National Geographic : 1981 Feb 28
Fields sproutfuel tanks in Brazil (right), where soaring petroleum costs spur the conversion of sugarcaneinto ethyl alcohol for making gasohol.In the U. S., gasohol made largelyfrom corn spreadsrapidly as a gasolineextender. With $1,100 in partsand labor(below), the president of California'sFutureFuels of America converts a Ford to run on straightmethyl, or wood, alcohol. Canadian province of Alberta. Two large facilities extract the oil. They, together with South Africa's coal-converting Sasols, are the vanguard in the measured march toward synfuels. When experts talk of synfuels, they often include two sources of oil that are extracted much like tar sands. One is heavy oil, petroleum so thick it must be liquefied underground, usually by injecting steam. The U. S. resource is huge-about 75 billion barrels-with the major portion in California. Today California fields yield 500,000 bar rels a day of this costly oil, and rising prices could see the level climb to 800,000 by 1985. Production could soar with the introduction of experimental submergible steam gener ators able to tap deep-lying deposits. The second source is conventional oil left behind in abandoned wells. Normally, pri mary and secondary extraction recovers only 30 percent of the oil. The residue holds promise, with new and expensive technol ogy known as enhanced oil recovery. This includes sending down detergents or liquid carbon dioxide to dislodge and mix with the oil; in a year or two the oil-rich mix can be pumped to the surface for separation. An other approach under study is oil "min ing"-digging shafts along the bottom of formations to drain the residual oil.