The United States is at the tip of the iceberg when it comes to energy storage innovation. Although the sector has made strong advances in recent years, we are just at the beginning of a wave of technological innovation and implementation. According to the global research firm IHS, the U.S. energy storage market will grow to 1.7 gigawatts in 2017 and should hit 2.5 GW by 2020. This impressive growth is in part due to the rapid expansion of distributed solar and supportive legislation set in place in the strongest U.S. PV market — California.