Ways to save money on heating & cooling in your home with solar energy
Solar energy is the most accepted renewable energy technology available today. It can be used to heat water, provide indoor lighting, and most importantly create electricity.
The most explosive sector of the solar energy industry is in "grid connected" solar systems. These systems are used in conjunction with your existing electricity supply to offset and stabilize your utility delivered energy. They produce electricity when the sun is shining, and draw energy from the electric grid when it is not shining.
Many states offer attractive incentives for the purchase and installation of solar systems, and compared to wind energy technology, there is an abundant amount of information available to determine if solar is right for you. Look through the information below to determine if your location has enough solar energy and possible incentives to make installing a solar system a good choice for you.
Aside from the cost savings, the use of solar energy has zero effect on the environment. If the negative effects of burning fuel become a factor, the use of solar energy becomes a benefit to the environment.
Solar heating systems fall into two categories: passive and active. Passive systems use the sun’s rays to heat a surface directly, storing the heat in a mass of concrete, rock, or water. At night the heated mass radiates the heat into the desired space. An active system collects the sun’s energy in a medium such as air or water and pumps it to a storage facility, then pumps the heated medium to the space as needed. The newest active systems use special solar cells to convert the sun’s rays to electricity and use it as it is generated or store it in batteries to be used as needed.
A passive system has no moving parts other than motorized shades or insulation barriers to prevent heat loss at night through the glazing. The most common passive system consists of a large room that resembles half of a green house with a wall of glass or other transparency facing due south or north (dependent on the building location in respect to the equator) to prevent infiltration of outside air. The solar radiation becomes heat energy as it passes through the glazing and strikes the storage medium. A wall of concrete, a floor of concrete or stone, or large vertical cylinders filled with water are used to store the heat. At night, as the temperature of the home drops, doors between the storage room and the house are opened so the warmth that has been stored will radiate into the air and temper the home. Insulated shades or blankets covering the glazing during the night will keep external heat loss to a minimum.
Active systems are more complex. The solar radiation that passes through the glazing falls on a collector plate. The plate can be a duct with air flowing through or a plate with loops of piping carrying water or refrigerant that is warmed and pumped to the space to be heated or to a storage facility. If air is used as the medium, a large bin of rocks or a layer of rocks beneath the floor of the house will absorb the heat to be stored. If water is the medium, it will be pumped to a tank, and can be circulated to a conventional radiator system when heat is needed. If a refrigerant is collecting the heat, it will follow the same design as a heat pump system. Water will be heated in an exchanger and stored for later use. The refrigerant system eliminates the need for anti-freeze protection and drain down that a water system requires.
With additional piping and a heat exchanger, all solar heating systems can produce domestic hot water. The earliest solar systems were for domestic hot water supply, then expanded to meet the heating demands of the home or to heat swimming pools.
As a free source of energy, many unique methods of collecting and storing solar radiation have been installed in homes and office buildings over the years. There are so many, they cannot easily be categorized. Many books have been written listing the thousands of applications, each one exclusive to the needs of the structure.
It’s easy to overlook the obvious. If you want to stay cool, stay in the shade. Well, you can’t shade your whole house, but you can use sunscreen fabrics to shade the windows, porches, picnic tables, and even air conditioners and swing sets.
In 2001, Phifer Wire Products claimed that its solar screen blocked 65 to 90 percent of the sun’s heat. The screens snapped in place on the outside of the window. The idea was it bounced the solar energy back toward the outside before it entered the glass. This method prevented hot spots.
The screen was made from vinyl-coated synthetic yarn that was woven together to provide strength and increased shade. Later versions of this screen are still produced today. Along similar lines was Easy Gardener’s Sun Screen Fabric. The company said its lock-stitch fabric was preshrunk to not sag, even after being exposed to wide fluctuations of heat and humidity. The fabric could be cleaned with a garden hose.
Screens like these are efficient ways of keeping your home cool during the summer months and keeping the HVAC from running as often to keep the home cool. It’s both effective in keeping your utility bills down and heat down inside the home from outside solar rays. Another alternative, if not screens, is trees. While they take longer to grow to heights for shading, they’re a great idea for the hot summer months by providing shade to your home from the sun’s rays.