Energy from Water: Hydroelectric, Tidal, and Wave Power
Contents Types of Energy Moving Water Renewable Energy Howa Dam Works 10 Where in the World 12 Small Solutions 14 16 18 Environmental Impact Benefits of Hydroelectricity Wave Power Waves For and Against Tidal Power 20 22 24 Tidal Pros and Cons 26 Power Up 28 Glossary 30 Learning lore Index 32
UDES of Energy A skier stands at the top of a mountain ready to begin the descent Being at the top of a steep slope gives her potential energy which is the energy an object has because of its position not its motion Once she uses her muscles to push off Earth's gravity will pull her down the slope Her potential energy turns into kinetic energy or energy from movement We use energy all the time in our daily lives Some of the energy we use harnesses the power of kinetic energy Blowing wind and flowing water are forms of kinetic energy that can be converted into electrical energy This electricity can then be used for many different things from charging a cell phone to powering a car We get our energy from other sources too We burn fuels such as coal or oil We generate heat energy from chemical reactions We use panels to collect energy from sunlight Hydroelectric power which is electricity generated from moving water is one of the cleanest energy sources in use However no energy source is perfect some create pollution some are too expensive and some contribute to the warming of Earth and global climate change This surfer depends on the kinetic energy of the wind to push the ocean's water into
Using Energy World Electricity Generation in 2012 5 22 5 Coal Natural gas Nuclear Earth's energy needs are increasing all the time The planet s population is increasing and each person uses more energy than they did a few decades ago Lifestyles have changed We have become used to traveling by car or airplane and depend on appliances and gadgets that make our daily lives easier These all require power in some form How can we continue to meet all of our energy demands Our challenge for the future is to find clean low cost sources of energy that are sustainable This means living in a way that conserves and efficiently uses natural resources 10 9 Hydroelectric Other 40 4 16 2 5 Hydroelectric power already makes up a si ficant percentage of the world's electricity supply R E WI N D For hundreds of years people have used the energy of the wind Sun and water in various forms For example the wind can fill the sails of a ship and push it forward or turn the blades of a windmill that grinds grain Today we harness their power to generate electricity Electricity lights our homes and powers our devices Do you think this is a better use of these natural forms of energy Give reasons for your
