Bentley, which is owned by Germany's Volkswagen, says biofuels are the way to cut its CO2 emissions. For the company, in the short to medium term, this means using ethanol as the main renewable fuel. But many experts say ethanol doesn't cut GHG emissions and that Bentley's push for ethanol shows the company needs a quick and cheap way to appear like they are improving fuel economy, the Detroit News reports.
Jerry Taylor, senior fellow at the Cato Institute in Washington, D.C., told the paper that if the energy needed to produce ethanol until it reaches the fuel tank is added up, the so-called “well-to wheel” measurement, the alternative source of fuel doesn't cut GHG emissions.
At the Geneva Car Show in early 2008, Bentley CEO Franz-Josef Paefgen said “Bentley's contribution to overall CO2 emissions is negligible... But we still need to act. Taken together, the measures we are announcing will make the entire Bentley fleet capable of delivering less than 120g/km (grams of CO2 per kilometer) by 2012 (the equivalent of about 46 mpg)."
Paefgen says the well-to-wheel measurement is the “only accurate way to measure the total energy expended from every stop for the life cycle.” General Motors' Swedish subsidiary Saab, and Ford of Europe say that growing crops to produce ethanol sucks in CO2 and that by the time it reaches the car and is burned off to drive the wheels, the alternative fuel would provide up to 70 percent in CO2 reduction.
However, others disagree and say the production process' use of water, energy, fertilizer and transport actually used more energy than was being saved
Last year, the company's Subcompact Car Bentley Continental GTC was ranked as one of the lowest fuel economy by vehicle class by the EPA and the DOE.
