Energy Sources for North Carolina

Fossil Fuels

• Coal, oil, and gas• Formed from fossilized remains of

prehistoric plants and animals• Provides 95% of the world's total energy

needs

How Fossil Fuels Work

• Coal is crushed to a fine dust and burned

• Oil and gas can be burned directly

• Burned fuel creates steam, which is converted to electricity

Burn fuel > heat water to make steam > steam turns turbine > turbine turns electricity generator > electrical power sent around the country

Advantages of Fossil Fuels

• “Cheap” source of energy • Large amounts of electricity can be

generated in one place using coal• Transporting oil and gas to the power

stations is easy• A fossil-fueled power station can be

built almost anywhere

Disadvantages of Fossil Fuels• Air and water pollution problems• Burning fossil fuels produce carbon dioxide,

which contributes to global warming• Burning coal produces sulphur dioxide,

which contributes to acid rain• The U.S. imports about half of its oil -- spills

are a serious problem• Mining coal can be dangerous and destroys

the landscape

Is it Renewable?

• When we've burned them all, there won’t be any more

Fossil fuels are NOT renewable

Nuclear Power

• Generated from Uranium, a radioactive metal mined in various parts of the world

• Produces 11% of the world's energy needs

• Produces huge amounts of energy from small amounts of fuel

How Nuclear Power Works

Fission makes heat > heated water makes steam > steam turns turbine > turbine turns generator > electrical power sent around the country

• Nuclear fission (splitting the nucleus of a uranium atom) releases enormous amounts of energy

• Heat generated makes steam…

Advantages of Nuclear Power

• Inexpensive to make power• Does not contribute to the

greenhouse effect• Produces huge amounts of

energy from small amounts of fuel

• Creates small amounts of waste

• Reliable energy source

Disadvantages of Nuclear Power

• Although not much waste is produced, it is very dangerous (radioactive)

• It must be sealed up and stored for thousands of years

Is it Renewable?

Nuclear energy is NOT renewable.

•Once all the Uranium has been dug up and used, there isn't any more.

Solar Power

• Power from the sun• Less than 10% of energy used in the world

is solar

• Passive solar = panels filled with coiled tubes use the Sun’s heat to directly heat water (like a garden hose left in the sun)

• Solar panels contain “photovoltaic cells” that convert sunlight to electricity

• Solar furnaces use mirrors– Concentrates the Sun’s energy to produce very high temps

How Solar Power Works

Advantages of Solar Power

• Does not produce carbon dioxide• Sunlight is free, no fuel needed• Minimal impact on the environment

Disadvantages of Solar Power

• Expensive to build• Amount of sunlight varies by time of

day, weather, season, etc.• Needs a lot of surface area for

collection

Is it Renewable?

•The Sun keeps shining, no matter how much is used for energy

Solar Power IS renewable

Wind Power

• Wind power harnesses the energy of air movement

• Wind power is an ancient form of energy – used throughout history for sailing, grinding grains, pumping water

How Wind Power Works

• The Sun heats the atmosphere unevenly, which changes air pressure

• Air moves from high pressure to low• Wind moves a propeller on top of a tall

tower, and the turning propeller generates electricity

Air moves propeller > propeller turns turbine > turbine turns electricity generator > electrical power sent around the country

Advantages of Wind Power

• Wind is free, no fuel needed• Produces no waste or greenhouse gases• The land beneath can usually still be used

for farming• Good for remote areas

Disadvantages of Wind Power• Wind is not always predictable• Suitable areas for wind farms are often near the coast, where land is expensive

• Birds can be killed• Can be noisy

Is Wind Power Renewable?

• Winds will keep blowing, no matter how much is used for energy

Wind power IS renewable

Hydropower

• Harnesses the power of falling water and converts it to electricity

• Largest source of renewable energy used in N.C.

How Hydropower

Works

• A dam is built to trap water, usually in a valley where there is an existing lake

• Water is allowed to flow through tunnels in the dam, to turn turbines and thus drive generators

Advantages of

Hydropower

• Once the dam is built, energy is virtually free

• No waste, pollution, or carbon dioxide produced

• More reliable than wind and solar • Water can be stored/released as needed• Electricity can be generated constantly

Disadvantages to Hydropower

• Dams are very expensive to build• Building a dam floods a large area

upstream, destroying habitat and homes• Finding a suitable site can be difficult as

areas are more developed• Water quality and quantity downstream

can be affected, which can damage plants/animals

Is it Renewable?

Although individual dams may not live forever, water will always move

• Hydropower IS renewable

Biomass Power

• Plant and animal waste burned as fuel– E.g., animal manure, wood, grasses, used cooking

oil, corn stalks, garbage, gases from landfills

• About 5% of U.S. energy use

Burn fuel > heat water to make steam > steam turns turbine > turbine turns electricity generator > electrical power sent around the country

Advantages of Biomass

• The fuel tends to be cheap.• Lower demand on the earth's resources.

Disadvantages of Biomass

• Can be difficult to collect enough waste• Burning fuel releases carbon dioxide• Some waste materials are not available

all year round

Is it Renewable?

We can always plant & grow more sugar cane, trees, etc., and we always make waste.

• Biomass IS renewable

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