Imagine living in a pollution-free city! The world needs power but the Earth’s current sources of energy are destroying our environment. Our future depends on environmentally friendly energy and Green Power explores current research into such solutions as biofuels, wind, and solar energy. This book explains - how traditional dams use gravity to spin electric turbines - how ocean tides can be used to create energy - how heat from deep inside the Earth is used by some countries to heat homes and power lights - the amazing facts about how we can improve our energy consumption today