AES claims world’s largest battery storage system

AES will install a 40 MW/160 MWh system which is larger than any battery deployed to date. Image: AES Energy Storage

Move over Tesla. On Monday, AES Energy storage announced the completion of a 30 MW battery storage system in Escondido, Southern California. As verified by GTM Research, with a 120 megawatt-hour (MWh) rating this is the largest lithium ion battery storage system in the world by MWh.

And while this system is 50% larger in capacity than Tesla’s much-hyped battery system at Southern California’s Mira Loma substation, it has not received the press coverage that Tesla’s has. But this is not the only battery system that AES has commissioned, as the company also put online a 7.5 MW array in El Cajon. Both systems are based on AES’ Advancion System, which can work with multiple battery technologies.

When a fourth 20 MW project put online by Greensmith last week is added in, this last week has seen the inauguration of 77.5 MW of battery storage in Southern California. This is equivalent to nearly 30% of the entire capacity of energy storage which GTM Research estimates was deployed in the United States in 2016.

San Diego Gas & Electric Company (SDG&E) owns both the Escondido and El Cajon projects, which AES says will allow not only the integration of more renewable energy but a smarter and more reliable grid. Reliability concerns have been high in California following the Aliso Canyon gas leak, which affected fellow utility Southern California Edison’s supply of fuel for plants used to meet peak demand.

As such these arrays will be a large-scale demonstration of the ability of batteries to replace natural gas-fired plants in meeting peak electricity demand.

“While energy storage are still not quite cost competitive with gas peakers across the board, it does provide some attributes that make it more valuable in certain circumstances,” GTM Research Director of Energy Storage Ravi Manghani told pv magazine.

“The Aliso Canyon deployments are best examples of leveraging these storage attributes – speed of deployment of few months vs. years for gas peakers, modularity, and ability to facilitate more renewables on the grid.”


Update: This article was modified at 3:30 PM Eastern Time (U.S.) February 1 to verify that this system is the largest of its kind in the world by MWh, and to include a quote by Ravi Manghani of GTM Research.