The United States has now added the capacity to store a billion watts of power for one hour and it may double that total by the end of this year. According to the firm GTM Research, the energy storage industry – previously nearly invisible – is undergoing rapid growth. Much of the growth has been in homes with products like the Tesla Powerwall but has also been on the scale of the electric grid, where power companies can use storage to control when to deploy excess electricity generated from renewable sources such as solar power.
