Pumping gas is an excellent time for existential contemplation. Next time you're topping off the tank, think about where that gasoline came from. Saudi Arabia? No, let's go back even farther: Your gasoline began its life 300 million years ago as a leaf of ancient seaweed or a prehistoric shark with a heart condition. When that shark died and that seaweed shriveled, they decomposed on the ocean floor. Over the millennia, as more and more organic matter settled on top of the shark and seaweed, the pressure and heat converted the carbon from those dead creatures into the viscous goo we call crude oil.
That's where Saudi Arabia comes in. The ancient crude is pumped from the earth, shipped by supertanker to a refinery in Texas and converted to gasoline (and diesel fuel and jet fuel and the occasional vat of Vaseline).
As you are contemplating this 300-million-year production cycle, consider the energy that was required to crush that carbon into crude, and then the fuel required to dig the oil wells, pump the stuff, ship it halfway across the world, refine it, load it onto trains, then trucks, finally to arrive at your local filling station. There must be more direct and energy efficient and environmentally sound ways to transform carbon-based matter into fuel? There are, and they're called biofuels.
Biofuels are any form of energy derived from a plant source. The most common biofuels are ethanol, an alcohol fuel made from fermenting a sugary source material like corn or sugar cane, and biodiesel, a diesel fuel made from vegetable oils and fats rather than crude oil. When the feedstock for biofuels is grown and harvested in a responsible, sustainable way, the benefits of biofuels impact more than the price at the pump. Biofuels have to potential to reduce pollution, reduce global poverty, and convert millions of tons of waste into clean-burning energy.
Here is our list of the five ingenious ways that responsibly produced biofuels can benefit everyone, starting with a switch from corn-based ethanol to "grassoline."
Ethanol production has sparked a hot debate among environmental scientists and farmers. It's true that ethanol burns cleaner than conventional gasoline, emitting less carbon dioxide and benzene into the air. It's also true that corn and other plants used as ethanol feedstock absorb atmospheric carbon dioxide in their growth stage, greatly reducing carbon dioxide levels over the entire fuel life cycle [source: U.S. Department of Energy]. But the dependence on corn as an ethanol feedstock in the United States has created problems, both with the food supply and fossil fuel consumption.
Humans directly consume only two out of every 10 ears of corn grown in the U.S., either as fresh corn, corn syrup, corn meal or other corn derivatives. The other eight ears traditionally became feed for livestock like cows, pigs and chickens, but that was before the ethanol boom. Thanks in part to government subsidies, more corn was grown for ethanol from August 2011 to July 2012 than for livestock [source: Lott]. That was a first in American farming history. In a year when drought conditions lowered total corn yield, critics blame ethanol production for even higher food prices [source: McDonald].
Corn and soybeans, another popular ethanol feedstock, also require large amounts of fossil fuel energy to produce. Tractors burn up their fair share of fossil fuels, but the biggest culprit is synthetic fertilizer. Nitrogen fertilizer, for example, requires 1.5 tons (1360.7 kilograms) of fossil fuels -- usually coal and natural gas -- to produce one ton (907.18 kilograms) of nitrogen [source: Oliver].
Thankfully, researchers and farmers have identified a number of non-food sources of ethanol feedstock that can grow just about anywhere without any additional fertilizers. In the U.S., the best options are tall grasses like switchgrass and miscanthus. These grasses grow more than 10 feet (3.05 meters) high in thick strands, and they're perennials, which means they can be harvested in the fall and grow back in the spring. Fewer plantings means less fossil fuel burnt in the tractor. In tropical climates like Hawaii and Southeast Asia, researchers are experimenting with bana grass, sweet sorghum and an inedible oil nut called jatropha [source: Smith].
These grasses can grow in poor soils with little irrigation or fertilizer input. And they pack a biomass punch. According to tests by the Argonne National Laboratory, switchgrass has an energy output ratio of 1 to 10, meaning every unit of energy consumed to produce switchgrass ethanol results in 10 units of available energy. Corn ethanol, on the other hand, produces only 1.36 units of energy output for every unit of energy input [source: Wang].
The switch to "grassoline" is ingenious because it doesn't compete with existing food crops, can be grown on marginal land, doesn't rely on synthetic fertilizers and produces a far greater amount of energy per unit of biomass. That helps to keep food prices down, fuel costs down, and pollution levels low -- a win for everyone!
Starting as early as the 1950s, alternative energy researchers have had their eyes on algae [source: Keune]. Mature algae -- that slimy green goo also known as pond scum -- are rich with lipids, a type of molecule that includes fats. Those lipids can be extracted and turned into biodiesel. The remaining dry algal matter can be fermented and processed into ethanol [source: Haag]. Two fuels for the price of one!
Algae need three things to grow: water, sunlight and carbon dioxide. Otherwise, they're not very picky. Algae can grow in salt or fresh water, even in wastewater from sewage treatment facilities or dairy farms. The key to growing great algae is lots of available carbon dioxide in the water. Naturally occurring ponds don't usually contain enough carbon dioxide to maintain healthy growth rates, but researchers have figured out an ingenious solution: redirecting carbon dioxideemissions from coal-fired power plants into the algal ponds. Not only does algal biodiesel burn cleaner than conventional gas, but it eats up coal emissions.
Under the right conditions, algal colonies can double in mass overnight, and an impressive 50 percent of that mass is oil. To compare, the second best oil-producing plant is the oil-palm tree, which is only 20 percent oil [source: Haag]. The U.S. government has invested tens of millions of dollars to help bring algal fuels to market, but current production methods still cost a prohibitive $8 a gallon at the pump. The hope is that with further investment by the United States military and energy giants like Exxon Mobil and Chevron, algae will become both an environmental and economic superfuel.
The U.S. military is the world's largest gas guzzler, buying and burning through more than 8 billion gallons of fuel per year [source: National Energy Technology Laboratory]. Jet fuel is a particularly expensive resource and the military is always looking for ways to cut the cost of maintaining its airborne fleet. One exciting possibility is the increased use of biofuels in the jet fuel mix.
During World War II, German scientists developed a process of making liquid fuel from coal. Known as Fischer-Tropsch (F-T) fuels, they can be made from coal, natural gas or biomass [source: Ryan]. The U.S. military is particularly interested in biomass as a fuel source because it decreases reliance on foreign oil, thereby increasing energy security in the event of an international crisis.
But the focus on biofuels is about more than energy security or "greening up" the military. It's also a smart business decision. In a 2012 press conference, Assistant Secretary of the Air Force Terry Yonkers explained that military testing shows that biofuels burn cleaner and cooler in jet engines. That increases overall engine life by a factor of ten, greatly reducing repair and replacement costs [source: Ryan].
Another benefit of biofuels is that they have less mass than fossil fuels, meaning that bio-based jet fuel weighs less than conventional jet fuel. This could have big implications for commercial aircraft, where the weight of the airplane is reflected in ticket prices. A greener, more secure military plus cheaper flights to Cleveland? Another biofuel win for everyone.
Slightly less than half of the world's population lives in rural areas, but they make up 70 percent of the world's poor [source: The World Bank]. For decades, the plight of poor rural farmers has been exacerbated by low food prices. The global market for food staples like wheat and corn was dominated by the United States and Europe, where government subsidies kept prices unnaturally low. A country like Mexico, which used to feed itself on its own corn, now imports 12 million tons (10.88 billion kilograms) a year from the U.S., where corn prices are lower [source: Rodriguez].
Oil is the same. Of the world's 47 poorest countries, 38 import more oil than they produce domestically and 25 of those 38 countries import every drop of oil they consume [source: Worldwatch Institute]. With an overreliance on both foreign-grown food and foreign oil, the rural poor in developing nations are dangerously exposed to price spikes. When food and oil prices go up, as they have dramatically in recent years, they suffer the consequences without any of the benefits.
Homegrown biofuels have the potential to reverse the poverty rate in developing nations. Think of the hundreds of millions of farmers who can barely subsist on the market price of their food crops. By growing ethanol and biodiesel feedstock, they will receive a fair price for a hot commodity. At the same time, energy entrepreneurs in their same country can build the biofuels infrastructure to generate homegrown energy. A 2010 report from the International Food Policy Research Institute concluded that increased biofuel production in countries like Tanzania and Mozambique could decrease the poverty rate in those countries by 5 percent by 2020 [source: Arndt et al].
Lower energy costs, better wages and reduced rural poverty -- another biofuel win for everyone.
The average American generates 4.43 pounds (2 kilograms) of garbage every day. As a nation, we tossed out roughly 250 million tons (227 billion kilograms) of trash in 2010, from food waste to construction debris to outdated iPhones [source: EPA]. What if we could divert all of that waste from the landfill and convert it into usable energy? Doc Brown did it in "Back to the Future" -- feeding his DeLorean's cold fusion reactor with banana peels and beer -- and thanks to a process called gasification, so can we.
Gasification uses heat and pressure to crack the molecular compounds of almost any carbon-based material into a substance called synthetic gas, or syngas. All around the world, cities are replacing their landfills with gasification plants. In Edmonton, the capital of the Canadian province of Alberta, the city is building a facility that will convert 100,000 tons (90 million kilograms) of municipal waste into 9.5 million gallons (35,961 cubic liters) of biofuel annually [source: City of Edmonton].
Inside the Edmonton facility, scheduled to open in 2013, municipal waste (garbage) will be sorted by type: compostable organic waste, recyclable material and waste products that would normally be sent to the landfill. Those leftovers will be shredded into a fine pulp and fed into the gasifier, where incredible heat — not fire — liquefies the material into carbon monoxide (CO) and hydrogen (H2), the major elements of syngas. The syngas will then pass through a catalytic converter where the molecules are rearranged to form ethanol, a standard biofuel, and methanol [source: Edmonton Biofuels].
From California to Finland, more of these plants are popping up to process wood-based waste and plain old garbage. Could Doc's DeLorean be far off? Well, yes. But when millions of tons of trash become millions of gallons of gas, that's another biofuel win for everyone.
For lots more information on biofuel, grassoline, garbage cars and other alternative fuels, explore the related links on the next page.
How much do you know about sweet sorghum? Keep reading to learn about Sweet Sorghum: The Sweetest Fuel You'll Ever Taste!
Author's Note: 5 Ways Responsibly Produced Biofuels Benefit Everyone
It was inspiring to research this article and learn about all of the innovative energy technologies being implemented around the world. It's easy to get pessimistic about fossil fuels and climate change and gas prices, but it's exciting to know that there are smart minds at work developing the technologies that can turn wild grass and trash into fuel for my Ford. I hope that all of the potential benefits of a global switch to biofuels are realized in my lifetime. It would make this gas-guzzler proud.
- Arndt, Channing; Pauw, Carl; Thurlow, James. International Food Policy Research Institute. "Biofuels and Economic Development in Tanzania." April 2010 (August 30, 2012) http://www.ifpri.org/sites/default/files/publications/ifpridp00966.pdf
- City of Edmonton. "Waste-to-Biofuels Facility" (August 30, 2012) http://www.edmonton.ca/for_residents/garbage_recycling/biofuels-facility.aspx
- Edmonton Biofuels. "Technology" (August 30, 2012) http://www.edmontonbiofuels.ca/technology.htm?yams_lang=en
- Haag, Amanda Leigh. Popular Mechanics. "Pond-Powered Biofuels: Turning Algae into America's New Energy." March 29, 2007 (August 30, 2012) http://www.popularmechanics.com/science/energy/biofuel/4213775
- Keune, Nash. National Review Online. "Algae: Fuel of the Future?" March 8, 2012 (August 30, 2012) http://www.nationalreview.com/articles/292913/algae-fuel-future-nash-keune
- Lott, Melissa C. Scientific American. "The U.S. Now Uses More Corn for Fuel Than for Feed." October 7, 2011 (August 30, 2012) http://blogs.scientificamerican.com/plugged-in/2011/10/07/the-u-s-now-uses-more-corn-for-fuel-than-for-feed/
- McDonald, Kay. CNN. "Paying more for food? Blame the ethanol mandate." August 20, 2012 (August 30, 2012) http://www.cnn.com/2012/08/20/opinion/mcdonald-corn-ethanol/index.html
- National Energy Technology Laboratory. "Fischer-Tropsch Fuels" (August 30, 2012) http://www.netl.doe.gov/publications/factsheets/rd/R&D089.pdf
- Oliver, Rachel. CNN. "All About: Food and Fossil Fuels." March 17, 2008 (August 30, 2012) http://edition.cnn.com/2008/WORLD/asiapcf/03/16/eco.food.miles/
- Rodriguez, Carlos Manuel. Bloomberg. Mexico Corn Imports to Surge to Record As Output Outlook Cut." August 12, 2011 (August 30, 2012) http://www.bloomberg.com/news/2011-08-12/mexico-corn-imports-to-surge-to-record-as-output-outlook-cut-2-.html
- Ryan, Margaret. AOL Energy. "Biofuels: Better for Airplanes, Too?" June 13, 2012 (August 30, 2012) http://energy.aol.com/2012/06/13/biofuels-better-for-airplanes-too/
- Smith, Dave. Big Island Now. "UH Gets Federal Grant for Biofuel Research." August 3, 2012 (August 30, 2012) http://bigislandnow.com/2012/08/03/uh-gets-federal-grant-for-biofuel-research/
- U.S. Department of Energy. Alternative Fuels Data Center. "Ethanol Benefits and Considerations" (August 30, 2012) http://www.afdc.energy.gov/fuels/ethanol_benefits.html
- U.S. Environmental Protection Agency. "Municipal Solid Waste Generation, Recycling and Disposal in the United States: Facts and Figures for 2010" (August 30, 2012)http://www.epa.gov/osw/nonhaz/municipal/pubs/msw_2010_rev_factsheet.pdf
- Wang, Michael. Center for Transportation Research. "Energy and Greenhouse Gas Emissions Impacts of Fuel Ethanol." August 23, 2005 (August 30, 2012) http://www.oregon.gov/energy/RENEW/Biomass/docs/FORUM/NCGA_Ethanol_Meeting_050823.ppt
- The World Bank. "Agriculture and Rural Development" (August 30, 2012) http://data.worldbank.org/topic/agriculture-and-rural-development
- Worldwatch Institute. "Food and Fuel: Biofuels Could Benefit World's Undernourished" (August 30, 2012) http://www.worldwatch.org/node/5300