Biodiesel: Virtually any diesel car can run on biodiesel which is produced from natural, renewable resources such as soybeans or recycled vegetable oil. It is safe, biodegradable and reduces air pollution, compared to petroleum diesel. Researchers are working to make bio-diesel out of coal, bio-plastic, pond-scum algae and even pig manure. And you thought regular diesel exhaust smelled bad!
Natural gas: The same stuff you heat your home with is one of the cleanest and cheapest alternative fuels available. Less expensive than gasoline, natural gas is most often found in government owned cars or commercial fleets. This option is just beginning to break into the retail market with vehicles such as the Honda Civic GX.
Electricity: The obvious pluses are zero tailpipe emissions, low cost per mile and the promise of publicly available charging outlets. The downside? Battery packs used to power electrical vehicles are expensive and leave electric cars with a short operating range before recharging is needed. And have you ever thought about where the electricity comes from to charge these? If it is coal fired power plants we may not be gaining much energy savings.
Hydrogen: This long term hope would be a clean, low emission fuel extracted from methane, or perhaps someday even water may power fuel cells, like those developed for use on the space shuttles. The only by-products are heat and water vapor making this an environmental home run candidate. It is not yet commercially available, but research and development, including test fleets are underway.
One aspect of fuel cell development that I find exciting is the potential for each home to have a fuel cell, eliminating the huge waste of power lost in transmission from power plants hundreds of miles away. That alone could cut our residential energy consumption in half. You heard me right, half.
There is no obvious winner of the alternative fuel stakes on the horizon, but stay tuned. With $3 gas, every time you and I fill up our cars, we are doing our part to make many things that could not be done before economically feasible.