Basics of Solar Power
Solar power is a non-polluting, renewable, completely free and abundantly available energy source, and for many years now experts have been putting their minds to the question of how to best and most efficiently make use of it. Here are some basic points about solar power and about how it is being used at present:
Solar power can be used in a wide variety of different ways: it can be converted into electricity by means of photo voltaic cells, and it can also be used directly as a means of heat, for example for heating water. Using it directly in this way is frequently termed 'passive solar', whereas converting it into electricity is called 'active solar'. One of the main limiting factors on the usefulness of solar power is the relatively weak form in which we receive it, so that if we are to make really effective use of it we need to find a way to concentrate it.
People have used solar power in passive systems for hundreds, even thousands, of years, for example in lighting fires, heating water, drying wood, and so on. Solar water heaters are now in use in many places where sunlight is available for most days in the year, and there are also solar power plants in existence, which concentrate the sun's energy and generate large amounts of electricity. This kind of power plant is especially useful and economical in out of the way places where it is difficult to get conventional electricity. Solar power is even put to use in outer space, by satellites and space craft.
There has been a great deal of interest in recent years in using solar power to power motor vehicles, however this is still in the experimental stages of development. The difficulty here is that the amount of power required to supply the car's engine would need big solar panels, which are impractical on a moving vehicle owing to the panels' size and fragility. Also, at times when there is no sun these vehicles could only run for limited time. So these vehicles are not ready as yet to replace conventionally powered ones.
The demand for solar power is increasing, but at the moment its cost prevents it being used widely. It is not the lack of technology, but the cost of converting it to useful energy which is prohibitive. However fuel costs are continually rising, and the time will come when solar power will be economically viable. People are also increasingly concerned about the environmental impact of present day fuels, and therefore the demand for clean energy is rising. This increasing demand means that by economy of scale manufacturers will find it more feasible to produce devices which run on solar power.
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