs competitive bidding as a mechanism for acquiring or building new energy generation and/or system resources in Hawaii. The CBF includes a provision that states, in the event that the utility is seeking to advance a proposal, that the utility shall submit its self-build proposal one day in advance of receipt of other bids.

Hawaiian Electric is using Power Advocate as the Electronic Procurement Platform. Power Advocate will be the solution receiving bids from Proposers. Hawaiian Electric will not have access to any documents submitted by Proposers until after the IPP and Affiliate Proposal Due Date showing in RFP Section 3, Table 1.

Each Hawaiian Electric employee and consultant actively participating in the RFP, be it on the RFP Team, Hawaiian Electric Proposal Team, Shared Resource or Unassigned Company Resource, must sign the Code of Conduct Acknowledgement Form. By doing so, each employee is committing to abide by the RFP Code of Conduct and the accompanying Procedures Manual. These documents outline the policies and procedures under which the competitive bidding process will be undertaken to ensure that the RFP process is fair and unbiased, that all Proposers have access to the same information so that no proposer has an unfair advantage, and that the Hawaiian Electric and/or affiliate options do not have any unfair competitive advantage or enjoy under preference over other bids.

The CBF allows for affiliates of Hawaiian Electric to submit proposal(s) in response to a RFP. In addition to the above-mentioned Code of Conduct and Procedures manual, affiliate proposals are subject to any Affiliate Transaction Requirements issued by the PUC as noted in Section 1.9.1 of the RFP.

Section 1.4 of the RFP discusses the role of the Independent Observer (IO). The IO will monitor all phases of the RFP, including but not limited to, the evaluation and selection of Proposals, communications between Hawaiian Electric and all Proposers, and Hawaiian Electric’s adherence to the Code of Conduct and Procedures Manual to ensure a fair and unbiased process.

Per Section 1.2.5 of the RFP, the Project selected through this RFP shall use the ESSA. The term of the PPA/ESSA will be 10 years.

Hawaiian Electric does not foresee problems with a Company owned and operated controller and 3^rd party owned and operated BESS. The Company believes the draft RFP and ESSA requirements for the BESS as provided allow for the BESS to work with any commercially available controller implemented as a microgrid controller to provide the reliability services envisioned for the North Kohala area. If a stakeholder has a specific concern with a requirement or specification that is not currently included in the draft RFP and ESSA documents that would be counter to this understanding, please provide the specific concern for the Company to address.

The 98% availability is directly related to the BESS resource availability and all that is required from the Facility to ensure the BESS is made available at its Rated Active Power Capacity. The controller’s availability is not to have any impact on the BESS availability contractually and would solely be the responsibility of the Company to ensure it is available and functioning as designed. The Company incentive to ensure controller capability and availability is directly influenced by the impact of such a failure to perform on the Company’s reliability statistics that this project works to directly address. The BESS is only responsible for its own availability and not factors beyond its point of interconnection that may impact its ability to perform.

Hawaiian Electric is not open to an option where a 3rd party provides both the controller and BESS. Per Chapter 1, 3^rd paragraph, the RFP is to procure a single BESS Project only.

Specifications and technical requirements for the microgrid portion of the project remain preliminary in preparation for the selection of a specific BESS resource and therefore have not yet been finalized. The technical requirements and specifications for the microgrid portion of the project will be designed to work in concert with the specific BESS resource selected. Preliminary design considerations of the microgrid portion of the project are currently coordinated with the functional requirements included in the BESS RFP and the Company’s existing SCADA system. The specific design and specification may be modified depending on the specific BESS resource selected and how its capabilities are to be monitored and controlled by the microgrid portion of the project as well as the microgrid’s interface to existing Company SCADA. Also reference Q&A 17.

Please reference the following link for Hawaiian Electric affiliates.

Hawaiian Electric is unable to provide a SOW without costs. However, the Company is able to provide some information on the 2^nd transmission line alternative. For example, the 2^nd transmission line alternative includes approximately 14 miles of new 34.5kV sub-transmission line through an undeveloped corridor, a new 69-34.5kV unit substation, and approximately 2.5 miles of new 69kV line to separate the existing 7300 Line 69kV circuit.

The Phase I Environmental Site Assessment is now available. A copy will be made available upon request and execution of the Mutual Confidentiality and Non-Disclosure Agreement, available as Appendix E of the North Kohala Draft RFP.

Proposers should not need/expect to use space or existing facilities in the existing Hawi Substation. The high voltage demarcation will be at the 34.5kV disconnect switch at the new BESS site per the SLD shown in Attachment 1 of Appendix H of the RFP. The signals needed between the Company and Seller will be through a dedicated demarcation cabinet located at the new BESS Site. Work at Hawi Substation to prepare for the BESS interconnection is the responsibility of the Company and will be done as a separate system project per Section 1.1 of Appendix O of the RFP.

Yes, the price score together with the non-price score totals 1,000 points. The Proposal with the highest total non-price score will receive 600 points, and all other Proposals will receive points equal to the Proposal’s score divided by the top score, multiplied by 600. This reference in Section 4.4.2 will be corrected in the final version of the RFP filed with the PUC.

The Capacity Ratio calculation in provided in Attachment T should read as follows: Capacity Ratio = 100% × (Measured Actual Energy Capacity ÷ PLREC). This calculation will be corrected in the final version of the RFP filed with the PUC.

The referenced portion of Section 4.5 of the draft ESSA should state “two-tenths of one percent (0.002)”. This reference will be corrected in the final version of the ESSA filed with the PUC.

Please note that as provided in Appendix F of the Draft RFP, any drawings, reports or any other information or data relating to the Akoni Pule Site (“Site Information”) are being furnished for the Proposer’s convenience only and the Company assumes no responsibility whatsoever in respect to the sufficiency or accuracy of such Site Information or of the interpretation thereof, and there is no guaranty, either expressed or implied, that the conditions indicated are representative of those existing throughout the Akoni Pule Site. In addition, no assurance is given that conditions found at the time of any surface or subsurface explorations will be the conditions that prevail at the time of construction at the Akoni Pule Site. The Proposer shall be solely responsible for all assumptions, deductions, or conclusions the Proposer may make or derive from the information furnished. Making such information available to the Proposer is not to be construed in any way as a waiver of the Proposer’s responsibility to examine the Request for Proposals and the Akoni Pule Site. Proposer must satisfy itself through its own investigation as to conditions to be encountered at the Akoni Pule Site.

To Hawaiian Electric’s knowledge, there are no existing underground utilities at the Site.

The Company is not updating the contents of the model review at this time.

The date in Section 11.4(a) should be March 18, 2026. This revised outside date takes into consideration the September 19, 2025 GCOD provided in the final RFP. If you are submitting proposed modifications in a Microsoft Word red-line version of the ESSA, you may revise Section 11.4(a) consistent with this correction.

Please note that Hawaiian Electric does not and is not providing tax advice. This response is for informational purposes only and none of the information herein should be construed as, nor is intended to be a substitute for, tax, legal, or accounting advice on this or any matter. You should consult your own tax, legal, and accounting advisors before pursuing any transaction or other course of action.

If a project will be pursing the investment tax credit (ITC), it should indicate the deadlines by which certain conditions need to be met (construction, procurement, etc.) so that the ITC can be safe harbored. As noted in Section 4.4.2 of the draft RFP, projects should, at a minimum demonstrate how they plan to capture any ITC safe harbor, including the identification of risks and schedule assumptions. Further, proposals should include a Gantt chart which, among other things, demonstrates achievement of any ITC safe harbor, if applicable. This Gantt chart should include task durations and dependencies, identify tasks that will be fast tracked, and identify slack time and contingencies.

Pursuant to Section 11.4(c) of the ESSA, if the Company does not timely fulfill its obligations, Seller would be entitled to an extension of the applicable Guaranteed Project Milestone Date “equal to the duration of the period of delay directly caused by such failure in Company’s timely performance” (noting, however, that such extension is only available if Seller has timely satisfied its Seller’s Conditions Precedent).

Pursuant to Section 1.2.10 of the RFP, the selected Proposer will be responsible for all Project costs throughout the term of the ESSA, including among other things, the operations and maintenance of the Project. Section 2.1 of the ESSA further provides that Seller is responsible for the design, furnishing, installation, operation and maintenance of the Facility in accordance all applicable laws, permits/gov’t approvals, GEOPS and the terms of the ESSA.

No such information is available at this time. However, topographical maps are available in the Phase 1 Environmental Site Assessment. Further, aerial footage and photos will be made available in late May. These materials available upon request and execution of the Mutual Confidentiality and Non-Disclosure Agreement, available as Appendix E of the North Kohala Draft RFP).

Technical and equipment requirements may be found in the RFP and ESSA. Proposers should review such documents to ensure that the equipment selected can meet or exceed the required performance standards. Please see Section 2.1 of the RFP and Section 3, Attachment B of the ESSA for further detail.

As noted in Section 2.1 of the RFP, “the functionality and characteristics of the storage must be maintained throughout the term of the ESSA. To be clear, Proposers may not propose any energy storage degradation below the Performance Levels for either capacity or efficiency in their Proposals. Ensuring that there is no degradation in storage capacity or efficiency over the term of the ESSA can be accomplished in a number of ways, including overbuilding or pricing in replacement components. The particular manner in which this requirement is achieved is ultimately up to the Proposer to include in its Proposal.”

The Company does not have any generic models or parameters to share. If a Proposer has experience with implementing microgrid controllers or has a generic microgrid controller model, they may choose to include that.

As noted in Section 2.10.1 of Appendix B of the RFP, required diagrams must be approved by a Professional Electrical Engineer registered in the State of Hawaii, indicated by the presence of the Engineer’s Professional seal on all drawings and documents.

The versions listed in the inquiry refer to the version of Electranix’s Technical Memo (the latest version of their memo is v12). Hawaiian Electric currently uses PSCAD v4.6.

The PSSE models should be submitted in all three versions: v33, v34, and v35.

As set forth in Section 5.1 of the RFP and Section 2.10.1.1 of Appendix B, both single and three line diagrams are required.

No, as the scope of the RFP specifies that the term of the ESSA will be 10 years (See Section 1.2.5 of the RFP).

The Company would prefer pad-mounted metering and breakers.

Question 41 has been modified for clarity: “Will any high global warming potential gases (such as sulfur hexafluoride (SF6) or hydrofluorocarbons (HFCs)) be used during operation (such as in switchgears, circuit breakers or fire suppression systems)? If yes, please describe the type and expected annual quantities used, and expected leakage or release rate during operation and end of life.”

Seller’s ability to declare Commercial Operations is not dependent on the microgrid controller. If the requisite testing has been completed (e.g., AT and CSAT), the modeling requirements have been met, the capacity and RTE metrics have been demonstrated and Seller has delivered notice that it is ready to commence operations, Seller can declare, and the initial term will commence.