How Do You Store Solar Energy Without Batteries?

pumped hydro

While batteries dominate new installations, most existing storage capacity is actually pumped hydro, which uses surplus electricity to pump water into reservoirs. When electricity is needed, water can be flowed through turbines to generate electricity, much like traditional hydroelectric power. Pumped hydro is generally cheaper and has higher capacity than other types of storage. It is also 80% efficient and can utilize existing hydropower infrastructure, thereby promoting green energy.

Underground pumped hydro storage

The disadvantage of pumped hydro is that it is difficult to find a suitable location and build there. As a result, a number of underground water storage projects are now being developed.

These strategies utilize existing underground infrastructure. For example, an abandoned mine near a quarry. Other companies have developed a technology called geomechanical pumped hydro, which stores water between shale rock formations and can be installed in places such as beneath farmland.
gravity storage

Traditional pumped hydro relies on gravity to store and release energy. Gravity storage is a similar concept - but without water. Instead, it relies on raising and lowering giant slabs of bricks or rock, which allows them to be built almost anywhere.
Although gravity storage power generation technology has broad application prospects in theory, it still faces some challenges in implementation. One of these is finding suitable geographical conditions and sites to ensure adequacy of height differences and storage capacity. In addition, advanced control systems and automation technologies are needed to achieve precise control of the energy storage and release process.