module38REVIEW

In this module, we have seen that biomass and water are two important renewable energy sources. Biomass is a modern source of carbon, which was formed between a few years ago and hundreds of years ago, as opposed to fossil fuels, which contain carbon formed millions of years ago. Solid biomass includes wood, charcoal, and animal manure, all of which are relatively low-quality sources of energy and release a fair amount of particulates and other pollutants when burned. Liquid fuels include ethanol, an alcohol derived from plant material such as corn, and biodiesel, produced from vegetable oils such as soybean. Algae is another source of oil for biodiesel. Hydroelectricity is generated from the energy in water. The largest hydroelectric projects come from impounding water behind a large dam and releasing it periodically when electricity is needed. The impounded water behind a dam can promote recreational and economic opportunities but can also have numerous impacts on the environment. Water availability in a region may be somewhat variable. In the next module we will examine two continuous, nondepletable sources of renewable energy: the Sun and wind.

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Module 38 AP® Review Questions

Question 1

1. Which is NOT a form of biomass?

  1. Coal

  2. Charcoal

  3. Manure

  4. Municipal solid waste

  5. Ethanol

Question 2

2. A hydroelectric power plant’s rate of electricity generation depends on

  1. The flow rate of the water

  2. The vertical distance the water falls

  3. The amount of water behind the dam

  1. I only

  2. I and II only

  3. II only

  4. II and III only

  5. I and III only

Question 3

3. Which is true of solid biofuels?

  1. Charcoal is the primary replacement when wood is scarce.

  2. Indoor air pollution from them results in millions of deaths annually.

  3. Switchgrass is a newly developed replacement for wood.

  4. They are carbon neutral due to the net removal of forests.

  5. The primary use of manure is as a heat source in developed nations.

Question 4

4. Cellulosic ethanol is produced from

  1. corn.

  2. beets.

  3. sugarcane.

  4. switchgrass.

  5. soy.

Question 5

5. The most common method of hydroelectric generation is

  1. run-of-the-river.

  2. tidal.

  3. water impoundment.

  4. gorge dams.

  5. siltation.