We absolutely need energy. RECENTLY, we always use it. Even, we can’t live without it. Imagine a live without televisions, lamps, refrigerators, cars. Of course, we don’t want that happen. But, do we know about the source of our energy consumption? Most of our energy consumption still uses fossil fuel. In 2006, about 18% of global final energy consumption came from renewable energy, so 82% of global final energy consumption use non-renewable energy that is fossil fuel. Actually, it provides valuable service, but the side effect of using them cause many of problem. One of the problems is non-renewable. It is limited in supply and one day will deplete. Fossil fuel formed from plants and animals that live hundred of million years ago and became buried under the surface of earth where they transformed into combustible material which always we use. We have to wait until hundred of million years to get new fossil fuel. At our rate of consumption, these fuels cannot occur fast enough to meet our current or future energy demands. Nobody really knows when the last drop of oil, lump of coal or cubic foot of natural gas. Some scientists say that fossil fuel will be depleted within 100-120 years. By the year 2020, world energy consumption is projected to increase by 50 %. If we still use fossil fuel, there is a problem. The next problem is chemically changing. In order to convert them into usable energy require chemical changing to extract the energy within. To extract the energy contained in these, we have to burn them. When we burn them, there is a chemical changing. The result of this burning is water vapor, ash, and carbon dioxide which are pollutant. These materials can pollute our environment. Imagine a planet so polluted that the smog is in the air so badly so we can not see very far, the lakes and streams are poisoned and the land is so bad. One day this may be a real if we do not do something to change our energy consumption, if we still use the non renewable energy. Besides, we destroy ecosystems while mining it. Fossil fuel mining and oil production has caused irreparable damage to our environment. So, it is a time where we have to think about it. One of the best ways is using renewable energy. Renewable energy is the energy which comes from renewable resources. Essentially, these renewable energy sources create their own energy. There’s more than enough renewable energy sources to supply all of the world’s energy needs forever; however, the challenge is to develop the capability to effectively and economically capture, store and use the energy when needed. There are many of natural energy such as Biofuel, Biomass, Geothermal, Hydropower, Solar power, Tidal power, Wave power, Wind power. Sun, wind and water are perfect energy sources. They are non-polluting, renewable and efficient. Wind power is growing at the rate of 30 percent annually, with a worldwide installed capacity of 121,000 megawatts (MW) in 2008, [ 3 ] and is widely used in European countries and the United States. Solar energy is having the most immediate impact on home energy needs, and is expected to provide the energy needs for one billion people by the middle of this century. Homes can be fitted with solar panels, such as the ones pictured above. The sun also provides enough energy that can be stored for use long after the sun sets and even during extended cloudy periods. But making it available is much easier said than done. The technology is pretty much ready for many business and consumer applications, but it would be way too expensive to replace the current energy infrastructure used for fossil fuel energy. According to the European Photovoltaic Industry Association , solar power could provide energy for more than one billion people by 2020 and 26% percent of global energy needs by 2040.