Investor-owned utility (IOU) Entergy is seeking regulatory approval from the Arkansas Public Service Commission (PSC) to construct what could become the largest BESS in the southern US State. It will support a data centre from Google.
Entergy outlined its plans for the huge 1.4GWh hybrid BESS early last week, as part of a detailed Certificate of Environmental Compatibility and Public Need (CECPN) application seeking approval to construct and operate the project destined for Arkansas’ Jefferson County.
Alongside its noteworthy size, Entergy drew further interest in the project later on in the week after it submitted additional filings with the state regulator linking the hybrid BESS with one of Google’s hyperscale data centres.
Cypress Solar & BESS
As detailed within the CECPN filings, the Cypress Solar project will pair a 600MW solar facility with a 350MW/1,400MWh lithium-ion based BESS located across approximately 3,000 acres of land east of the Arkansas River near Pastoria.
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The project will connect to the Midcontinent Independent System Operator (MISO) electricity grid via Entergy’s White Bluff 500kV substation.
Initial development of the project has been carried out by Plum Bayou Solar, LLC, which is a business subsidiary that was registered with the Arkansas Secretary of State’s office back in 2021.
According to relevant business entity filings, the subsidiary is owned by Oakland, California-based company Orion Renewables, which has developed the project for Entergy as a self-build resource.
Orion commenced development of the project after recognising an opportunity to utilise existing interconnection rights to Entergy’s White Bluff substation.
After acquiring several thousand acres of land for the project and completing an initial project design study, Orion submitted an unsolicited offer to Entergy in the form of an asset purchase agreement (APA).
The two parties then executed a letter of intent to negotiate and work towards the sale of the project, before successfully entering into the APA. Following an Entergy-administered RFP that took place late last year, the utility negotiated an EPC agreement with Wanzek Construction to carry out site installation on its behalf.
Although the filings state that Wanzek is responsible for providing the BESS units under the EPC deal, specific manufacturers aren’t named. Unlike the BESS, Entergy is responsible for providing the solar modules and has opted for ones manufactured by Canadian Solar.
If all goes to plan, construction is expected to commence during the second quarter of next year ahead of commercial operations, which are currently scheduled for the fourth quarter of 2028.
Google hyperscale data centre
The Cypress Solar project was mentioned throughout a series of heavily redacted filings also submitted with the Arkansas PSC last week, relating to a special rates contract (SRC) between Entergy and Google-owned subsidiary Altitude Capital, LLC.
As outlined within the filings, Entergy is seeking regulatory approval of the contract which will “provide electricity supply to support Google’s establishment of a new, hyperscale data centre in the City of West Memphis in Crittenden County, Arkansas”
It’s long been rumoured that Google was planning to develop one of its hyperscale data centres in West Memphis, with these recent filings confirming the company’s intentions.
Earlier this year, West Memphis City Council negotiated several development agreements with a mysterious business subsidiary, allowing for the construction of a data centre worth up to a staggering US$10 billion.
Although the SRC is wholly redacted, testimony filed with the Arkansas PSC from Entergy’s Vice President of Regulatory Affairs, David Palmer, outlines how the Cypress project ties in with Google’s new data centre.
“The terms of the [SRC] provide for the development of a new, large solar and battery generation resource – Arkansas Cypress Solar,” stated Palmer within his testimony.
Palmer also revealed that as the utility currently doesn’t have the capacity to support Google’s new data centre, “the SRC commits [Entergy] to develop, and Google to financially support through the rates included in the SRC, Cypress Solar to add generation to the Company’s resource portfolio.”
Although the Cypress project will tie into the wider MISO grid, “it will provide energy and capacity to support service to a significant portion of Google’s incremental load,” explained Palmer.
The testimony also reveals that Entergy is developing the Cypress project to follow the in-service date of the data centre “as closely as feasible to meet Google’s needs.”
Last week, Google announced it help fund non-lithium long-duration energy storage (LDES) pilot projects in Arizona in partnership with utility Salt River Project (SRP), demonstrating it sees a clear future need for both short- and long-duration energy storage to support its data centre operations.
