In an article about the future of Energy Storage, SNL cites AEE's Advanced Energy Now 2016 Market Report. From the article:
In just three years battery storage capacity has grown from about 300 MW in the U.S. to nearly 900 MW, according to data from the Electric Power Research Institute. Revenue from energy storage has grown from $58 million in revenue in 2014 to $734 million in 2015, according to the advocacy group Advanced Energy Economy.
Read the full article here.