PV Gap

Billy Said:

Can you get energy at night from solar panels?

We Answered:

There are a number of ways to produce small amounts of energy at night from solar panels. Here is an example of one: http://www.youtube.com/watch?v=roLWoFIjk…

Electricity is more difficult to store. Putting electricity on the daytime grid and taking power away later is more like a banking system than storage but the results can be the same. If everyone were using solar energy power lines would have to wrap the globe to keep the power flowing.

Electricity can be shifted to other energy trapping means which are later used to produce electricity. Pumping water behind a dam, chemical bonds in batteries, pressure in a compressed air energy storage system, flywheels, and splitting water into hydrogen and oxygen are all methods that have been used to store energy to later produce electricity. Only ultra capacitors store electricity directly as a charge. Of these batteries are the most energy dense and efficient method but they are heavy and expensive.

Energy can also be stored as heat. Thermal solar panels are many times more efficient at collecting the sun's energy than photovoltaic panels. The heat energy is stored in a thermal mass like water, concrete or stones. Phase change materials can store much higher amounts of heat that is locked into a change of phase from solid to liquid or liquid to gas. It is possible to use stored heat to produce electricity. This is what power plants do. But thermal solar panels would have to b used to run a stirling engine. This has already been done with parabolic dish solar collectors with commercial success.

A solar chimney stores its own heat at night which is extracted with wind turbines: http://www.youtube.com/watch?v=XCGVTYtJE…