Energy storage involves converting energy from forms that are difficult to store to more conveniently or economically storable forms. Some technologies provide short-term energy storage, while others can endure for much longer. Bulk energy storage is currently dominated by hydroelectric dams, both conventional as well as pumped.
The length of time an ESS can supply electricity varies by energy storage project and type. Energy storage systems with short durations supply energy for just a few minutes, while diurnal energy storage supplies energy for hours.
Electricity can be stored in a variety of ways, including in batteries, by compressing air, by making hydrogen using electrolysers, or as heat. Storing hydrogen in solution-mined salt caverns will be the best way to meet the long-term storage need as it has the lowest cost per unit of energy storage capacity.
Energy storage can be useful if you already generate your own renewable energy, as it lets you use more of your low carbon energy. It reduces wasted energy and is more cost effective than exporting excess electricity. For example, you can store electricity generated during the day by solar panels in an electric battery.
You can store electricity in electrical batteries, or convert it into heat and stored in a heat battery. You can also store heat in thermal storage, such as a hot water cylinder. Energy storage can be useful if you already generate your own renewable energy, as it lets you use more of your low carbon energy.
Energy storage solutions for electricity generation include pumped-hydro storage, batteries, flywheels, compressed-air energy storage, hydrogen storage and thermal energy storage components. The ability to store energy can facilitate the integration of clean energy and renewable energy into power grids and real-world, everyday use.