Solar Power Generation possible during night time? Yes. As you know the output of a solar power plant depends on the time of day and cloud cover. To generate power from the solar power plant, you need to store the solar energy. Here we will discuss various methods to store the solar energy for power production during night. Different ideas have been cooked up by researchers for storing the power created by solar power plants – batteries, ultracapacitors, fuel cells, hydrogen generation, flywheels – but all of these are far from being affordable enough for large scale power needs. The better alternative is to store power as heat before it’s converted to thermal energy.

Solar Electric Energy Storage

This is the traditional method of storing solar generated power in the form of electrical energy, with the use of batteries, fuel cells, ultracapacitors, hydrogen generation, flywheels – but all of these are far from being affordable enough for large scale power needs.

Solar Light storage Systems

Still this method is in research, and some of the scientists trying to prove this technique as a viable night solar power generation method. In this case the solar light is captured and saved using certain crystalline materials. With the help of powerful mirrors, the stored light energy further can be used for power generation during night. This technique is not suitable for large-scale power plants. Also it is very expensive to make light energy storage crystalline glass/fiber devices, which can store a small amount of energy.

Solar Heat Energy Storage Tanks

The materials, which include new mixtures of salts as well as new glass materials, could be key to making solar-thermal power plants cheap enough—and reliable enough—to compete with fossil fuels on a large scale. Electricity from a solar-thermal power plant costs roughly 10 cents a kilowatt-hour, both with and without molten salt storage systems.

The salts—a mixture of sodium and potassium nitrate, allow enough of the sun’s heat to be stored that the power plant can pump out electricity for nearly 12 hours after the sun starts to set. It’s enough for 12 hours to produce energy with full capacity of upto 100 megawatts.

Part of a so-called parabolic trough solar-thermal power plant, the salts will soon help light up the night—literally. Because most salts only melt at high temperatures (table salt, for example, melts at around 1472 degrees Fahrenheit, or 800 degrees Celsius) and do not turn to vapor until they get considerably hotter—they can be used to store a lot of the sun’s energy as heat. Simply use the sunlight to heat up the salts and put those molten salts in proximity to water via a heat exchanger. Hot steam can then be made to turn turbines without losing too much of the original absorbed solar energy.

To allow the salts to get hotter, some companies are developing so-called power towers—vast fields of mirrors that concentrate sunlight onto a central tower. Because of the centralized design such a structure can operate at much higher temperatures—up to 1,000 degrees F (535 degrees C)—and use molten salts directly as the fluid transferring heat in the power plant. The heat melts the salt, which boils water around it, and the steam generated turns the turbines. The salt tanks’ ability to retain heat is what affords the plant up to 15 hours of sunless energy generation.