The Mejillones AES Angamos BESS is a 20,000kW energy storage project located in Mejillones, Antofagasta, Chile.

The electro-chemical battery energy storage project uses lithium-ion as its storage technology. The project was commissioned in 2012.


The Mejillones AES Angamos BESS was developed by AES Energy Storage. The project is owned by AES Gener (100 %), a subsidiary of The AES .

The key applications of the project are electric supply reserve capacity – spinning and frequency regulation.

Contractors involved

A123 Systems, AES Energy Storage and AES Gener have delivered the battery energy storage project.

Additional information

This project will utilize 20 MW of A123 lithium-ion batteries to supply a flexible and scalable emissions-free reserve capacity installation for AES Gener.
The energy storage system is capable of providing up to 20 MW of power nearly instantaneously. This output is designed to be maintained for 15 minutes at full power.

About AES Energy Storage

AES Energy Storage LLC (AES Energy), a subsidiary of The AES Corp, is an energy service provider that offers commercial energy storage solutions. The company provides operation and maintenance, and planning and deployment services. Its planning and deployment services include facilities design and engineering, site development and preparation, geotechnical evaluation and permitting, interconnection engineering, bidding management, procurement and construction, critical system commissioning, facility commissioning, and project planning. AES Energy owns and operates power plants in the US. The company caters its services to the utilities, power markets, independent power producers, and renewable developers. AES Energy is headquartered in Arlington, Virginia, the US.


All publicly-announced energy storage projects included in this analysis are drawn from GlobalData’s Power IC. The information regarding the projects are sourced through secondary information sources such as country specific power players, company news and reports, statistical organisations, regulatory body, government planning reports and their publications and is further validated through primary from various stakeholders such as power utility companies, consultants, energy associations of respective countries, government bodies and professionals from leading players in the power sector.