In this era of increased global warming and diminishing fossil fuel supplies , we must begin to put a greater priority on harnessing alternative energy sources . Fortunately , there are a number of readily available , renewable resources that are both cost-effective and earth-friendly . Two such resources are solar power and geothermal power.Solar energy , which reaches the earth through sunlight , is so abundant that it could meet the needs of worldwide energy consumption 6,000 times over . And solar energy is easily harnessed thorough the use of photovoltaic cells that convent sunlight into electricity.In the United States alone ,more than 100,00 homes are equipped with solar electric systems in the from of solar panels or solar roof tiles .And in other the world ,including many developing countries ,the use of solar systems is growing steadily. Another alternative energy source ,which is abundant in specific geographical areas ,is geothermal power ,which creates energy by tapping heat from below the surface of the earth.Hot water and steam that are trapped in underground pools are pumped to the surface and used to run a generator ,which produces electricity geothermal energy is 50000 times more abundant than the entire known supply of fossil fuel resources and as with solar power, the technology needed to utilize geothermal energy is fairly simple. A prime example of effective geothermal use in Iceland,a region og high geothermal activity where there are over 80 percent of private homes, are heated by geothermak power
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