U2L4: Renewable Resources

U2L4: Renewable Resources

Pages 140-142

What are alternative, renewable sources of energy?

• More than 3/4 of the energy used in the US comes from fossil fuels

• These will eventually run out if we keep using them

• To prevent this, we could use an alternative, renewable energy source

• This would allow use to conserve, or save, fossil fuels.

Solar Energy

• Solar energy is renewable energy from the sun that can be converted into electrical energy. Solar energy is free and clean.

• However, the technologies for solar energy aren’t widely used. Also, sunlight does not fall evenly over Earth.

Hydroelectric Energy

• Energy from fast-moving rivers/water flowing downhill through dams to turn generators and produce electricity.

• It requires large volumes of water which can risk flooding.

• Flooding the land to produce reservoirs can destroy habitats, and dams can disrupt migratory paths of fish and lead to erosion.

Wind Energy

• Blowing wind causes the blades of wind turbines to turn. This turns a generator & produces electricity.

• Wind energy doesn’t produce any pollution.

• However, it depends on strong winds and can harm birds that fly too close to the blades. It can also be very loud

Geothermal Energy

• Geothermal energy is extracted from heat stored within Earth.

• It is available near hot springs, geysers, or active volcanoes.

• Water or steam is heated by geothermal energy & then used to generate electricity.

• Found only in specific areas on Earth - some of which are in national parks (which means we can't access it).

Energy from Burning Biomass

• Biomass includes living or recently dead organic material that can be used as fuel.

• Examples are trees, crops, & decaying organic matter.

• Biomass materials are burned directly or converted into fuels.

• Burning biomass releases carbon dioxide.