03.05Solar Energy Fact 10
Fact 10: Solar energy represents the oldest form of energy. And there is a big chance it could turn out to be the most important answer to our energy problem.
Solar energy has existed for as long as the sun was born. Based on Wikipedia, our solar system was formed 4.6 billion years ago. It came from the gravitational collapse of a giant molecular cloud. This primal cloud was several light-years across and probably gave birth to several other stars as well. According to the meteorites study, the sun is formed from the shock waves of several supernovas’ explosions. The explosions caused many nebula regions to have overwhelmed density allowing gravitational forces to overcome internal gas pressure and collapsed forming the sun as we see today. Solar energy is the oldest form of energy known to mankind since we have been using it for thousands of years. Millenniums ago, human have been using solar energy to dry food and clothing. As early as the 7th century BC, some of us discovered that when the sun ray is directed through a piece of glass, fire could start if the ray shines on something flammable. About 2000 years ago, the Greeks were the first to use solar housing. Their design is rather ingenious at that time allowing the run ray to pass through during the winter but not in the summer. Another intelligence idea ahead of it time was solar trapping. More than a thousand years ago, the Roman learned how to trap sunlight by building glass windows. They even created greenhouses so they can have fruit and vegetables the whole year.
Perhaps the greatest usage of solar energy ever discovered was the ability to turn solar energy directly into electricity. It is all begin with an experiment about solar energy named the photoelectric effect. This experiment is proposed by Einstein himself in 1905. In 1921, he won the Nobel Prize for this original proposal. The theory proposed that if sunlight is shine on the metal with a specific frequency corresponding to that metal, current is produced. Since current is the flow of electron, electricity is produced.
In 1954, the first photovoltaic technology is born when Daryl Chapin, Calvin Fuller, and Gerald Pearson developed the silicon photovoltaic cell at Bell Labs. The first solar cell invented is able to generate enough power from the sun to run everyday electrical equipments. At this time, the conversion of sunlight energy to electricity is still inefficient. As time passed, with the aid of new technology, photovoltaic cells are becoming more efficient along with the drop in manufacturing cost. Today, the technology has reached a point where photovoltaic cells are available for residential housing.
With the impressive potential of photovoltaic technology, many large companies like British Petroleum, Shell and the oil companies are already invested in this field. With the assist of Nanotech, development companies like Nanosys, Nanosolar and Konarka are reaching photovoltaic cells at a very low level. With this, they are hoping to increase the efficiency of energy collection to the point that the cost of solar energy is as low as the cost of fossil fuels. Perhaps with this amazing discovery, human have unlocked the key to a clean and prosperous future
Sources
http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2005/07/11/BUG7IDL1AF1.DTL
http://en.wikipedia.org/wiki/Solar_system










