Energy storage isn’t as sexy as solar projects that offer opportunities to cut ribbons on shiny futuristic technology. Nor does it attract the billions in federal loan guarantees and incentives awarded to wind farms and photovoltaic power plants.

But utilities and the government are increasingly recognizing that energy storage systems  are crucial to integrating intermittent renewable energy projects into the smart grid.

Hence the United States Department of Energy’s finalization last week of a $17.1 million grant to utility AES to build a 20 megawatt lithium ion battery storage system using A123 Systems’ technology.

The battery packs will be installed at an AES facility in Johnson City, N.Y., and used to smooth out fluctuations in the power grid. Rather than burn fossil fuels to balance supply and demand, renewable energy from wind, solar or other renewable sources can be stored in the battery systems and released when needed.

That could reduce carbon emissions from so-called frequency regulation by 70 percent, according to the Energy Department.