INDIANA MUNICIPAL POWER AGENCY
IMPA Pursues Battery Storage Project

While renewable energy adds valuable resources to any utility's energy mix, sources such as wind and solar still run into the problem of intermittency. Wind turbines and solar parks generate electricity when the wind is blowing and the sun is shining, but when utility customers need power 24 hours a day regardless of the weather or time of day, relying on renewables becomes difficult. Battery storage technology promises to help with this issue of intermittency, but the effectiveness of industrial-sized storage is still uncertain because batteries can only fill the gap over short durations, typically four hours. To investigate the future possibilities of battery storage, the Indiana Municipal Power Agency plans to launch a battery storage pilot project at its Richmond 6 Solar Park later this year.

Beginning in 2021, IMPA began planning for a pilot battery storage project at a solar site, originally designing the Richmond 6 solar park with the budding technology in mind. However, the Agency put a pause on pursuing batteries in 2022 when soaring prices of materials such as lithium carbonate made the project uneconomical. Fortunately, as market prices stabilized through 2024, IMPA revived the project and hopes to begin installation of equipment to support the project this fall.

The pause allowed the Agency time to design the battery project to suit IMPA's needs best and to take a closer look at the project's economics. As staff members reconsidered the project during its pause, they decided to expand it beyond what was originally planned. The original battery project was planned on a relatively small scale, and upon reflection, IMPA realized that a larger sized project would provide a more meaningful pilot project. Now, the battery project design is approximately 12 times the original design, able to store 24 megawatt hours of energy. This means that when dispatched, the battery will be able to discharge six MWs of power onto Richmond's distribution system for four hours. Once fully charged, the battery will be able to hold onto that power until needed, providing a beneficial resource to both IMPA and the local utility in Richmond. The larger scale of the project will allow IMPA to truly explore the potential of battery storage technology.

"This test project will help our staff familiarize themselves with the technology while demonstrating the viability and nuances of battery storage for renewable resources," said Chris Sanders, IMPA Vice President of Generation. "If the project meets our expectations, it will add additional dispatchable resources to our generation portfolio and will allow us to shift our load strategically when market prices fluctuate. With the data we collect from this project, we'll determine if incorporating batteries into other solar parks is worthwhile."

IMPA worked closely with Richmond Power and Light (RP&L) to develop the project, ensuring that the battery storage equipment could be accommodated by the local utility's existing infrastructure and plans for the future. RP&L has been a staunch ally of IMPA since becoming a founding member of the Agency in 1983 and was one of the first member communities to welcome an IMPA solar park into its service territory in 2014. Today, the community hosts eight solar parks constructed by IMPA, totaling over 46 MW of solar capacity.

The Agency has also consulted with other not-for-profit power providers who have experience in battery storage projects to maximize the potential for a successful project. Much of the project has been designed in-house to save costs but also give experience to staff members who may work on future battery projects if the positive potential of the technology is confirmed.

"We are always working to balance innovation with cost-effectiveness at IMPA," said Jack Alvey, President and CEO of IMPA. "We invested in small solar park projects back in 2014 to evaluate the cost, constructability, and reliability of renewable energy, and it's paid off in our solar park program, which now provides over 200 MW to our power supply portfolio. Pursuing this battery project, which will deliver economic benefits, is the next step in planning for the energy needs of tomorrow."