What Is Solar Power?

What Is Solar Power?

“Solar power” is the conversion of the abundant energy of sunlight into a form that can be used for purposes sunlight doesn’t serve directly. The most common meaning of the term involves the conversion of sunlight into electric power, through the use of solar panels for your home normally, and that’s what will be discussed here.

Advantages of Solar Power

The amount of energy from the sun is enormous, and it flows continually in abundance whether we make use of it or not. Less than one part in 8,000 of the sunlight striking the Earth could supply all of the energy needs of the entire population of the planet. Domestic solar power is also free to use, inexhaustible, and non-polluting. It’s adaptable to all energy uses, both large and small.

The cost of solar panels and other components of solar power systems is falling rapidly as the technology progresses. At the same time, the cost of fossil fuel energy is expected to rise dramatically due to the effects of “peak oil” and of increasing global demand. For this reason, domestic solar panels present increasing economic advantages along with its abundance and environmental benefits.

How Do Solar Panels Work?

Solar roof panels are collections of photovoltaic cells that convert sunlight directly into electricity. Photovoltaic cells are constructed of semiconductors such as silicon (the most common material used). When sunlight strikes a semi conductive material such as silicon, a part of it is absorbed by the material, and the process of this absorption energizes electrons within the material, some of which are freed to flow
as current.

Metal contacts placed at the ends of the photovoltaic cell allow the current to be drawn off and conducted away for use. The result: solar power! A solar panel is made of multiple solar cells that together generate a flow of power usable for various purposes, such as to power a home. Solar panels are measured in wattage and also in area or square inches of surface.

Solar Power For Home Use

How much area of solar panel would be required to provide solar power for a typical house? That depends on how much power the home uses, which varies depending on the size of the home, the energy efficiency, and what type of appliances are in use.

It also varies by where you live; a home in southern Arizona receives more dependable solar power than one in northern Minnesota.

A typical home that does not use electricity for heating or air conditioning and is not particularly energy-efficient might use between 10,000 and 15,000 watt-hours per day. To produce that much power in an area where a solar array generates 70 milliwatts per square inch in full sunlight would require a rooftop solar system consisting of 285 square feet of solar panels, or about a 16′ x 16′ array.

Of course, if someone were using solar power to partially reduce energy consumption from the grid rather than to achieve complete self-sufficiency, a smaller array would be sufficient. But it’s easy to see that the main expense of solar power is in the initial cost of materials and construction rather than in any ongoing costs such as fuel. If you build your own solar panels and install them yourself you can significantly reduce this cost.

On Grid or Off Grid?

A home solar power system can be designed either to be “on-grid,” which means the home is still connected to the local electric utility and runs on a mix of solar power from the array and conventional power, or “off-grid,” which means the home runs on solar power from the home array completely.

In either case, a battery is normally used to allow use of the system during times when the sun isn’t shining.