Origis starts building solar-plus-storage projects in Mississippi with Mitsubishi Power BESS

By Will Norman, Cameron Murray
October 12, 2023
LinkedIn
Twitter
Reddit
Facebook
Email

Developer Origis Energy has started building three solar-plus-storage projects in Mississippi, US, with battery energy storage systems (BESS) totalling 150MW supplied by Mitsubishi Power Americas.

The projects are co-owned by the Tennessee Valley Authority (TVA), a Knoxville-headquartered power utility with which Origis has signed power purchase agreements (PPAs) for the planned capacity. Origis will develop, construct and operate the plants.

The first project expected to reach commercial operations is the 150MW/50MW Golden Triangle II solar-plus-storage project, which is forecast to be online in Spring 2024. Golden Triangle I, a 200MW/50MW site is expected online in Summer 2024; both projects are in Lowndes County. The third project – ‘Optimist’ –  is a 200MW/50MW solar-plus-storage site in Clay County expected online in mid-2025.

Origis said that the projects represent the largest battery storage portfolio and the largest under-construction solar portfolio in Mississippi.

This article requires Premium SubscriptionBasic (FREE) Subscription

Try Premium for just $1

  • Full premium access for the first month at only $1
  • Converts to an annual rate after 30 days unless cancelled
  • Cancel anytime during the trial period

Premium Benefits

  • Expert industry analysis and interviews
  • Digital access to PV Tech Power journal
  • Exclusive event discounts

Or get the full Premium subscription right away

Or continue reading this article for free

Around 1.5 million solar modules will be deployed across the sites, with construction support provided by REC. Mitsubishi Power Americas will supply the battery energy storage systems (BESS).

They are most likely the same three totalling 150MW/600MWh that Mitsubishi Power Americas announced it was providing for Origis for projects in the “Southeast US”, back in December last year, reported by Energy-Storage.news at the time.

They will utilise the firm’s Emerald solution, a lithium iron phosphate (LFP) based BESS product with up to six hours’ duration. They will also utilise Mitsubishi Power’s Emerald Integrated Plant Controller, its energy management system (EMS), and its Supervisory Control and Data Acquisition (SCADA) system to control the BESS.

Energy-Storage.news interviewed Mitsubishi Power Americas’ senior VP energy storage Thomas Cornell last year, while its VP business development for the division Mike McManus recently told us the firm was “enthusiastic” about the potential of domesticating production to capture the 10% bonus domestic content adder to the investment tax credit (ITC).

To see the original version of this article go to PV Tech.

24 March 2026
Dallas, Texas
The Energy Storage Summit USA is the only place where you are guaranteed to meet all the most important investors, developers, IPPs, RTOs and ISOs, policymakers, utilities, energy buyers, service providers, consultancies and technology providers in one room, to ensure that your deals get done as efficiently as possible. Book your ticket today to join us in 2026!

Read Next

December 5, 2025
Developer BrightNight and independent power producer (IPP) Cordelio Power have announced financial close of the 200MW/800MWh Greenwater battery energy storage system (BESS) in Washington state, US.
December 4, 2025
RWE Clean Energy has commissioned the Stoneridge Solar PV project in Texas, adding 200MW of solar PV and 100MW/200MWh BESS to its operational portfolio.
Premium
December 4, 2025
A subsidiary of utility Northern Indiana Public Service Company (NIPSCO) has struck a deal with Amazon to construct 3GW of new dispatchable capacity, with the aim of serving the tech company’s planned data center expansion.
December 4, 2025
PJM has awarded 23 battery energy storage system (BESS) resources, totalling 2.2GW, with interconnection agreements (IAs) in its first transition cycle (TC1) of the reformed interconnection process.
December 2, 2025
South Carolina public utility company Santee Cooper has applied for a Certificate of Environmental Compatibility and Public Convenience and Neccessity (CECPCN) with the state’s public service commission (PSC), for its 300MW/1,200MWh battery energy storage system (BESS).