How Do Solar Panels Work at Night?
- A solar panel works by using an array of solar cells made from a semi-conducting material such as silicon. The cells capture photons emitted from the sun and convert the energy by causing electrons within the cell to become conductive and to release the energy as heat. This heat is used to warm water or to create electricity to be used immediately or stored for future use.
- The energy captured is used to heat water which is pumped through the solar panel. The water pipes and reservoirs are painted black to absorb as much heat from the sun as possible. The hot water is fed back into the home's normal hot water system and stored in an insulated tank ready to be used during periods of little or no light. This type of system supplements the main energy source for heating water in the home.
- Some types of solar panels are photovoltaic, which means they produce electricity directly. This type of panel is used on solar powered cars or road signs. The electricity produced is stored in a battery or batteries and can be used to power electric motors and systems even during the hours of darkness. When the batteries are exhausted, the solar panels will not be able to produce more energy until they capture enough of the sun's radiation.
- Solar panels require sunlight to operate at their maximum efficiency, but they are capable of working on cloudy days. Scientific breakthroughs in the production of new materials enable some solar panels to work in very low light. Using silicon and an experimental crystal compound, solar panels could be made that are up to 40 percent more efficient than traditional silicon-only panels. It is doubtful that there will ever be a solar panel able to produce electricity in complete darkness.
- As the world's demand for energy increases, so does the need for more efficient ways to meet those needs. Fossil fuels are expected to begin running out in the middle of the 21st century making renewable energy critical as a source of power generation. Solar power plays an important role in the renewable energy sector and with more efficient technologies enabling more of the sun's energy to be transformed into power, it will provide communities enough energy to keep the lights on through the night.
