Can Solar Energy Power Electrical Appliances?

Determining Electrical Appliance Loads

• The primary way to know if a solar energy installation is going to generate enough electricity to power a home's appliances is to calculate the home's total electrical load. This is fairly easy to do, usually, as most appliances and electronics are labeled with their wattage. The most important factor is to determine the peak energy demand -- generally, the wattage needed to power the home when various different appliances are running. Some appliances run fairly constantly, like refrigerators and water heaters.

Photovoltaic Energy Systems

• Solar energy can power electrical appliances, depending on the size, sun exposure and efficiency of a home energy system. Some users of solar energy use the technology to increase their efficiency -- supplement, not replace, the energy that they get from the grid. Depending on local infrastructure, solar energy systems installed on homes can sell power back to the grid to offset the costs of energy consumption at night. Other systems store excess energy in on-site batteries that provide electricity when the sun is not available.

Solar Electricity vs. Solar Heating

• Some of the biggest consumers of electricity in most homes are heating appliances. Baseboard heaters and electric furnaces use electricity to generate heat, maintaining indoor temperatures. While solar electric systems can power these appliances, a more efficient alternative might be active solar heating, which deploys the warmth of the sun to heat living spaces. Sometimes these systems are used to supplement electrical heating appliances, which power the space when solar heat is not available.

Solar Water Heating

• As with furnaces and baseboard heaters, solar energy can power appliances like dishwashers and water heaters that use electricity to heat water. Some systems, though, replace the need for electricity to power these appliances by using solar energy to heat water directly. These systems are called solar water heaters, and in some applications they can reduce the need for electrical water heaters entirely. Solar water heaters come in several designs and vary in cost and application. Some designs use glass or plastic panels that create a greenhouse effect to heat water; others, called batch collectors, run water through black boxes that are exposed to sunlight.