Renewable resources are natural resources that can be replenished, such as plants, animals, wind, water, and geothermal energy. Humans use renewable resources for food, energy, and power. There are several types of renewable energy including solar energy from solar cells, wind energy from wind turbines, hydroelectric power from dams, geothermal energy from hot underground rock, and nuclear energy from splitting atoms. Each renewable energy source has advantages and disadvantages related to factors like costs, land needs, and pollution levels.

1. RENEWABLE RESOURCES8SCIENCE: Wed. Jan. 12/Thurs. Jan. 13

2. What are renewable resources?Renewable resources are natural resources that can be recycled or replaced by the environmentE.g.: Cotton plants to make clothing i.e. jeans can be planted again each yearExamplesPlants and animalsWind Geothermal Nuclear Water (hydro)

3. How do we use renewable resources?Humans use renewable resources as a source of food (plants and animals) to help us surviveWe also use renewable resources to provide energy and power Examples: Solar energy: solar cellsWind energy: wind farmsWater energy: dams

4. SOLAR ENERGYSolar energy is energy from the sunIt is trapped in solar cells and turned into electric current Sunlight hits cells covered with silicon (Si) layers, changes the light and a stream of electrons is createdSolar cells can be small and easy to useExpensive to generate largeamounts of electricity

5. WIND ENERGYElectricity can be produced on wind farmsWind turbines are placed on the land Need lots of open spaceNo pollution is produced

6. WATER ENERGYCalled hydroelectric powerElectricity created from the energy of flowing water by building damsEarth’s water cycle continually replaces the water and it is non-polluting

7. GEOTHERMAL ENERGYUsed and found in locations with lots of volcanic activityEnergy from an eruption comes from hot rock under the Earth’s surfaceThermal energy (heat energy) is used to generate electricity

8. NUCLEAR ENERGYHuge amounts of energy are stored in the nucleus of an atomWhen this nucleus is split, the energy released is used to generate electricitywater is heated by this energy and turns to steam which turns turbines to produce electricity Examples: - uranium (U)

9. Questions to consider: Which renewable energy is ‘best’?Which renewable energy type is a good alternative to burning fossil fuels (using non-renewable resources) ?Which renewable energy type produces little pollution?Which renewable energy type costs little money?Which renewable energy type requires little land and people to manage it?