Drivers in every US state except Hawaii and Alaska could be pumping petrol containing ethanol by 2012 if a plan approved by the senate becomes law, according to an Associated Press (AP) report published in the New York Times.

AP said the proposal, incorporated in a broad energy bill, would change how refiners blend petrol and how they meet clean-air requirements. It would require doubling the use of ethanol, to at least five billion gallons a year, in what would be a boon to corn farmers.

AP noted that methanol is made mainly in the US midwest from corn, although it can be produced with other grains and biomass. Under the bill, refiners in every state except Alaska and Hawaii would have to use it.

The measure, approved 67 to 29, would also ban the use of another petrol additive, methyl tertiary butyl ether, or MTBE, a derivative of natural gas that can contaminate supplies of drinking water, the Associated Press report said, noting that MTBE has been added to petrol in many states since the 1970s to increase the octane rating and make the fuel burn more cleanly.

AP said refiners would have more freedom to blend fuel because the measure would also end a requirement that petrol contain at least 2% oxygen in areas with air pollution problems. Although the rule has been credited with achieving significant reductions in tailpipe pollution, refiners say they can produce cleaner petrol without it, the report added.

According to Associated Press, opponents said expanding the use of ethanol could lead to petrol shortages and price surges in regions without ethanol plants. The ethanol industry says it does not anticipate problems meeting increased demand under the plan, which would be phased in over eight years, the report said.

Backers of ethanol said the bill would help energy independence by displacing up to 250,000 barrels of oil a day by 2012, AP said.

The news agency said that, as the senate began debating the fuel rules this week, the ethanol industry issued a report commissioned by the National Association of Corn Growers that estimated that doubling the use of ethanol would add $US1.3 billion a year to farmers’ incomes and create 214,000 jobs while lowering the cost of petrol.

Opponents argued that refineries in California and the Northeast, far from ethanol plants, might have trouble obtaining it. Exempting the Northeast and Far West would resolve the problem, some Democrats from those regions said, according to Associated Press.