Energy . . . continued

Homegrown biodiesel . . . continued

Biodiesel is a diesel fuel derived from plant or animal sources, such as sunflower oil, canola oil, soybean oil, safflower oil and tallow (beef fat).  At least on a blended basis, it can substitute for petroleum-derived diesel in ordinary truck, car, tractor, train and other diesel engines.  Biodiesel can be blended with conventional diesel, for example in the so-called “B2” (2% biodiesel and 98% conventional diesel) and “B20” formulations (20% biodiesel), or, in some engines, used in pure form (“B100” biodiesel – 100% biodiesel).  (See North Dakota State University, “Biodiesel Fuel”, Feb. 2003)

“To make [biodiesel] fuel, [Hilltown Farmers Biodiesel Cooperative co-founder Mason explained] the [sunflower] oil is heated to 120 degrees Fahrenheit and methanol and potassium hydroxide are added. . . . The mixture sits for several hours in a reactor tank while refining, or ‘transesterification’ occurs. This separates the amber-colored biodiesel from a murky glycerin, a darker, heavier liquid that settles to the bottom.  The glycerin is drained off, and much of the methanol is recovered through a distillation process. The glycerin can eventually be used in soap-making. The biodiesel [then] goes through a light water wash and an ion-exchange procedure”, the Gazette reports.  Mason told the Gazette that, at current diesel prices, producing his own biodiesel is not “much of a bargain . . .  It's the independence . . . . It's cleaner, and using biodiesel fuel reduces (carbon dioxide) emissions by 78 percent, compared to diesel.”  The Hilltown Farmers Biodiesel Cooperative farmers are being trained in the biodiesel making process by Piedmont Biofuels of North Carolina notes the Gazette.

In addition to being a renewable fuel, and one that can be produced from domestic and local sources, biodiesel burns cleaner than ordinary diesel fuel.  (See “Sunflower Oil  Use in Biodiesel”) The National Biodiesel Board, a trade advocacy group, citing EPA studies, notes that pure biodiesel essentially eliminates sulfur emissions, and substantially reduces particulate, polycyclic aromatic hydrocarbon (PAH), and carbon monoxide emissions, as well as emissions of unburned hydrocarbons, compared to petroleum-derived diesel.  Nitrogen oxide (NOx) emissions, may, however, increase slightly with biodiesel.  (See National Biodiesel Board, “Biodiesel Emissions”) The European Biodiesel Board asserts that biodiesel also reduces emissions of CO2, the principal gas connected to global warming.

The National Sunflower Association notes that “[t]here is a great deal of interest from local areas for construction of small processing facilities for sunflower biodiesel production.” The Association does caution that because of its price premium compared to soybean and canola oils, sunflower oil may be cost-prohibitive as a major U.S. source for biodiesel production.  (See “Sunflower Oil  Use in Biodiesel”) However, the Association notes that “[s]unflower is a high oil content seed and average yields can produce 600 pounds of oil per acre, considerably more than soybeans”, which may be part of the explanation for the continued interest in sunflower-based biodiesel.  North Dakota State University estimated that an acre of sunflowers can produce about 84 gallons of biodiesel, compared to 49 gallons of biodiesel from an acre of soybeans.  (North Dakota State University, “Biodiesel Fuel”, Feb. 2003) European biodiesel production is heavily reliant on rapeseed oil. (See, e.g., NPR, "Biodiesel Demand Grows Across Continents," 9/2/07)

Environmentalists, food & nutrition advocates, "and some state environmental regulators, have questioned the wisdom of diverting food crops, like soybeans and sunflowers, to fuel production.  High demand for food crops for energy production can result in increased food prices, harming low-income Americans in particular. Moreover, food production may then be displaced to parts of the third world where forests may be cut to clear land for the expanded food production. That could mean that such biofuel production in the U.S. could indirectly worsen the global warming problem by spurring more third world deforestation. 

Beyond that, the energy calculus needs to show that biodiesel production actually results in net increases in energy, once the fossil fuel and other energy used to produce and ship the oil crops and process the oil is factored in.  A recent USDA study did show such a positive net energy return for biodiesel, at least when it’s based on soybean oil. The study concluded that U.S. biodiesel based on soybean oil creates biodiesel with an energy content more than four times that of the conventional energy used to produce the biodiesel. (USDA, “Energy Life-Cycle Assessment of Soybean Biodiesel,” September 2009) However, a 2005 study by David Pimentel of Cornell and Tad Patzek of the University of California at Berkeley concluded the opposite, that both soybean-based biodiesel and sunflower-based biodiesel consumed more energy in production than was contained in the final biodiesel produced. (“Ethanol Production Using Corn, Switchgrass, and Wood; Biodiesel Production Using Soybean and Sunflower,” Natural Resources Research, March 2005)

-- Rudy Perkins with Madeleine Charney

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