California utility claims biggest flow battery deal in the world

A massive 200MW/2GWh long-duration iron flow energy storage system will be installed in the US city of Sacramento in what is expected to be the country’s – and the world’s – largest ever flow battery purchase.

The Sacramento Municipal Utility District (SMUD) says it will purchase a mix of products from leading US manufacturer of long-duration iron flow batteries, ESS.

The ESS iron flow technology is capable of proving up to 12 hours of flexible energy capacity for both commercial and utility-scale energy storage applications.

Boasting zero degradation over 20,000 cycles and an inherently safe design, the ESS iron flow technology is also exceptionally sustainable.

ESS batteries rely on food-grade and earth-abundant iron, salt, and water for the electrolyte. This not only makes the batteries greener, but also more affordable.

A community-led push to net zero

ESS will deliver a mix of its Energy Warehouse and Energy Center long-duration energy storage solutions. ESS Energy Warehouse is a commercial and industrial size system, whereas the ESS Energy Center is designed for utility-scale systems.

These will be integrated with the SMUD electric grid – the United States’ sixth-largest community-owned electricity service provider – beginning in 2023.

SMUD’s 2030 Zero Carbon Plan will prioritise increasing local solar generation to reduce thermal generation. As such, long-duration energy storage will be a vital component of its decarbonisation plans.

“SMUD is striving for a clean energy future that increases grid resiliency, supports under-resourced communities and maximizes local economic development,” said Paul Lau, CEO and general manager of SMUD.

“Long-duration battery technologies move SMUD’s 2030 Zero Carbon Plan forward by expanding our dispatchable renewable energy resources and opening doors to innovation, job training and development opportunities in the green energy sectors.”

Long duration battery storage

With storage integration expected to begin in 2023, the multi-year agreement signed between the two companies will start with the deployment of several megawatts of storage.

Through the remainder of the decade, larger deployments – relying probably on the ESS Energy Center – will ramp up the storage numbers.

When all 200MW/2GWh of storage is operational it will be the equivalent of removing 284,000 metric tonnes of CO2 emissions per year, while providing enough energy to power 60,000 homes for 10 hours.

“SMUD is a pioneering and progressive public utility that puts its words into meaningful action – in particular its pursuit of a decarbonised grid that will build resiliency, enhance job opportunities, and provide benefits for all customers,” said Eric Dresselhuys, CEO of ESS.

“Our agreement will be a critical component of SMUD’s Zero Carbon Plan. We’re pleased to partner with SMUD in realizing their 2030 Plan.”