Solar Energy Basics       

The sun produces radiant energy in the form of sunshine. You can feel the energy when you are outside and the sun is shining on you. The sun radiates an enormous amount of energy. Where does the energy come from that constantly radiates from the sun? Well, the sun is a big ball of gases, mostly hydrogen and helium atoms. The hydrogen atoms in the sun’s core combine to form helium and generate energy in a process called nuclear fusion. Basically, the sun's hydrogen atoms come apart and their nuclei combines to form hydrogen. The excess energy produced during this process is emitted into space as radiant energy. It takes about eight minutes for this radiant energy to reach the earth. When the sunshine hits the earth's atmosphere, some is reflected back into space, but the remainder hits the earth's surface. It is this radiant energy that can be used freely as a power source.

Capturing the Sunshine with Solar Collectors

Anything the sunshine strikes can be considered as a solar collector. The ground absorbs the sunshine and converts it to heat; a closed car allows the sunshine inside through the windows where it strikes the interior surfaces and heats the air. Greenhouses work in the same manner, absorb the sunlight, convert it to heat and retain the heat to warm the interior. This is nothing new and we all know how it works. The trick to collecting this energy is putting something in the path of the sunshine that will produce desirable energy such as a photovoltaic cell (for direct conversion to electricity) or a solar water heater (for capturing this energy and storing it in water for our use). This is where solar systems come into play. They capture the sunshine and energy for a useful purpose.

How Much Sunshine Can I Collect?

How much sunshine you receive at your location depends on several conditions. These include the time of day, the season of the year, the latitude of the area, and the clearness or cloudiness of the sky. For years weather data has been collected which allows you to determine how much sunshine falls in your area of the country. The technical term for this is called Solar Irradiance and it is particular to your location. There are a number of sources available to determine the solar irradiance value which will be discussed later.

Using the Sunshine to your advantage

There are many ways to use the sunshine to your advantage; you can heat water, heat air, make electricity, run a small motor, use a concentrator (much like a magnifying glass) and even more. The most popular uses for residential and commercial buildings is to produce hot water or electricity. Both uses require solar panels to be installed and wiring/piping to be connected from the solar panel to building.

Solar Energy Costs

Lets get the cost discussion out of the way and summarize it as slightly expensive depending on your use. I am not trying to tell you it's a bad investment, just that it will cost money to save money. Payback time on the systems range from a few years to multiple years with solar water heating being the best investment. The cost of energy has always gone up and will continue upwards. Rising oil prices will continue. The good news is that the cost of Solar Energy continues to go down as manufacturing efficiencies increase. Solar energy is increasingly desirable and economically feasible. Note that systems constructed by do-it-yourselfers can be extremely cost effective.