Where we are

Currently, there is not much large scale energy storage being used. There are a few systems that use pumped storage to generate excess energy for when demand is high. There is about 90,000 megawatts of pumped water storage capacity in the United States. There is also a good amount of research going into the other possible systems, especially new battery technology. For example, a small wind farm in Minnesota is attaching the wind turbines to a large battery pack that can take up 7.2 megawatt hours of power from 7 nearby wind turbines. This ensures that the energy is always eventually used and that the wind field can provide a more stable amount of electricity to the grid, just like a fossil fuel power plant would.

These systems are starting to get more of a focus now as a result of the desire to invest in renewable energy technologies. This new research will be able to help the existing grid too, however, as mentioned in the Why It's Important section. Up until now, there just hasn't been the incentive to work on these systems because of the amount of research that needed to go into them and the lack of cost for using inefficient, highly polluting power plants. When energy is cheap and emissions free, there is not much in the way of incentive for utility companies to invest in storage mechanisms.