Look around. Are your lights on？ Is your computer running？ Electricity（电） makes them work. Electricity is a kind of energy（能源）.
　　We use energy every day. We put gasoline（汽油） in our cars. We use natural gas（天然气） in the kitchen to cook food. Where does this energy come from？
　　Renewable（可再生的） energy comes from wind， water， sunlight， plants and so on（等等）. They won’t run out（用完，耗尽）. They are cleaner（更洁净的）. People used water and wind to run（运转） mills（磨坊） hundreds of（数百的） years ago. Now we use wind and sunlight to make electricity. More and more buildings are using solar power（太阳能） too.
　　Most of energy comes from fossil fuels（化石燃料）. Coal（煤）， natural gas（天然汽） and petroleum（石油） are called fossil fuels. They come from deep underground（地下）. They are millions of（数百万） years old.
　　Some factories burn（燃烧） coal to make electricity. Some factories use petroleum to make gas. But burning fossil fuels is harmful（有害的） to our environment（环境）. And fossil fuels will run out one day. So we call them non-renewable energy（不可再生能源）. Most people use energy from fossil fuels.
　　新能源汽车
　　People are finding new ways to save（节省） and make energy all over the world. They invent（发明） electric（电动的） and solar-powered（太阳能的） cars.
　　Plants can change（变换） sunlight into useful energy. That makes them grow！ US scientists invented a solar cell（太阳能电池） powered by spinach（菠菜）.
　　節省能源
　　● Turn off lights and the TV when you’re done with them.
　　● Recycle（循环使用） paper， plastic， glass and cans（金属罐）.
　　● Walk or ride a bike instead of（代替） taking a car.
　　● Don’t leave the water running when you brush your teeth or wash your hands.
　　● Use both sides of a piece of paper.
　　● Talk to your family and friends about saving energy.