1. Renewable Energy Resources13
Renewable Energy Resources
Photo © Borut Trdina/iStockphoto

2. 13.2 What Are Sources of Renewable Energy?
Energy that is naturally replenished and that comes from the sun, flowing water, wind, Earth’s interior heat, biomass
Renewable energy will be cheaper if we eliminate:
Inequitable subsidies
Inaccurate prices
Artificially low pricing of nonrenewable energy

3. Hydropower as a Renewable Energy Resource
We can use water flowing over dams, tidal flows, and ocean waves to generate electricity.
However, environmental concerns and limited availability of suitable sites may limit the use of these energy resources.

4. We Can Produce Electricity from Falling and Flowing Water
Hydropower
Uses kinetic energy of moving water
Indirect form of solar energy
World’s leading renewable energy source used to produce electricity, least expensive
Hydropower plant
Water from dam reservoir flows, turns turbines that spin generators
Micro-hydropower generators: floating turbines

5. We Can Use Tides and Waves to Produce Electricity
Produce electricity from flowing water
Ocean tides and waves in coastal bays and estuaries
Power systems are limited
Few suitable sites
High costs
Equipment damaged by storms and corrosion

6. Wind Power as a Renewable Energy Resource
Wind power is the world’s second-fastest growing source of electricity after solar cells.
When we include the environmental costs of using energy resources in their market prices, wind power is the least expensive and least polluting way to produce electricity.

7. Using Wind to Produce Electricity Is an Important Step Toward Sustainability
Tall, long-blade turbines can extract more energy from the wind.
Rapidly growing power source
United States, Europe, and China
Future is offshore wind farms
Wind power has potential to produce 40 times the electricity currently used worldwide.

8. Case Study: The Potential for Wind Power in the United States
Wind energy—wind farms convert to electrical energy
Wind power is inexhaustible.
Could meet electricity needs of the lower 48 states
Texas and California are top producers
What do you know about renewable energy options available in your community?

9. Wind Power
Wind Power: Wind turbines convert the kinetic energy in wind to electricity. Wind power is an indirect form of solar energy.

10. Advantages and Disadvantages of Wind Power
Abundant, widely distributed, inexhaustible
High net energy
Low electricity cost
Nonpolluting
Disadvantages
Largest potential areas are usually rural
Need backup power source on calm days
May be considered noisy, eyesore