Can Biomass Fuel Save the Future?
Written By: S.C. Ringgenberg
Using domestically-produced biomass for fuel is seen by many scientists and futurists as a promising method for weaning America from importing foreign oil. What is biomass, exactly?
What is Biomass Fuel
Chemically, biomass is made up of carbon, hydrogen and oxygen. Most biomass energy is captured from organic garbage, wood waste, human and animal sewage, landfill gasses, alcohol and even algae.
Alcohol or methanol is generally made from corn or sugar cane, but can also be derived from switch grass, rice husks, wood waste from harvesting and processing trees, or more exotic plants such as miscanthus, a sugar cane relative that has been used in Southeast Asia for centuries for thatching roofs and making paper. Miscanthus has attracted the attention of the Energy Biosciences Institute at Berkley because it has many attractive qualities as a potential fuel source. For instance, one acre of miscanthus will produce 20 dry tons of usable fuel without irrigating the land it's grown on, or using fertilizer (generally derived from petrochemicals) or any other agrichemicals to help it thrive.
Biomass Fuels in the News
Last year NPR ran a story entitled: "Plants The Fuel of The Future," and in that story, Dr. Christopher Summerville, Director of the Energy Biosciences Institute, discussing the potential of biofuels was quoted as saying: "...this is something that works and just needs to work a bit better in order to make it compete with fossil fuels."In the same story, Dr. Paul Willems, the Technology Vice President for Energy Biosciences, BP commented: "If biofuels (are) going to become a big part of our company in the long run, then our view is that the only way that can be the case is that if biofuels are done in a sustainable way thatÉclearly is good for greenhouse gas and climate change, but is also good for the environment and land use..."
Pros and Cons of Biomass Fuel
Biofuels derived from plants certainly presents some interesting opportunities for the future, but plant-based biofuels are not exactly a silver bullet for America's energy needs. For one thing, if you grow plants as a fuel source, then a huge amount of farmland would have to be allocated for this purpose to create any meaningful amount of fuel. This could have an enormous impact on the total area of farmland available for food crops. Farmers who grow corn for ethanol have begun encountering resistance from environmental activists and even some politicians because they are using a food crop to make ethanol, a gasoline additive, at time when famine is a widespread problem throughout the African continent and parts of Asia.
The same arguments can be made against growing a food crop like soybeans to produce biodiesel, though used soy oil can be economically recycled to produce inexpensive biodiesel. An article on the benefits of using soy biodiesel made this cogent argument: "Soy biodiesel is better for the environment because it is made from renewable resources and has lower emissions compared to petroleum diesel. The use of biodiesel in a conventional diesel engine results in substantial reduction of unburned hydrocarbons, carbon monoxide, and soot. The use of biodiesel does not increase the CO2 level in the atmosphere, since growing soybeans consumes also CO2. Biodiesel is also more biodegradable than conventional diesel. Studies at the University of Idaho have illustrated biodiesel degraded for 95 percent after 28 days compared to 40 percent for diesel fuel."
Algae for Fuel
Growing algae for biodiesel is probably the most exciting frontier in the burgeoning field of biomass fuels. In an article entitled, "Algae Oil Could Dent U.S. Oil Imports, Report Says", Candace Lombardi, makes the point that: "The U.S. has enough land in the right climate to produce homegrown algae oil that would replace a significant amount of foreign oil imported for transportation use--without endangering its water supply." The Gulf Coast region, the Southeastern seaboard, and the Great Lakes areas are ideally suited to grow algae in outdoor freshwater ponds with minimal water usage. That's according to a study released (in April 14th, 2011) by the Department of Energy's Pacific Northwest National Laboratory (PNNL) in the journal Water Resources Research.
However, Lombardi goes on to note: "Biofuel made from refined algae oils, while showing promise, is still in the early stages of development. In addition to the usual scalability questions put to the developers of any new technology, algae developers have been under even closer scrutiny because a lot of water is required to grow it."
The article continues with this additional information: "The PNNL says its study is the first comprehensive land-use and water-use assessment of a potential algae oil industry in the U.S. PNNL researchers found that if you compare algae and corn hectare to hectare, algae grown in outdoor ponds annually produces 80 times more oil than corn. Theoretically, they said, the U.S. has enough available land to produce '48 percent of the current transportation oil imports' with algae. However, that level of production across the U.S. would require too much water--an average of 350 gallons of water to grow and produce one gallon of algae oil." This clearly would have a disastrous impact on freshwater supplies, making it impractical to implement on such a widespread scale.
The article goes on to offer an alternative to the massive production of algal oil that would be needed to grow 48 percent of U.S. oil needs: "...PNNL researchers, led by hydrologist Mark Wigmosta, recommend producing algae only in regions of the country with both the right land and high humidity. They found that if algae are grown in a climate already high in humidity, much less water is needed. The group also identified the regions mentioned above as the best places to grow it. This would still give the U.S. the ability to produce 21 billion gallons of algal oil a year; roughly 17 percent of the amount of oil that was imported for transportation in 2008".
Conclusions on Biomass Fuels
So, while using plants like miscanthus, soy, and algae to derive biofuels offers a variety of benefits including lower fuel costs, diminished levels of CO2 emissions, and a lessened dependence on foreign oil, we will have to choose carefully among them to derive the greatest environmental and economic benefits, all the while balancing the issues of land use, water consumption, and the overall costs to the environment and our ever-increasing human population.