The U.S. energy storage market grew 243% in 2015, according to a recent report by GTM Research and the Energy Storage Association (ESA), Washington, D.C. In fact, there was more energy storage capacity deployed in just one quarter of 2015 (112 megawatts) than in 2013 and 2014 combined (106 megawatts), says the report.

 “We can look back at 2015 as the year when energy storage really took off,” said GTM Research Energy Storage Analyst Ravi Manghani in the report's press release.  By 2020, total energy storage capacity is expected to reach 1.7 gigawatts, an eightfold increase from 2015, and will have a $2.5 billion market value.