Friday, October 26, 2012

Solar Energy

Every hour the sun beams onto Earth more than enough energy to satisfy global energy needs for an entire year. Solar energy is the technology used to harness the sun's energy and make it useable. Today, the technology produces less than one tenth of one percent of global energy demand.
Many people are familiar with so-called photovoltaic cells, or solar panels, found on things like spacecraft, rooftops, and handheld calculators. The cells are made of semiconductor materials like those found in computer chips. When sunlight hits the cells, it knocks electrons loose from their atoms. As the electrons flow through the cell, they generate electricity.
On a much larger scale, solar thermal power plants employ various techniques to concentrate the sun's energy as a heat source. The heat is then used to boil water to drive a steam turbine that generates electricity in much the same fashion as coal and nuclear power plants, supplying electricity for thousands of people.
In one technique, long troughs of U-shaped mirrors focus sunlight on a pipe of oil that runs through the middle. The hot oil then boils water for electricity generation. Another technique uses moveable mirrors to focus the sun's rays on a collector tower, where a receiver sits. Molten salt flowing through the receiver is heated to run a generator.
Other solar technologies are passive. For example, big windows placed on the sunny side of a building allow sunlight to heat-absorbent materials on the floor and walls. These surfaces then release the heat at night to keep the building warm. Similarly, absorbent plates on a roof can heat liquid in tubes that supply a house with hot water.
Solar energy is lauded as an inexhaustible fuel source that is pollution and often noise free. The technology is also versatile. For example, solar cells generate energy for far-out places like satellites in Earth orbit and cabins deep in the Rocky Mountains as easily as they can power downtown buildings and futuristic cars.
But solar energy doesn't work at night without a storage device such as a battery, and cloudy weather can make the technology unreliable during the day. Solar technologies are also very expensive and require a lot of land area to collect the sun's energy at rates useful to lots of people.
Despite the drawbacks, solar energy use has surged at about 20 percent a year over the past 15 years, thanks to rapidly falling prices and gains in efficiency. Japan, Germany, and the United States are major markets for solar cells. With tax incentives, solar electricity can often pay for itself in five to ten years.

source: http://environment.nationalgeographic.com/environment/global-warming/solar-power-profile/

Wednesday, October 24, 2012

Cheap DIY solar energy system

Site is designed to help and inspire hobby and other beginners with  easy to understand basic information about solar electricity generating projects.

Whether you are building a new home, looking at a few renovations, or just wish to cut your energy bill, passive solar energy and cooling formulas are an easy way to incorporated green ideas into your home. With the rising interest in environmental issues, they make an excellent selling feature and they will save you money.








Solar energy is an alternative energy source that involves harnessing the radiant light energy emitted by the sun and converting it into electrical current. So to put it in other way it helps you to slash your power bill.


This is a great way to save on your power bill and to use a green energy power too. I have found a great page that will help you in this easy and affordable quest. 
All you have to do is to follow the instructions and in no time you will be saving lots of money on your power bill.