A 500-megawatt (MW) battery that NextEra Energy has proposed in Livingston Parish, Louisiana, is being planned around one large customer that no one has named. The grid filing describes a commercial load needing 330 to 360 MW of capacity. It does not identify that customer, and it says nothing about the data center neighbors have been speculating about.

The project, Steamboat Energy Storage, is one of 15 proposals in the fifth cycle of the Midcontinent Independent System Operator's (MISO) Expedited Resource Addition Study (ERAS), which the grid operator announced September 8. ERAS fast-tracks interconnection studies for projects MISO considers critical to reliability, and the program is capped at 68 projects before it sunsets in 2027. Being studied is not the same as being cleared to build.

What the Grid Filing Shows

MISO's list of ERAS requests names NextEra Energy Capital Holdings as the applicant for a 500 MW, four-hour battery, with Entergy Louisiana as transmission owner and a requested in-service date of June 30, 2028. It would connect to Entergy's Willow Glen to Coly 500-kilovolt line. The filing places that point inside the Amite South load pocket, an area it describes as constrained for both transmission and generation.

The battery would serve a portion of the customer's long-term resource adequacy needs, meaning the capacity that must be lined up to cover peak demand. By the filing's own wording, Steamboat is one piece of that customer's supply and not the whole of it.

Four Hours Is Not All Day

A battery's megawatt rating says how fast it can deliver power, while its duration says how long it can keep going before it needs to recharge. A four-hour system can carry evening peaks or a run of tight hours. A facility running around the clock still needs other supply for the rest of the day, plus electricity to refill the battery. The filing leaves open where that power would come from and what upgrades a constrained part of the grid would need, questions Louisiana already faces as data center demand puts energy costs in the spotlight.

The Data Center Question

Local attention has settled on a roughly 690-acre site off Buddy Ellis Road. Its developer first planned homes there, and the parish zoning commission approved an industrial rezoning in November 2025. On October 1, Parish President Randy Delatte said he expects a data facility in the parish within five to 10 years. He did not tie it to Steamboat, and he said he had heard the battery might be built in neighboring Ascension Parish with power sent to Livingston, so even the final site is unsettled.

Residents have raised concerns about water use, noise and property values. None of those can be weighed properly until a tenant and a design are public, and large projects tend to find that power, water and permits arrive as one constraint.

For companies weighing sites in the region, the filing is another sign that industrial users are competing with data centers for megawatts. The next markers are MISO's study results for this cycle, any state or local approvals, and disclosure of who the customer is and how it plans to cover the hours the battery cannot.