The Tennessee Valley Authority (TVA) on March 16 said that it is requesting proposals to develop 200 MW of renewable energy, with proposals due by April 24.
TVA noted that it procured more than 1,300 MW on behalf of customers through similar requests for proposals (RFPs) in 2018 and 2019. TVA also said that it while it does not have a need for more base-load energy, the utility is investing in renewables in response to customer demand for cleaner energy and economic development opportunities to attract companies with sustainability goals.
According to the RFP, TVA is interested in procuring up to 200 MW of new stand-alone renewable energy resources or renewable energy + battery energy storage systems (BESS), including all the associated environmental attributes, such as renewable energy credits/certificates.
The RFP also noted that all resources must be located in the TVA service territory or delivered to TVA’s interface with neighboring transmission systems. Solar resources must be tracking, TVA said in its RFP, adding that if any proposal is delivered to the TVA interface, it must have all of the cost components included for an all in energy price. TVA said that it reserves the right to vary from that target energy quantity based on evaluation of bids that are received. Any transaction resulting from the RFP will be in the form of a power purchase agreement (PPA), TVA said.
Projects must be commercially operational and providing renewable energy by Sept. 29, 2023, or earlier, as agreed to by both parties, TVA said.
Respondents are requested to submit proposals for a delivery period of 12, 15, and 20 years. TVA also said that respondents with solar generating sites greater than 5 MW are required to utilize central-type inverters rated 500 kVA or higher and are requested to provide a $/MWh adder for 24/7 reactive power support — utilizing inverters that are capable of producing or absorbing reactive power at minimum of 30% of their rating 24/7 including at night.
TVA said that proposals may be submitted in either or both of the following configurations:
- Not configured with energy storage — Where a proposed project is not coupled with energy storage, the maximum output of the project must not exceed the proposed amount as requested in the TVA Interconnection Agreement
- Configured with energy storage — Proposals may contain storage that may be charged during periods when full potential export is not being taken by TVA. The energy storage should be sized to provide sufficient storage capacity equal to the greatest amount of energy to be provided for a continuous four-hour discharge during a four-hour period. TVA would also like to see pricing for a continuous two-hour discharge during a two-hour period in addition to any four-hour proposal. TVA requests 100, 200, or 365 annual cycles, including the ability to discharge two cycles per day for up to 15 days per calendar year. The project must specify either an AC-coupled or a DC-coupled solution, bearing in mind that TVA is seeking the greatest capacity at the least cost. TVA is interested in evaluating various value-added storage options, and so proposals with several configurations and performance/price options are encouraged. Flexibility in charging/discharging periods will be necessary due to uncertainty in demand profiles. The proposed storage may be charged by the renewable facility or through grid charging that would be configured in order to provide the most economic price to TVA
According to the RFP schedule, a pre-bid conference call will be held on March 26; evaluation of the proposals will be held May-June (tentative); proposals will be selected in August (tentative); and the contract execution will be held in September (tentative).