As the U.S. Senate works to shape a national energy bill that contains a greater emphasis on conservation and renewable fuels than the House-passed energy bill, one component supported by environmentalists and the agriculture community dates back over 100 years, to the invention of the diesel engine. The "new" fuel rapidly gaining support is a variation of the fuel used in 1897 by Rudolf Diesel in his first engine - biodiesel.

As the United States seeks to reduce its dependence on imported oil, biodiesel is gaining increased attention. In recent years, biodiesel production plants have been proposed and backed by government funds as well as private investors. Earlier this month, it was announced that a biodiesel plant would be built in Pittsburgh, utilizing a new, more-efficient production method developed by Carnegie Mellon University's Center for Advanced Fuel Technology.

Biodiesel fuel has traditionally been produced from soybean oil, but other biomass material can be used including corn, rapeseed (canola oil), sugar cane and peanut oil (used in the first diesel engine).

Europeans have embraced modern diesel engines to the point that more than 50 percent of all new cars bought in Europe are diesel powered. The primary attraction is the 30 percent or better fuel efficiency advantage over convention gasoline engines.

The conversion to clean, low-sulfur diesel fuel, which occurred in Europe several years ago, will be duplicated in the United States over the next two years. This development will allow modern diesel engines to meet environmental standards and begin to erase the negative image Americans have of soot-belching diesel cars of the 1970s and 80s. Today's diesel engines are dramatically superior to those of 20 years ago and rival the cleanest gasoline engines in terms of exhaust pollution, while offering dramatic mileage benefits.

While the American farmland might not be a Saudi Arabia of biodiesel fuel, the potential for biodiesel growth to benefit U.S. farmers while cutting dependence on foreign oil cannot be ignored.

Biodiesel can be produced in just about every region of the United States, and production plants are generally much smaller and more environmentally friendly than petroleum production and refinement operations that are required to make conventional gasoline.

All European car manufacturers and most U.S. automakers offer diesel engines for their cars and light trucks - but not in the United States. The low-sulfur fuel being mandated by the federal government will help make diesel engines viable for American highways, and the 30 percent to 50 percent improvement in fuel economy will surely attract the attention of American drivers.

With gasoline prices above $2 per gallon - and no significant price reductions expected - the time has come for the increased efficiency and environmental benefits of diesel engines. This is especially true given the benefits of diesel engines running on renewable biodiesel fuel, which can be blended with petroleum-based diesel fuel at any ratio.

Along with the recent advances in hybrid vehicles, powered by both a gasoline engine and an electric motor, diesel engines offer the best opportunity to relatively quickly reduce America's consumption of imported oil. And running diesel engines on renewable biodiesel fuel further helps the U.S. reduce its dependence on foreign oil.

Diesel engines and biodiesel fuel can play a significant role in the United States' intermediate term energy picture. The final version of the energy bill signed by President Bush should reflect that reality.

- J.L.W.III