One of the most common storage options for energy generated by a solar array is standard automotive batteries and deep cycle marine batteries. While charging, these batteries store electric potential energy as chemical energy for on-demand conversion back to electric potential energy. This process involves moving electrons from one material into another for storage. The electrons are then moved back between these materials in order to convert the stored energy back into electric potential energy.
Another option that has become increasingly popular is to convert the radiant energy from the sun into heat energy. By focusing the sun's radiation, it is possible to melt salt in order to store this energy for future use. Once stored, the heat energy can be converted into electric potential energy at night and on cloudy days. This method is being used by some newly designed solar power plants in order to increase power production and reduce outages. This method of storage using molten salt is particularly suited to the needs of large power grids.
Since batteries use volatile, dangerous and poisonous chemicals, it is easy to see why another chemical storage alternative has been developed that uses water. The electric potential energy that is collected from a solar array is directed into a process called electrolysis. This process splits water molecules into their constituent components, hydrogen and oxygen. The hydrogen is then stored in tanks and can be converted into heat energy by simply burning the gas, or transformed into electric potential energy using fuel cells. The storage of solar energy through electrolysis is well suited for home power generation and storage.