Since solar energy can only be generated when the sun is shining, the ability to store solar energy for later use is important: It helps to keep the balance between electricity generation and demand. This means that developing batteries or thermal storage . Sometimes energy storage is co-located with, or placed next to, a solar energy system, and sometimes the storage system stands alone, but in either configuration, it can help more effectively integrate solar into the energy landscape. What Is Energy Storage? “Storage” refers to technologies that. Interconnection standards define how a distributed generation system, such as solar photovoltaics (PVs), can connect to the grid. Transmission lines carry high voltage electricity from centralized power plants to a substation.