The dominant technology proposed for energy storage systems today are lithium ion batteries, the same batteries that power our phones and electronics, but on a larger scale. Lithium ion batteries are well researched and vetted, and are sited in a way to minimize risk of fire and adverse effects. Long duration energy storage systems are being proposed to power the grid for days on end with iron-air makeups that take advantage of the energy released during a rusting process. Mechanical energy storage takes many shapes but involves lifting heavy weights above the ground and releasing them slowly and harvesting the kinetic energy.

Bath County, Virginia is home to the world’s largest battery in the Bath Pumped Storage Station. Water is pumped from a valley reservoir to a mountain top reservoir to store the water’s potential energy. When the energy is needed, the water is released to spin turbines at the lower reservoir, producing 3 Gigawatts of energy at peak output. According to Dominion,  “the world’s most powerful pumped storage generating station quietly balances the electricity needs of millions of homes and businesses across six states.” Although energy storage technologies take different forms, their function remains consistent as a needed grid technology.