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AP Environmental Science

Mr. Grant

Lesson 97

Bioenergy

&

Hydroelectric Power

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Objectives:

• Define the term biomass energy.

• Describe the major sources, scale, and impacts of bioenergy.

• Describe the scale, methods, and impacts of hydroelectric power

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Define the terms biomass energy.

Biomass Energy

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Describe the major sources, scale, and impacts of biomass energy

• Fuelwood remains the major source od biomass energy today, especially in developing nations.

• Biofuels, including ethanol and biodiesel, are used to power automobiles…- Some crops are grown specifically for this purpose, and waste oils are

also used.

• Biomass is used to generate electrical power…- Sources include special crops as well as waste products from agriculture

and forestry.

• Biomass energy, theoretically, adds no net carbon to the atmosphere and can use waste efficiently, but…- Harvesting of wood can lead to deforestation, and…

- Growing crops solely for fuel production is inefficient and ecologically damaging.

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Biomass energy

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Biomass sources are widely used

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Biomass can be overharvested

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New biomass strategies

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Biofuels can power automobiles

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Cars can run on ethanol

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Biodiesel is produced from vegetable oil

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Biopower generates electricity

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Biomass energy brings benefits

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Drawbacks of biomass energy

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Describe the scale, methods, and impacts of hydroelectric power.

• Hydroelectric power is generated when water from a river runs through a powerhouse and turns turbines.

• Dams and reservoirs and run-of-river systems are alternative approaches.

• Hydropower produces little air pollution, but dams and reservoirs can greatly alter riverine ecology and local economies.

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Hydroelectric power

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A typical dam

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A run-of-river system

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Hydroelectric power is widely used

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Hydropower is clean and renewable

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Hydropower has negative

impacts

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Hydropower may not expand much more