1. Alternate Energy Sources 4.2

2. Hydroelectric Power The power generated by falling water.

3. Geothermal Energy Energy that can be extracted from Earth’s internal heat, for example, natural steam used for power generation.

4. Key Concept What are the advantages of using solar energy? Solar energy has two advantages: the fuel is free, and it’s non-polution.

5. Key Concept How do nuclear power plants use nuclear fission to produce energy? In nuclear fission, the nuclei of heavy atoms such as uranium-235 are bombarded with neutrons. The uranium nuclei then split into smaller nuclei and emit neutrons and heat energy.

6. Key Concept What is wind power’s potential for providing energy in the future? Some experts estimate that in the next 50 to 60 years, wind power could meet between 5 to 10 percent of the country’s demand for electricity.

7. Key Concept How do hydroelectric power, geothermal energy, and tidal power contribute to our energy resources? Hydroelectric power contributes by releasing water through a dam, Geothermal power contributes by using hot water to turn turbines, Tidal power contributes by generating energy from a bay’s water flow.