Energy Sources

As a renewable resource, hydroelectricity is generating more attention as environmental concerns rise. What is one advantage of using this as an energy source? Hydroelectric energy –

• reservoirs can be used for irrigation of crops.
• may divert water and alter normal water flow.
• might disrupt the movements of migrating salmon.
• sometimes causes flooding in surrounding areas.

One disadvantage to using coal to produce electricity is that coal -

• forms in a short amount of time.
• is abundant over a wide area.
• is not environmentally friendly.
• is relatively quite affordable.

Natural gas is a fossil fuel formed within oil fields and coal beds. What is an advantage of using natural gas as an alternative form of energy?

• It releases relatively low emissions compared to other fossil fuels.
• The stored energy is less concentrated, so more needs to be burned.
• There is a limited supply since it is a non-renewable resource.
• It tends to be more expensive compared to other fossil fuels

A student was asked to give the disadvantages of using biomass as an energy source and stated that there are no disadvantages. Which of the following best evaluates the response of the student?

• Incorrect, because biomass is available almost everywhere since it a byproduct.
• Correct, because biomass is a renewable fuel source if the biomass is harnessed properly.
• Incorrect, because biomass is a less concentrated form of energy, making it inefficient.
• Correct, because the amount of harmful emissions released is less than other fuel sources.

What is the most significant way to decrease energy consumption in a household according to the graph provided?

• Turn off computers and other electronics when they are not in use.
• Increase the temperature of a house in warm months, and decrease it in cool months.
• Turn off lighting that is not necessary, or when the household is empty.
• Keep the refrigerator door closed as much as possible to avoid letting cold air out.