1. Alternative Energy

2. Problems with Fossil Fuels
Nonrenewable
Combustion of organic molecules creates pollution and releases carbon dioxide, which is a greenhouse gas. Increasing levels of carbon dioxide may lead to global warming.

3. Biomass
Energy produced from burning wood, crops, manure, and some garbage.
Pros: renewable energy source; no pollutants such as sulfur that can cause acid rain
Cons: CO2 emissions (although not as much as fossil fuels)

5. Wind Power
Wind is created when air over land is warmed; the warm air rises and cooler air rushes in to take its place (powered by the sun).
Windmills turn turbines which generate electricity.
Pros: no pollution, renewable source
Cons: need a back-up source when the wind isn’t blowing, start up is costly, birds can be harmed by the windmills

6. Hydropower Most common renewable energy source used
Running water turns turbines to generate electricity
Pros: no pollution, free source of energy, plants already existing
Cons: ruins natural habitats (affects spawning)

7. Solar Power
Solar energy can be used directly to heat things such as homes and swimming pools.
Photovoltaic cells (solar cells) convert the sun’s energy into electricity; electricity can also be produced indirectly by heating water to create steam that turns turbines.
Pros: inexhaustible (and free) source of energy
Cons: Start-up is expensive, and solar cells tend to be inefficient.

8. Geothermal Power
Heat from the interior of the Earth is used to release steam, turning turbines that generate electricity
Pros: less pollution than fossil fuels, renewable energy source
Cons: only a few locations available for this; some impact to environment

9. Nuclear Power
A specific type of uranium is mined and refined; the atoms are split in a fission chain reaction, releasing huge amounts of energy.
The energy is used to heat water, creating steam that turns turbines, generating electricity
Pros: no greenhouse emissions, provides large amounts of energy
Cons: nonrenewable, radioactive waste is a byproduct, possible dangers to nearby communities

11. Alternatives to Gasoline and Diesel

12. Ethanol
Ethanol is grain alcohol made from fermenting the sugars in corn or sugar cane; it can even be made from corn stalks and wood waste.
Pros: fewer greenhouse gas emissions; renewable resource; no need to import
Con: Not as efficient as gasoline, so your car cannot go as far on E85 as it can on gasoline.
E10 – 10% ethanol and 90% gasoline (all post-1980 cars can run on this)
E85 – 85% ethanol and 15% gasoline (need flex fuel vehicle to run on this)

13. Butanol
Pros: Similar to ethanol in the way it’s made, but provides more energy and is safer to handle than either ethanol, gasoline, or hydrogen; reduces emissions.
More expensive to produce.

14. Biodiesel Fuel
Biodiesel is made from vegetable oils (mostly soybean), animal fats, and used restaurant grease.
Can be mixed with regular diesel fuel.
Pros: better engine performance, don’t need special vehicle, fewer greenhouse gas emissions; renewable resource; no need to import
Cons: more expensive than regular diesel; slightly lower fuel efficiency

15. Hydrogen Fuel Cell
Although hydrogen is the most abundant element in the universe, on Earth it is bonded to other atoms, and these molecules need to be split to produce pure hydrogen (requires energy).
Pros: the only byproduct is heat and water – NO POLLUTION! (except the energy needed to produce the hydrogen fuel)
Cons: fuel cells expensive, will need whole new infrastructure to store and deliver hydrogen fuel