The amount of energy from the sun that hits the Earth’s surface is enormous.
Did you know that the energy from just 20 days of sunshine is the equivalent to all the energy stored in Earth's reserves of coal, oil, and natural gas?
Outside Earth's atmosphere, the sun's energy contains about 1,300 watts per square metre. Around one-third of this light is reflected back into space.
This energy has fallen to about 1,000 watts per square meter by the time it reaches the Earth's surface.
If you took an average over the entire surface of the planet, 24 hours per day for a year, each square metre collects the energy equivalent of nearly a barrel of oil each year. So you can see how solar power panels can be so beneficial and economical to mankind.
The basics of solar power
There are many solar energy advantages.
Solar panels are one of the cleanest, most viable form of renewable energy available and they can be used in several forms to help power your house and combat global warming.
Solar energy — power from the sun — is free and inexhaustible.
Basically, solar energy underpins all life on Earth and is the basis for almost every form of energy we use. The sun makes plants grow, which can be used as biomass fuel. If these same plants were left to rot, over time, they would eventually turn into coal and oil.
Passive Solar Design for Buildings
One simple, obvious use of sunlight is to light our buildings.
If properly designed, buildings can capture the sun's heat in the winter and minimize it in the summer, while using daylight year-round. Buildings designed in such a way are utilizing passive solar energy, a resource that can be tapped without mechanical means to help heat, cool, or light a building.
South-facing windows, skylights, awnings, and shade trees are all techniques for exploiting passive solar power. Buildings constructed with the sun in mind can be comfortable and beautiful places to live and work.
Residential and commercial buildings account for more than one-third of U.S. energy use. Solar design, better insulation, and more efficient appliances could reduce this demand by 60 to 80 percent.
There are several hundred thousand passive solar homes in the United States, but there should be many more. Simple design features such as properly orienting a house toward the south, putting most windows on the south side of the building, and taking advantage of cooling breezes in the summer are inexpensive yet improve the comfort and efficiency of a home.
Solar Energy Thermal Collectors
Besides using design features to maximize their use of the sun, some buildings have systems that actively gather and store solar energy.
Solar panels, for example, sit on the rooftops of buildings to collect solar energy for space heating, water heating, and space cooling.
In 1984, for example, 16 million square feet of solar panels were sold in the United States, but when fossil fuel prices dropped and tax credits expired in the mid-1980s, demand for solar panels plummeted.
Today, about 1.5 million U.S. homes and businesses use solar water heaters — still less than one percent nationwide. In other countries, solar panels are much more common;
Israel requires all new homes and apartments to use solar water heating, and 92 percent of the existing homes in Cyprus already have solar water heaters. But the number of Americans choosing solar hot water could rise dramatically in the next few years. With natural gas prices at historically high levels, solar water and space heaters have become much more economic.
According to the U.S. Department of Energy, water heating accounts for about 15 percent of the average household’s energy use.
As natural gas and electricity prices continue to rise, the costs of maintaining a constant hot water supply will increase as well. Homes and businesses that heat their water through solar panels could end up saving as much as $250 to $500 per year depending on the type of system being replaced.
For more information about solar water heating for homes and swimming pools go to my diy solar heating kits section.
Solar Thermal Concentrating Systems
By using mirrors and lenses to concentrate the rays of the sun, solar thermal systems can produce very high temperatures—as high as 3,000 degrees Celsius. This intense heat can be used in industrial applications or to produce electricity.
Pretty neat eh?
Useful resources
For more information on solar power how it works click on the link.
Click on solar photovoltaic energy for information on solar for electricity.
Click on our solar power gadgets for great gift ideas.
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