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NEW!
Clean Energy: The Next High Tech Revolution
As the nations of the world deliberate here in the Hague
over the next 10 days to accelerate international action to reduce
greenhouse gas
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Green EnergyEnergyEnergy is the ability to do work. It allows us to generate the electricity needed for our homes, businesses, schools and factories --for lighting, powering our household appliances such as televisions and radios, refrigerators, washing machines, air conditioners and computers. Energy enables people to travel great distances by land, air and sea. All around us, energy is what makes things move, light up, give off warmth ... in other words, energy is what makes things happen. It is what gives us the power we need to do work. You need energy to run, hit a ball, do school work, read, take a hot bath or even to sleep - yes, even to sleep. All living things need energy to live. Where do we get this energy? From the food we eat, which has energy in it. For millions of years, humans relied on energy in their own muscles to do work. Then, it was discovered that using wood and coal, fire could cook food, and warm living spaces, that wind could propel sailing ships/vessels and a flowing river could turn a waterwheel and create power. Animals were also tamed as new sources of energy. The steam engine was developed using steam to produce energy to run machines. This made work easier and more productive. The discovery of electricity and the internal combustion engine created an even more important way of using energy. A new era of the use of energy began with the application of nuclear energy. Today, we use huge amounts of energy - to move, lift, warm, cool, cook or light things. Energy is one of the basic necessities of our universe. It has aided in development and improved living standards all over the world. It is the engine of growth and progress. Energy comes from several different sources. Currently, global energy use depends heavily on fossil fuels, such as oil, coal, and natural gas, which are referred to as non-renewables, because they cannot be replaced. They are called "fossil fuels" because they were formed between 350 million and 50 million years ago from the remains of prehistoric plants and animals. These were chemically changed through the action of heat from the earth and pressure from rocks above into oil, natural gas and coal. For many years, coal served as the world's primary fuel - in the 1920's, it supplied over 70% of the world's energy. Now, however, it supplies only 26%. Today, much of the world's energy supply comes from crude oil, although natural gas, which currently supplies 23% of the world's energy needs and is the fastest growing fuel source, is becoming increasingly more important to the world energy mix. Experts anticipate that the remaining amount of accessible fossil fuels will last another 170 years at the present rate of consumption. Another nonrenewable source is uranium. Uranium is an element that gives us nuclear energy, by splitting an atom's nucleus by a process called fission, which releases a tremendous amount of energy. This energy when let out slowly, can be harnessed to generate electricity. When it is let out all at once, it makes a tremendous explosion as in an atomic bomb. While it is one of the cleanest ways of generating power as far as air pollution goes, generating electricity from nuclear energy is quite controversial. Since 20% of US electricity and over 15% worldwide is derived from nuclear generators there is little doubt it will be used for many years to come. The fear of meltdown and the dilemma posed by long-term disposal of waste combine to make many people wary. Since at least the third millennium B.C. when great civilizations evolved around major rivers such as the Nile, Tigres-Euphrates and Indus, and from the onset of the Industrial Revolution in the 18th century running water has been used to provide irrigation, supply water, control floods and provide motive power and electricity. The use of plant and other organic material for power even precedes water by centuries. In recent decades, technologies have been developed that harness the energy of the sun, the wind, the earth and even the ocean. While current supplies of coal, oil, and natural gas are finite and will eventually run out, wind and solar are examples of renewable energy. These sources are not limited and can be tapped indefinitely. More energy will be needed to fuel global socio-economic growth and sustainable development. In particular, to bring economic opportunities to billions of people in developing countries, many of whose choices in life are severely constrained by poverty and limited access to modern energy services. The amount of additional energy needed to provide the requisite energy services depends on the efficiencies with which the energy is delivered and put to use. However, if the current global growth rate of 1.7% per year of primary energy use (2.5% growth in developing countries) continues, that will mean a doubling of energy consumption by the year 2030 compared to 1995, and a tripling by the year 2060. This will probably be driven by increases in global population and standards of living. This increasing demand for energy poses serious environmental & health challenges, however. The most challenging by far is that of global warming. Already the production and use of energy causes more environmental damage than any other human activity, contributing almost 80% of the pollutants that cause air pollution and more than 88% of the greenhouse gas emissions that are responsible for global warming. For more on greenhouse gases and the science of climate change see our climate change section.
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