Saving Gaia
Saving Gaia - Join The World, Do Your Part Today

Fossil fuels are fuels made from remains of animals and plants fossilised many millions of years ago.  Examples of fossil fuel are cruel oil and natural gas.  As can be imagine, there is a limit to the amount of fossil gas.  Biofuels are fuels made from plants.  It is considered a form of renewable energy.  In principle, biofuels has zero-emission of greenhouse gas.  The plants absorb carbon dioxide from the air as they are growing, and consequently, the carbon dioxide that is released when biofuels made from plants, are burned does not represent a net addition of that greenhouse gas to the atmosphere.  Hence, in the search for replacements for fossil fuel, biofuels have gained the most political support.  One of the more practical reasons is that biofuels promise lucrative new markets for US farm products.
The Problems Created By Biofuel Production
The first-generation of biofuels consists of ethanol made from corn or sugar cane, or biodiesel made from vegetable oil.  However, these biofuels are produced by using fossil fuels, mainly natural gas, for refining.  It has created some controversy about whether biofuel is really "clean".  The bigger problem is that in many countries, food crops are being forgo in favour of biofuel plants.  This has led to shortage of food crops.

Another problem is the pollution caused by biofuel crop farming.  The production of biofuel crop, corn farming is the biggest source of pollution associated with ethanol production.  Corn requires much more fertilizer and pesticides than other biofuel feedstocks, such as soybean and perennial grasses. The fertilizer and pesticide runoffs from the U.S. Corn Belt are also poisoning the environment with nitrogen.  Nitrogen accumulation is a key factor for the creation of “dead zones” in the Gulf of Mexico and along the Atlantic Coast.

The amount of water required for ethanol is also a source of concern, particularly since shortage of potable water is fast becoming a problem in many countries.  Ethanol production plants need around three gallons of water just to produce one gallon of ethanol.  So a typical ethanol plant producing 100 million gallons of ethanol a year, would use as much water as a town of 5,000 people.
There have been calls for biofuels to be made made from “advanced” feedstocks, such as cellulosic ethanol or algae, which are believed to have a smaller environmental footprint.  The so-called second-generation biofuels are also made from plant wastes, or from purpose grown crops on land that not suitable for food production.  However, the technology to make these newer fuels is till in its infancy and it is not cost competitive yet.  So corn is likely to remain as the primary feedstock for U.S. ethanol production through 2020.
Biomass is another form of biofuel.  In principle, biomass power is considered renewable and has zero-emission of carbon dioxide.  Biomass power plants typically burn plant or tree matter to generate electricity. Critics of biomass plants are concerned that forests would be destroyed if the industry is not regulated properly.