Alternative Energy Sources

Many resources go towards making

electricity.

http://www.tva.gov/power/images/coalart.png

Most energy used today comes from

fossil fuels.

Fossil fuels come from the remains

of once living things.

They include: coal, oil (petroleum), and natural gas.

While fossil fuels are relatively cheap, we need alternatives to them b/c they are:

Nonrenewable

Cause pollution

And have to be mined

Some Alternatives include:• Wind energy• Geothermal energy• Nuclear energy• Biomass• Hydroelectric• Solar

*No energy source is perfect, but some are better than others b/c they are better for the environment and they are renewable.

Alternative Energy Source

Reasons to use it Reasons to not use itDescription of how it works

Where is it currently being used?

How often is it being used?

Solar Power

Non air polluting-Renewable-Sunlight's free-Sun makes lots of energy-Good in remote areas

Only good where its sunny-expensive-not very efficient- no way to store energy-unreliable

radiation from the sun is turned it into energy

 Sunny climates(Germany and Italy)

0.2% 1%

Wind Energy

Inexpensive (wind is free)-Non air polluting-Renewable-Good in remote areas-land can be used for other things too

 unreliable-need room-ugly- may kill birds-can be noisy-

wind turn the turbines to generate electricity

 Places w/ strong, steady wind- usually near coast or rounded hilltops(Denmark, Portugal, Spain)

 0.51% 9%

Hydroelectric Energy

 Inexpensive-renewable-can make lots of energy

 Expensive to build-flooding behind dam- bad for wildlife-Only works on big rivers

Building a dam, flowing water turns turbine

 Any river where a dam can be built and a reservoir will form (China)

  35%

Geothermal Energy

 Non air polluting-renewable-uses little land-inexpensive-no fuel needed

 Limited availability-may be unreliable-sometimes harmful gasses/minerals come up

Pump water into crust, heat turns it to steam

 Where crust is warmed by tectonics (Iceland, Italy, Japan,..)

0.12% 5%

Biomass Energy

Tend to be cheap-Renewable-can use waste planet material

 Not very efficient-Requires space to grow-may release greenhouse gasses-uses land which could be growing food

Generally burn plant materials to heat the water

Anywhere plants can grow

0.28% 26%

Nuclear Energy

 Inexpensive-Non air polluting-makes lots of energy from small amount of fuel-reliable

Nonrenewable- waste is very dangerous and must be safely stored for 1000s of years-NONrenewable

heat from splitting atoms turns water to steam

Pretty much everywhere434 operable reactors world wide

2.7% 9%