No longer the stuff of science fiction, the future is now when it comes to green energy. Test your biofuel and energy crop IQ with this electrifying quiz.
Ethanol and methanol are biofuels created when carbohydrates from various plants are distilled into alcohol. Natural gas is a fossil fuel.
Henry Ford was a huge proponent of ethanol as a source of fuel. He designed the Model T's engine to run on gasoline, ethanol or both.
The world's landfills are huge sources of methane gas, which is produced when bacteria breaks down organic materials, such as yard and food waste. Gas recovery systems capture methane and use the gas to generate electricity.
Refineries can turn starchy plants, such as corn, sugar beet and sugar cane into ethanol. Methanol is made from wood, butanol is made generally from farm waste.
Wood easily outdistances cotton and soybean as a major energy crop. Millions around the world use wood as a source of fuel. Wood is also used in biomass-fired heating and electricity generating plants.
After the energy crisis of the 1970s, Brazil stepped up its production of ethanol from sugar cane. By the end of the 1980s, most Brazilians drove ethanol-powered vehicles.
Methanol distilled from wood was once a popular fuel. Today, most methanol is made from natural gas.
Because ethanol was a product of fermentation, the government considered it a liquor. As such, the feds banned ethanol when Prohibition began in 1920. However, people could sell ethanol if it was spiked with poison.
When distilled from a bushel of corn, butanol generates 24 percent more energy than ethanol.
Some scientists believe that 43,000 square feet of algae could one day produce more than 3,500 gallons of biodiesel each year. With water covering more than 70 percent of the planet, that's a lot of biodiesel.
In 1862, American inventor named Samuel Morey built the first engine that ran on ethanol and turpentine.
As of 2009, Iowa was the main producer of ethanol in the United States, growing more than 3.2 billion bushels of corn for use as ethanol. Nebraska was the second largest ethanol producer. Montana and Minnesota didn't make the cut.
Butanol is high in hydrogen atoms. Those atoms can be easily and cheaply recovered during the distillation process and used in fuel cells.
Not only can you mash or bake a potato, but you can convert the tuber into a battery. Scientists at Hebrew University say potatoes could provide a cheap source of electricity in rural regions.
India has more than 2.5 million biogas digesters, which use cow dung as a source of energy. Out of 100,000 dairy farms in the Untied States, only 62 use biogas digesters.
According to the University of Connecticut, Americans grew 3.4 billion bushels of soybeans in 2009, which had the potential to produce 5.1 billion gallons of biodiesel.
Photosynthesis is the process by which green plants turn carbon dioxide and water into carbohydrates and oxygen, using light energy trapped by chlorophyll.
The United States led the way in ethanol production in 2009, producing 10.6 billion gallons. Brazil was second, producing about 8 billion gallons.
Bacteria and yeast break down long strings of sugar molecules into alcohol.
Californians use on average 900 million gallons of ethanol each year.