Peak Energy has signed an agreement with RWE Americas to pilot a sodium-ion battery energy storage system in eastern Wisconsin, marking what the companies say will be the first deployment of the technology within the Midcontinent Independent System Operator (MISO) electricity market.
The pilot project will test Peak Energy’s passively cooled sodium-ion grid storage system at an RWE laboratory facility. The companies say the technology could significantly reduce the cost of grid-scale energy storage while improving reliability in a region facing rising electricity demand.
Sodium-ion battery chemistry using NFPP
MISO is the regional transmission organisation that coordinates the wholesale electricity market and grid operations across much of the US Midwest and parts of the South, including Wisconsin. It manages the flow of electricity across 15 US states and the Canadian province of Manitoba, covering a population of around 45 million people.
Peak Energy’s system is based on sodium-ion battery chemistry using NFPP (sodium iron phosphate pyrophosphate) cells. According to the company, the batteries can operate safely across a wide temperature range without active cooling, eliminating the need for energy-intensive thermal management systems and reducing maintenance requirements.
The company says the design also reduces “overbuild” – the additional storage capacity typically installed to compensate for battery degradation over time – lowering the lifetime cost of stored electricity by around $70/kWh.
“Energy storage is central to providing dispatchable, reliable energy on demand,” said Peak Energy CEO Landon Mossburg. “Delivering the lowest-cost electron is Peak Energy’s north star, and we’re proud to work with RWE Americas to operate our cost-optimised batteries.”
The MISO region is expected to require substantial new energy storage capacity as electricity demand grows and more intermittent renewable generation is added to the grid.
A recent Aurora Energy Research report estimated that installing 10 GWh of battery storage in the MISO region over the next decade could reduce system costs by as much as $27 billion compared with a baseline scenario.
Photo of the Wisconsin landscape by Ethan Walsweer on Unsplash
