One way to save money on your heating bills and reduce your family's carbon footprint is to take advantage of the free energy produced by the sun every day. Solar energy has many uses around the home, from generating electricity to providing heat, and in certain parts of the country it can provide a significant amount of energy. Knowing the basics of the many home solar systems on the market can help you make the right choices for your particular needs.
Photovoltaic cells contain layers of silicon, which reacts when struck by sunlight to produce a weak electrical current. Solar panels contain multitudes of these cells, all connected, to extract as much electricity from sunlight as possible. These systems usually include a backup connection to another power source, storage batteries or a combination of the two to provide power during off-peak hours as well as overnight, when photovoltaic cells lie dormant.
Most manufacturers rate their solar panels by wattage, making it easy for the homeowner to estimate how many he will need to install to meet his energy needs. Keep in mind, however, that the numbers indicate the electricity generated in full sunlight, which may only occur for a few hours each day. You should also take into account your climate and distance from the equator; according to the National Renewable Energy Laboratory, a panel installed in the Arizona desert could produce two to three times as much electricity as one installed in the Pacific Northwest.
Allowing the sun to shine into your home can warm south-facing rooms, but it can be difficult to hang on to that heat when it is most needed. One simple form of passive heating requires tanks of water or other dense liquids; these absorb the sun's heat during peak hours and then radiate it as they cool. A trombe wall is another form of passive heating that involves a south-facing wall made of dense materials, painted black and covered with glass to leave a small airspace on the exterior side. The sun warms the wall during the hottest part of the day, and the trapped heat radiates inward once the sun goes down.
Although passive heating is efficient for heating individual rooms, if you want a whole-house solution, consider an active solar heating system. These systems use collectors mounted on the roof or exterior walls to warm water, which then flows through a series of pipes throughout interior walls. Active solar systems provide even heating throughout your home, but they require power to operate, and the installation costs can be extreme unless your home was designed with active solar heating in mind.
- National Renewable Energy Laboratory; Solar Photovoltaic Technology; Sept. 29, 2009
- National Renewable Energy Laboratory: Average Daily Solar Radiation per Month
- U.S. Department of Energy; Direct Gain; Feb. 9, 2011
- U.S. Department of Energy; Indirect Gain (Trombe Walls); Feb. 9, 2011
- Union of Concerned Scientists; How Solar Energy Works; Dec. 16, 2009
- U.S. Department of Energy; Liquid-Based Active Solar Heating; Feb. 9, 2011
Milton Kazmeyer has worked in the insurance, financial and manufacturing fields and also served as a federal contractor. He began his writing career in 2007 and now works full-time as a writer and transcriptionist. His primary fields of expertise include computers, astronomy, alternative energy sources and the environment.
- Photos.com/Photos.com/Getty Images