AES Dominicana announced that it brought online 20 MW of new battery-based energy storage arrays at two sites in the Dominican Republic, which played a role in maintaining grid reliability in September when Hurricanes Irma and Maria struck the island.

The two 10 MW arrays were supplied by AES Energy Storage. Located on sites in the Santo Domingo region, both arrays are providing critical grid reliability services for the island by improving the efficiency and contributing to the stability of the Dominican Republic’s interconnected national electricity system (SENI).

“We are very excited about developing these energy solutions for the benefit of the Dominican Republic, saving millions of dollars in state funds, which can be redirected to more needed areas such as public health, education and security,” said Edwin De Los Santos, President of AES Dominicana.

AES Dominicana is using its Andres and Los Mina DPP Advancion energy storage arrays to provide fast, accurate frequency control to the Dominican grid, balancing second-to-second variations between electricity consumed and produced.

By adding energy storage instead of using existing thermal power plants to maintain frequency, the Dominican grid operator can enable the power plants on the island to run at their most efficient generating level while the battery systems absorb and discharge energy on the grid as needed.

AES Dominicana’s 20 MW of energy storage is providing fast-response, critical reliability services that would otherwise be performed by a traditional thermal power plant three times the size.

In September 2017, the Dominican grid operator put the two energy storage arrays to a critical test: asking AES Dominicana to keep them online and operational to ensure grid reliability as two hurricanes, Irma and Maria, each approached the island. Both energy storage arrays performed more than double the amount of work during the storms as normal, helping keep the Dominican grid operating during category 3 and 4 hurricane conditions, even as nearly 40 and 55 percent of the island’s power plants were forced offline during Hurricanes Irma and Maria, respectively.