Japanese energy firm Mitsubishi Power has secured a contract from San Diego Gas & Electric (SDG&E) to supply its Emerald storage solutions for four utility-scale battery energy storage system (BESS) projects in the US.

The Elliot, Clairemont, Paradise and Boulevard microgrid BESS projects, with 39MW/180MWh of total capacity, will be linked to the existing infrastructure in San Diego, California.

SDG&E Advanced Clean Technology director Fernando Valero said: “We live in a time when growing threats from climate change and extreme heatwaves can increasingly impact grid reliability.

“By expanding our energy storage portfolio, we are helping our region and critical community facilities become more resilient.”

Under the contract, Mitsubishi Power will deliver an Emerald Integrated Plant Controller, which will serve as an energy management system and a supervisory control and data acquisition system.

The controller ensures that critical public service facilities have power even during peak demand and unexpected power outages.

The projects have been approved by the California Public Utilities Commission and are scheduled to come online next year.

Upon completion, they are expected to bolster grid resiliency, especially during periods of high energy demand in the summer and peak evening hours.

Mitsubishi Power Americas Energy Storage Solutions senior vice-president Tom Cornell said: “SDG&E was an early adopter of battery energy storage in the western US, and it continues to be a leader in deploying energy storage to serve its customers.

“We’re excited to make an impact with SDG&E on these four microgrid projects in addition to the Pala-Gomez Creek energy storage project announced earlier this year.”

In addition, Mitsubishi Power has agreed to support the Emerald storage solutions under a ten-year long-term service agreement.

In June this year, the company agreed to develop four BESS projects in Ireland in partnership with ION Renewables.