AES Energy Storage Angamos Battery Energy Storage System (BESS)

Name of Project:
AES Energy Storage Angamos Battery Energy Storage System (BESS)
Mejillones, Chile  
Grid Stabilization  
AES Gener, a subsidiary of the AES Corporation, is the second-largest generator of electricity in Chile with more than 4,500MW of generation capacity installed primarily in Chile with some located in Argentina and Colombia  
AES Energy Storage, a subsidiary of AES Corporation, is the owner-operator of advanced storage projects that provide emissions-free capacity to improve the performance and reliability of today’s power grid.  
A123 Systems  
Operational since December 2011 


In 2011, AES Gener, in cooperation with its subsidiary Empresa Eléctrica Angamos, completed construction on a 544MW thermal power plant in the town of Mejillones in Northern Chile. The plant provides electricity to this important mining region. To ensure grid reliability against transmission or generation losses, power generators in the region each hold back capacity to meet system response for primary and secondary reserves. Based on the success of their Los Andes Battery energy Storage System (BESS) project, AES Gener and AES energy Storage developed a battery based storage system to meet the critical grid reliability needs of the Sistema Interconnectado del Norte Grande, or SING, the independent System operator of the Northern Chilean electric grid.


For the Angamos project, AES Gener and AES Energy Storage developed a 20MW/5MWh containerized grid energy storage solution to perform reserve capacity functions for grid support. A123 Systems supplied the storage system and provided system integration of the power electronics from ABB. The storage unit continuously monitors the condition of the power system and responds immediately with up to 20MW to any significant frequency deviations (i.e., the loss of a generator or transmission line). the system supplies sufficient immediate power response to help maintain the grid until the fault can be cleared or other resources can be re-dispatched.


By meeting the reserve obligations of the plant with this energy storage plant, AES Gener was able to increase the power generation available to its customers from its thermal plant by 20MW, thus generating significant additional revenue. The storage unit has been successfully performing the critical reserve capacity function required since commissioning in December 2011. Reports by CDEC-SING confirm the unit provides very fast response and is among the most reliable available for grid contingency events. the speed of response also provides for quicker restoration and stability of the system compared to reserve capacity provided by thermal plants. The energy storage plant has no significant emissions and allows the AES thermal plant to run more smoothly and efficiently, reducing the concentration of it’s emissions. this energy storage plant was commissioned in December 2011 and is the second such plant installed by aeS gener. in 2012, the edison electric institute recognized aeS angamos as the international edison award winner of the Year.

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