The Capabilities of Energy Storage
Battery energy storage is an emerging technology within the electric power industry that has the capability to solve a number of challenges in achieving a more sustainable system. In one instance, energy storage could be used to solve the problem of the intermittency of renewable energy sources, allowing for the scheduling of this power to be more definitive. Alternatively, electric energy storage could be used as an energy time-shift by storing electric power produced during off-peak periods when prices are low, to be used for later use or sale when demand and prices are high. This would also apply to renewable sources, and storage facilities could store energy when, for example, the wind is blowing at night but demand is low, and discharge the energy during the day when the wind is not as strong, but demand is high. The Department of Energy declared that, “developing technology to store electrical energy so it can be available to meet demand whenever needed would represent a major breakthrough in electricity distribution.”
Ancillary services are the services necessary to support the transmission of electric power from seller to purchaser to maintain reliable operations of the interconnected transmission system. This power is used to help with the scheduling of electricity transmission, control voltage, and prevent energy imbalance that is caused when there is a difference between actual energy delivered to a load and the energy scheduled to that load. Energy storage has the capability to supply ancillary services because it can quickly provide energy to respond to changes in load or fluctuations in production from power plants. In contrast, for most energy sources it takes utilities considerable time to “ramp-up” or “ramp-down” production. Energy storage could improve transmission by enhancing reliability and compensating for disturbances on the system (such as outages or error), and alleviate congestion by storing energy and discharging during peak demand periods. These are just a few of the potential uses of energy storage.
