Electricity not Ethanol

SUBHEAD: Electricity from corn will propel cars further than ethanol ever will.

By Jeremy van Loon >on 8 May 2009 in Bloomberg News -

Image above: Corn Ethanol and Pig-Cars cartoon by Simanca Osmani, Cagle Cartoons, Brazil.

Burning sugar cane or corn to make electricity for powering cars may be smarter than refining the crops into biofuels. That’s because the vehicles may travel farther on “bioelectricity.” The improvement in mileage is about 80 percent, said Elliot Campbell, a researcher at the University of California at Merced.

Turning food into electric-car fuel also releases less carbon dioxide gas compared with burning biofuels made from the same plants, he said. Toyota Motor Co. and General Motors Corp. are among the carmakers looking for ways to lower consumption of gasoline and diesel. The industry is struggling through the worst slump in sales in decades amid tougher regulations on CO2 emissions. “It’s not our plan to put all our eggs in one basket,” Toyota spokesman Paul Nolasco said. “There’s no single approach that can be applied to all situations.

The solution depends on where you are and how available different kinds of fuel are.” Alternatives include using electricity or fuel made with plants, such as corn from the U.S. Midwest or sugar cane from Brazil in the form of ethanol.

Also there are more complex synthetic fuels from transforming wood chips and farm waste. Plant-based fuels are gaining popularity among investors partly because they are less polluting than gasoline, though they contain less energy per unit volume. Refining them consumes additional energy, often using fossil fuels.

Brazil Example
Brazil is the world’s second-largest producer of ethanol and no longer has any cars and pickups running on pure gasoline. The South American country requires that automotive fuel be 25 percent ethanol. Sugarcane ethanol accounts for almost 17 percent of the total energy consumption by the automotive sector, according to Brazil’s energy ministry.

Last year, rising demand for biofuel driven by government attempts to fight global warming was blamed for surging prices for corn, rice and soybeans. Higher prices prompted South Korea and Japan to consider investing in agriculture abroad to ensure a stable supply of food. Governments are offering aid to biofuel manufacturers to speed development.

Biofuel subsidies in various forms in the EU, Canada and the U.S. totaled about $11 billion in 2006 and are set to climb to $25 billion by 2015, according to a report by the Organization of Economic Cooperation and Development. Using fuel made from corn in the U.S. reduces emissions by 10 percent to 30 percent compared with burning gasoline to drive the same distance, the OECD study from last July said. Campbell and colleagues investigated land-use efficiency, or how much transportation can be achieved per acre of cropland that’s being used to produce plants for energy. The study was published today on Science magazine’s Web site.

 ‘Lot More Transportation’
 “What we found is that if you burn this biomass to make electricity to power electric vehicles, you can get a lot more transportation than if you convert it into ethanol,” Campbell said in a podcast on Science’s Web site. Bioelectricity can be more efficient than biofuels largely because electric motors are economical, he added. Automakers are testing the dynamics.

Nissan Motor Co. plans to sell an all-electric car globally by 2012 while GM aims to roll out a car named the Volt by 2010 that will be mostly electric-powered. Second-generation biofuels, or those using materials like switch grasses and wood chips to create synthetic fuels, require more “technology advances” in order to make them economically competitive, Campbell said.  

Daimler, Volkswagen
 Several companies including Germany’s Choren Industries GmbH, which has partnerships with Daimler AG and Volkswagen AG, are racing to develop synthetic biofuels to help meet tougher rules on emissions. The European Union aims to slash CO2 emissions using renewable energy from the wind, sun and fuel plant derivatives. The 27-member bloc plans to cut carbon output for vehicle fleets to 130 grams a kilometer gradually by 2015. The UN Intergovernmental Panel on Climate Change has said that global emissions cuts of 50 percent to 85 percent are needed by 2050 to stand a chance of containing the average increase in temperature to 2 degrees Celsius (3.6 degrees Fahrenheit).

Bioelectricity Promises More ‘Miles Per Acre’ Than Ethanol

SOURCE: Ken Taylor (taylork021@Hawaii.rr.com)
By Carnegie Institute on 7 May 2009 ;


Biofuels such as ethanol offer an alternative to petroleum for powering our cars, but growing energy crops to produce them can compete with food crops for farmland, and clearing forests to expand farmland will aggravate the climate change problem. How can we maximize our "miles per acre" from biomass? Researchers writing in the online edition of the May 7 Science magazine say the best bet is to convert the biomass to electricity, rather than ethanol.

They calculate that, compared to ethanol used for internal combustion engines, bioelectricity used for battery-powered vehicles would deliver an average of 80% more miles of transportation per acre of crops, while also providing double the greenhouse gas offsets to mitigate climate change. "It's a relatively obvious question once you ask it, but nobody had really asked it before," says study co-author Chris Field, director of the Department of Global Ecology at the Carnegie Institution.

"The kinds of motivations that have driven people to think about developing ethanol as a vehicle fuel have been somewhat different from those that have been motivating people to think about battery electric vehicles, but the overlap is in the area of maximizing efficiency and minimizing adverse impacts on climate."

 Field, who is also a professor of biology at Stanford University and a senior fellow at Stanford's Woods Institute for the Environment, is part of a research team that includes lead author Elliott Campbell of the University of California, Merced, and David Lobell of Stanford's Program on Food Security and the Environment. The researchers performed a life-cycle analysis of both bioelectricity and ethanol technologies, taking into account not only the energy produced by each technology, but also the energy consumed in producing the vehicles and fuels.

For the analysis, they used publicly available data on vehicle efficiencies from the US Environmental Protection Agency and other organizations. Bioelectricity was the clear winner in the transportation-miles-per-acre comparison, regardless of whether the energy was produced from corn or from switchgrass, a cellulose-based energy crop.

For example, a small SUV powered by bioelectricity could travel nearly 14,000 highway miles on the net energy produced from an acre of switchgrass, while a comparable internal combustion vehicle could only travel about 9,000 miles on the highway. (Average mileage for both city and highway driving would be 15,000 miles for a biolelectric SUV and 8,000 miles for an internal combustion vehicle.) "The internal combustion engine just isn't very efficient, especially when compared to electric vehicles," says Campbell. "Even the best ethanol-producing technologies with hybrid vehicles aren't enough to overcome this."

 The researchers found that bioelectricity and ethanol also differed in their potential impact on climate change. "Some approaches to bioenergy can make climate change worse, but other limited approaches can help fight climate change," says Campbell. "For these beneficial approaches, we could do more to fight climate change by making electricity than making ethanol." The energy from an acre of switchgrass used to power an electric vehicle would prevent or offset the release of up to 10 tons of CO2 per acre, relative to a similar-sized gasoline-powered car. Across vehicle types and different crops, this offset averages more than 100% larger for the bioelectricity than for the ethanol pathway.

Bioelectricity also offers more possibilities for reducing greenhouse gas emissions through measures such as carbon capture and sequestration, which could be implemented at biomass power stations but not individual internal combustion vehicles. While the results of the study clearly favor bioelectricity over ethanol, the researchers caution that the issues facing society in choosing an energy strategy are complex.

 "We found that converting biomass to electricity rather than ethanol makes the most sense for two policy-relevant issues: transportation and climate," says Lobell. "But we also need to compare these options for other issues like water consumption, air pollution, and economic costs."

"There is a big strategic decision our country and others are making: whether to encourage development of vehicles that run on ethanol or electricity," says Campbell. "Studies like ours could be used to ensure that the alternative energy pathways we chose will provide the most transportation energy and the least climate change impacts."


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