Solar Power
Energy from the Sun is virtually limitless and provides the basis of life on Earth. When that energy is converted into something useful, it becomes solar power. Plants also transform sunlight into food energy through photosynthesis. Modern technology transforms solar energy into electrical power (electricity) with the use of photovoltaics PV). It converts solar energy into electricity by “exciting” the electrons of an atom into a higher state of nuclear orbit. The most efficient photodiodes (produces electric current when light is shone on it) for photovoltaics are those made from silicon-derived materials. Solar cells produce direct current electricity (DC) and were first used to power spacecrafts on their long journey or power orbiting satellites. More practical uses of this DC power nowadays include telecommunications cell sites, the cathodic protection of oil pipelines (from rust), roadside emergency telephones, and remote sensing. Its other uses are for remote fixed devices like temporary street signs or permanent traffic lights, or for portable devices such as calculators, computer laptops and wristwatches.
Solar Power
Issues against solar power are capital cost (materials and labor cost of installation) and like wind, it is also intermittent and therefore not as reliable as one would like. However, due to increasing demand, manufacturers are now able to reduce their prices of solar panels. In 2007, some investors have found an opportunity in electricity generation: in return for a long-term 25 -year contract, they will install solar panels for free and will buy electricity that will be generated at below present utility rates. They will then sell this electricity to electric power grids at a higher price and profit the difference. Homeowners who pay and install their own solar panel arrays also sell their excess electricity to power utility companies. In their case, they just connect their solar system into the power grid and can see their electric meter turn backwards! Incredible!!!
The website above is that of Nanosolar, a new high-tech firm in California that developed more radical way of making solar cells – by just printing them on a substrate of paper rather than the conventional manufacturing process of using thin-film silicon wafers on a substrate of steel. It was given an Inventor’s Award for making solar electricity between 10-25 ways cheaper now. It uses a special ink that re-arranges the solar circuits on a molecular level just by themselves. The small firm has leveraged its nano-technology to make solar panels easier and cheaper to mass-produce, highly cost-efficient, very flexible to install and fantastically simple to use. Their “PowerSheet” solar cell has made solar power cheaper than coal for the first time ever.