Excerpt
Improving Fuel Economy on Ethanol

One criticism of ethanol is that it replaces only a small portion of our gasoline use. But this is a poor reason to abandon ethanol. It would make no more sense than abandoning wind power because it can’t supply all our electricity. It is, however, a reason to work on conservation and energy efficiency just as intently as production. We use more energy than necessary, primarily because petroleum has historically been inexpensive. As cheap oil becomes scarce, we must find ways to curtail our use of transportation fuels.

Some ethanol critics cite its poor fuel economy compared to gasoline. Actually, ethanol can be an ally in energy conservation and better fuel economy. Preliminary studies show E10 already achieves better fuel economy than ethanol-free gasoline in some vehicles. E85 exhibits reduced fuel economy in today’s flex fuel vehicles, but critics often fail to acknowledge this situation can improve. Manufacturers could optimize vehicles for better fuel economy on E10 and E85. This would reduce our cost per mile driven. It would also improve ethanol’s energy balance, in turn benefiting our environment, energy security, and trade balance.

Ethanol’s energy density is low compared to gasoline, but energy density is not the only property affecting fuel economy. We must also consider how efficiently a vehicle uses energy. No technology is capable of converting 100% of available energy into useful work. Energy is lost to friction and heat. But vehicles optimized for ethanol are able to direct a greater percentage of available energy toward turning the wheels, offsetting lower energy content. This is possible thanks to ethanol’s high octane rating and other beneficial combustion properties. Ethanol optimization technologies already exist. Full implementation of these technologies could yield huge benefits through better fuel economy.

In these times of high fuel prices, we often hear of potential solutions such as hybrid vehicles, biofuels, hydrogen, and fuel cells. We need to resist the temptation to see these as competing alternatives. It is tantalizing to think some single “silver bullet” technology will solve all our energy problems. Realistically speaking, if we reject every energy alternative that can’t single-handedly replace oil, we will have nothing left. We need many different alternative fuels and most importantly, we need to combine fuels and technologies for maximum efficiency. Biofuels such as ethanol can be a valuable component of a highly efficient transportation system.