Solar and wind battery storage technologies are being developed and brought to market to address the need for power demand during peak hours and to act as a back-up power source for wind and solar ‘off’ times. The long-lasting battery technologies are now being tested in four states by two different start-ups; Aquion Energy and Ambri. One start-up is testing a design to enable homeowners and business to draw upon the battery during peak hours and thus, lower their costs. The second start-ups’ technology is designed to plug directly into the power grid to offset peak demand and reduce strain on the grid as a whole.