To balance electricity load, how can solar energy be stored? Without storage, electricity must be generated and consumed simultaneously, which could mean grid operators need to take some power offline or "shed" some generation to avoid overgeneration and grid-reliability issues. On the other hand, there may be other times when solar generation is low but demand for electricity is high, such as at sunset or on cloudy days. Enter storage, which can be filled or charged when generation is high and consumption is low, and then distributed when loads or demand is high. When some of the power produced by solar is stored, this power can be used by grid operators when needed, including after sunset. In this way, storage serves as an insurance policy for sunshine.
"Fixing" solar power, short-term storage can ensure that rapid fluctuations in power generation don't have a big impact on the output of a solar power plant. For example, a small battery can be used to bridge short interruptions in generation caused by passing clouds, helping to maintain a reliable and consistent supply of "stable" electricity to the grid.
Providing flexibility, how can solar energy be stored? Solar energy and storage can provide backup power during electricity interruptions. They can keep critical facilities running to ensure continued basic services, such as communication. Solar energy and storage can also be used for microgrids and small-scale applications, such as mobile or portable power devices.
How can solar energy be stored? The most common type of storage in the grid is pumped hydro storage. But the most common storage technology used in conjunction with solar power plants is electrochemical storage (batteries) for photovoltaic (PV) plants and thermal storage (fluid) for CSP (concentrated solar power) plants. Other types of storage, such as compressed air storage and flywheels, may have different characteristics, such as very fast discharge or very large capacity, making them attractive to grid operators.
Solar fuel: how can solar energy be stored? Solar energy can be used to create new fuels that can be burned or consumed to provide energy, effectively storing solar energy in chemical bonds. Possible fuels being studied by researchers include hydrogen, which is produced by separating it from oxygen in water, and methane, which is produced by combining hydrogen and carbon dioxide. Methane is the main component of natural gas, typically used for power generation or heating.