University of California Transportation Center

The search for petroleum alternatives is not new. Ever since the turn of the century, when petroleum became the dominant transportation fuel, authoritative sources have warned occasionally of impending oil shortages (1, 2). When oil prices rose or oil depletion seemed imminent, interest and investments in oil shale, ethanol, coal liquids and gases, and tar sands surged; when oil prices subsided or estimated costs of alternatives escalated, interest and investments in the alternatives waned. Not until recently have several countries actually replaced substantial quantities of petroleum transportation fuels: Canada and South Africa built large production plants to produce gasoline and diesel fuel from tar sands and coal; Brazil replaced most gasoline with ethanol fuel; and New Zealand replaced almost half its gasoline with natural gas-based fuels.