2026-SC-GEN 00007 Published On: 07/22/2026
Question: What are the ranges of expected shortlist MW size? If the limit of contracting is 400MW and there are meant to be reserve projects that continue to invest time and capital into development, it would be helpful to understand a range of expected shortlist sizes in terms of MW.
Answer: Based on the bid scores from the “Step 1” proposal evaluation, top-ranked bids equating to approximately 2.5 times the target quantities of ESSA and UOT are expected to be invited to “Step 2” of the proposal evaluation. If a Reserve List is created, it is expected to be active only during the periods shown below:
2026-SC-GEN 00006 Published On: 07/14/2026
Question: For the 2026 SC Battery RFP: What proposal deliverables are due on the 8/5 RFP deadline (format of bid narrative, technical supporting documentation, etc.)? This is not apparent from the RFP instructions, nor available RFP documents.
Answer: The August 5, 2026 deadline is for submission of complete proposals, including:
The UOT and/or ESSA Bid Input Form(s);
All supporting documents requested in the Bid Input Form(s);
A completed Interconnection Application for the 2026 RFP-specific Resource Solicitation Cluster, submitted through PowerClerk at https://carolinas-annual-cluster.powerclerk.com/MvcAccount/Login;
Payment of the Proposal Fee, Payment of the Interconnection Study Deposit and/or FERC Application Fee, if applicable. Interconnection deposits and bid fees can be paid via wire transfer or through the Interconnection Portal, and wiring instructions are available in PowerClerk as part of the workflow.
The Bid Input Forms will become available at https://www.dukeenergyrfpcarolinas.com/2026-SC-Battery-Documents once the RFP bid window opens on July 15. The RSC interconnection application through PowerClerk will open the same day.
2026-SC-GEN 00005 Published On: 07/14/2026
Question: Question for 2026 SC Battery RFP: Given that BESS assets are typically underwritten and financed on a 20-year useful life, and that there is no merchant off-take option available in this market, would Duke Energy consider accepting bids structured around a 20-year tolling term for the ESSA, rather than the standard term currently contemplated in the RFP/Pro Forma?
Answer: The standard contract term offered to all ESSA participants in this RFP is 15 years (part of Public Service Commission South Carolina approval of RFP Stage 1 Application).
2026-SC-GEN 00004 Published On: 06/25/2026
Question: When can we expect an invite to the 2026 SC BESS RFP pre-bidders conference?
Answer: The Pre-Solicitation Bidders Conference for the SC BESS RFP will be announced in early July. Registered users on this website wlll receive an email notification. The link to register to attend the conference will also become available under the Timeline section of the Home page.
2026-SC-GEN 00003 Published On: 06/09/2026
Question: This question pertains to the 2026 SC Battery RFP. Can a sponsor submit two proposals at the same substation, with one project/POI request under the UOT track, and the second project/POI under the ESSA track?
Answer: The same facility may be offered under both RFP tracks (UOT and ESSA) as long each bid complies with the requirements for the respective track and is the same POI and not a different POI.
2026-SC-GEN 00002 Published On: 05/11/2026
Question: For the 2026 SC Battery RFP are you accepting projects that are located in North Carolina?
Answer: SC Battery RFP projects must be located in South Carolina, please see the DEC DEP 2026 SC Battery Draft RFP Document, Section III (Facility Eligibility Requirements and Proposal Tracks) for details.
2026-SC-GEN 00001 Published On: 05/11/2026
Question: For DEP’s 100 MW BESS procurement (assumed ~50 MW ESSA and ~50 MW UOT), how is the 50% sponsor cap applied? Specifically, is the cap calculated at the total DEP award level (i.e., 50 MW across both ESSA and UOT), or separately within each track (i.e., up to 25 MW in ESSA and 25 MW in UOT)?
Answer: The 2026 SC Battery RFP intends for the 50% market breadth requirement to apply across the procurement total and not per track or per balancing authority area.
2026-SC-DOC 00006 Published On: 07/16/2026
Question: Can you clarify if the Project Evaluation Confidentiality Agreement should be completed by each project entity anticipating submittal?
Answer: We will accept a single Project Evaluation Confidentiality Agreement executed by the project owner(s) versus separate Project Evaluation Confidentiality Agreements from each project LLC.
2026-SC-DOC 00005 Published On: 07/14/2026
Question: Could you please provide the NOIR form? We have not received it and would like to register our projects.
Answer: The Notice of Intent to Respond (NOIR), Confidentiality Agreement, and Bid Input Forms will become available at https://www.dukeenergyrfpcarolinas.com/2026-SC-Battery-Documents once the RFP bid window opens on July 15.
2026-SC-DOC 00004 Published On: 07/14/2026
Question: Would Duke Energy be open to incorporating an asset buyout option after Year 15 of the ESSA term, structured via redline to the current Pro Forma ESSA?
Answer: A buyout option is not a consideration for the ESSA in this RFP. Projects can bid in both the UOT track and the ESSA track, and bidders have a deadline of October 21, 2026, for a project that bid both UOT and ESSA to withdraw only from the ESSA track.
2026-SC-DOC 00003 Published On: 07/13/2026
Question: The Duke RFP materials state that for the ESSA track a developer must have completed a 50MW battery and for the UOT proposal must have "completed or directly managed the completion of the development and preliminary engineering of >50 MWAC or 3x the nameplate capacity of the Proposal, whichever is greater, of battery facilities..." Is failure to meet the full criteria for the relevant track disqualification from the process or a lower score in the experience subcategory?
Answer: The language about the developer experience is part of Section VI.B of the RFP ("NON-ECONOMIC SCORING CRITERIA"). Not meeting the described criteria will not result in disqualification, however may yield a lower score for this part of the proposal evaluation.
2026-SC-DOC 00002 Published On: 07/08/2026
Question: The DEC/DEP Interconnection Cost Estimates provided in the document do not explicitly say that the cost estimates are relevant to the 2026 SC Battery RFP. Can you please confirm that these costs are relevant? Additionally, there is no 230 kV DEC figure given despite applicable 230 kV POIs on the system. Please confirm why this is the case.
Answer: The document header identifies that the interconnection cost estimates posted at https://www.dukeenergyrfpcarolinas.com/2026-SC-Battery-Documents pertain to the 2026 SC Battery RFP.
This document covers standard interconnections, and DEC does not permit single breaker taps to 230 kV lines, which is why the document indicates “N/A” for 230 kV for DEC. Interconnection to an existing Multibreaker Switching Station in DEC is covered by the last row of Table 1.
2026-SC-DOC 00001 Published On: 06/18/2026
Question: In the revised Draft RFP document UOT requirements in Section III.B(a) there was from "...Onsite acoustic survey" to "...onsite acoustic survey schedule". Can you please confirm that the intention is for bidders to have scheduled an onsite acoustic survey but that this does not need to be complete prior to bid submittal?
Answer: This is consistent with the response to 2025-DOC 00012 in the 2025 RFP, which confirms that the applicable bat studies do not need to be performed prior to bid submittal, but are required as part of selling a fully developed project as part of an Asset Transfer proposal. Response to 2025-DOC 00012 is provided for convenience:
For Asset Transfer proposals, as part of selling a fully developed project, the MP must complete a habitat assessment and onsite acoustic survey for all listed and proposed to be listed bat species, as well as any bat species listed or proposed to be listed after the issuance of the RFP. This is included as a condition to close, as part of selling a fully developed project to the Utility. The MP should provide a copy of the both the assessment and survey plan, prior to submittal to applicable agencies. If the MP has completed said surveys, they should include them in their bid submittal, if assessment/surveys have not been completed, Duke will review them as they are provided either in context of the RFP evaluations or within the governing Asset Purchase Agreement.
2026-SC-INT 00009 Published On: 07/24/2026
Question: Duke's "Substation Configuration Guideline for Transmission Inverter Based Interconnections" says that for a greenfield substation for an inverter based resource, the total site capacity within 1 mile must be less than 100 MW. Does that mean that the inverter based resource (like BESS) that wants to tap a line must be less than 100MW? Since the RFP only allows bids in 25MW increments, would the only permissible size for a tap be 25, 50, or 75 MW?
Answer: An inverter based resource must be less than 100 MW to be considered for a single breaker tap interconnection. If an IBR project is 100 MW or greater or the third IBR interconnection on a single transmission circuit, the IBR will be required to connect via multi-breaker switching station (MBSS). Depending on location and configuration, being less than 100 MW does not guarantee that the interconnection will be via a single breaker tap interconnection.
In the 2026 SC Battery RFP document section IV.D. (Proposal Evaluation), during Step 2 when considering risk of Network Upgrade costs and interdependencies, the Companies reserve the option to request some Proposal size flexibility, but such flexibility will only be used if both parties agree. For example, if reducing a 100 MW project to 99 MW would avoid an MBSS, the Companies may ask the party if they would be willing to reduce the project size (however, there may be other reasons an MBSS is required for a site). As noted in the detailed footnote in section IV.D on page 21, the maximum reduction percentage is based on Sections 4.4.1 and 4.4.2 of the Modifications section of the FERC LGIP (decrease only). Also, the sizing change does not have to occur at the end of the RSC Phase 1 study (e.g., Phase 2 RFP Evaluation) if a benefit to the downward size is identified earlier.
2026-SC-INT 00008 Published On: 07/22/2026
Question: At what stage in the process will the evaluation team confirm that the point of interconnection (POI) requested is valid? If the POI validation occurs prior to the Step 1 RFP evaluation, and the POI is not valid and the bidder cannot be cured, will the bid fee be returned?
Answer: The RFP Evaluation team will confirm with the Renewable Integration team that the requested point of interconnection (POI) is valid during the RFP Step 1 evaluation phase and during the RSC pre-Phase 1 Customer Engagement Window, both of which occur after the close of the Cluster Request Window, currently scheduled for August 5.
The Proposal Fee is non-refundable; interconnection deposits are separate from the RFP proposal fees. Step 2 proposal security will not be collected for the RFP if there are issues identified with the POI. If the POI is determined to be invalid during the RSC pre-Phase 1 Customer Engagement Window, the Interconnection Customer will be responsible for and charged its share of the cost allocations incurred during that window. The remaining study deposit and the Commercial Readiness Deposit will be refunded to the Interconnection Customer (see DEC / DEP LGIP Section 3.4.4).
2026-SC-INT 00007 Published On: 07/22/2026
Question: Is there a mechanism to compensate for change in IFC estimates included in the bid price versus the actual IFC in the final accounting register of the project?
Answer: There is no mechanism to compensate for changes from estimated to actual Interconnection Facilities costs. Reference DEC and DEP Standard Interconnection Cost Estimates document for guidance on the Interconnection Facilities cost.
2026-SC-INT 00006 Published On: 07/22/2026
Question: If the COD of the project changes as part of IX study results, will there be an opportunity to adjust the pricing?
Answer: COD changes due to network upgrades identified in RSC Phase 1 interconnection study and any iterations during Step 2 of the evaluation process (see Section VI. D. of the RFP document “Step 2”) would not adjust bid pricing. The Companies may decline a proposal if the Companies determine through Step 2 of the evaluation process that network upgrades or interconnection facilities required to interconnect the facility cannot be constructed in time to achieve COD by December 31, 2031 (see Section II of the RFP document). A Finalist may decline to participate and receive a refund of their Step 2 Proposal Security if the in-service date identified in the Phase 1 RSC report or iterations is after December 31, 2032 (see Section V.B.2. of the RFP document). Network upgrade costs will be considered as part of evaluating cost effectiveness of the portfolio of selected proposals (see Section VI. E.2. of the RFP document).
2026-SC-INT 00005 Published On: 07/13/2026
Question: Is a PSCAD model needed by 8/5/26 for RFP submission? Or it can be provided later?
Answer: PSCAD / PSSE models are required at the time of the interconnection application submission. Sections 7h, 7i and 8h of the Inverter Based Resource Data Request form located on the OASIS site (Duke_Energy_Inverter_Based_Resource_Data_Request_Form_(DEC,DEF,DEP).pdf (oati.com)) provides guidance for inverter and reactive power PSSE modeling.
2026-SC-INT 00004 Published On: 07/08/2026
Question: For 2026 SC Battery RFP, can the study deposit be posted as a Letter of Credit or it needs to be posted as cash?
Answer: The Study Deposit must be posted as cash.
2026-SC-INT 00003 (revised 07/07/2026) Published On: 07/07/2026
Question: We would like to oversize our interconnection request at time of interconnection application over and above the max allowable 100 MW indicated by the RFP. Are we able to do that via the RSC, or do you require a separate interconnection application for the second phase?
Answer: RSC interconnection request amounts must relate to only eligible projects sizes in the 2026 SC Battery RFP document section B(a) for UOT proposals and section B(b) for ESSA proposals and not oversized.
2026-SC-INT 00002 Published On: 06/25/2026
Question: What date will the 2026 Resource Solicitation Cluster (RSC) open?
Answer: The 2026 Resource Solicitation Cluster (RSC) used for the 2026 SC Battery RFP will open July 15, 2026. This date will be updated in 2026 SC Battery RFP Document 11 and posted on or around July 7 with final documents to the RFP website.
2026-SC-INT 00001 Published On: 06/05/2026
Question: As we finalize our site selection and preliminary engineering, we have a question regarding transmission interconnection parameters. Could you please clarify where there are any interconnection restrictions by line voltages? If so, do they apply equally for DEC and DEP?
Answer: Projects must be directly interconnected to the Duke Energy Carolinas (DEC) or Duke Energy Progress (DEP) transmission system. For Utility Ownership Track (UOT) proposals, Preferred Battery Facility GSU Sizing is provided in Document 10, available at https://www.dukeenergyrfpcarolinas.com/2026-SC-Battery-Documents.