Many of us think nothing of picking up a small calculator in order to add up some figures. Many of those little calculators run on photovoltaics, which is a type of solar cell that can produce electricity. Although current photovoltaic solar cell technology has succeeded in creating electricity that can run smaller electrical appliances and other items, such as electronics and water heaters, there is a great deal of excitement and work going on in the area of creating photovoltaics that are efficient enough to run entire cities, giving them years of free electricity derived from sunlight.

So let's say that you have a water heater in your home, and you would like that water heater to run on solar electricity. Such water heaters are currently available, and you may have seen them, but were unsure about how the mechanism of converting sunlight to electricity could actually work so that your water heater would reliably give you hot water when you want it.

Although it can be a complicated process, here is how photovoltaic solar cells work in words that homeowners without an upper-level science degree can understand. In order for the photovoltaic solar cell to create electricity, it first has to capture energy from sunlight. This happens through the use of a semiconductor material inside the solar cell. New technologies have been created so that this semiconductor material can be microscopically thin, and yet still create electricity, giving it applications around the house that had heretofore been unheard of. As thin as tinfoil, or coming in the form of a liquid that can be painted on surfaces, these thin film solar cells are revolutionizing how solar cells can be used in homes.

The energy from sunlight has a tendency to zip around the solar cell with no set pattern, so in order to create electricity the next step is to introduce an electrical field to the solar cell. This helps to regulate the flow of the energy's electrons, which turns it into usable electrical current. You can tap into that usable electricity as you would with a regular battery, by using metal contacts on either end of the solar cell.

The number of solar cells that are joined together in your solar cell array, as well as how efficient they are, will determine how much voltage the system will produce. There are solar systems that can make sure your water heater heats water when you want it, or the electricity could be used for other electrical appliances around your home as well.