The grain needed to fill the fuel tank of a typical SUV could feed a person for a year, says a leading international environmentalist.

Lester Brown, executive-director of the Washington, D.C.-based Earth Policy Institute, says a global rush to alternative fuels made from food crops is likely to increase hunger in the poorest countries.

"What has happened in the last few years is that the runaway price of oil has made the conversion of agricultural commodities into fuel for cars extraordinarily profitable," he told a conference at the University of Ottawa.

"Almost everything we eat can be converted into fuel for cars: wheat, corn, rice, soy beans, sugar cane, you name it. There have been times in recent months when the price of ethanol in the United States was double the cost of production. That's a good margin."

Last year the U.S. ethanol industry consumed 55 million tonnes of corn, more than the entire Canadian harvest, Brown said.

He said new biofuel plants are being announced somewhere in the world at a rate of more than one every day. There are 105 U.S. ethanol plants, with about 40 under construction and another 50 to 75 being planned.

Canada has also seen rapid expansion of the ethanol industry and the federal government has encouraged this with an exemption from excise tax and a pledge to require all automobile fuel to contain five per cent ethanol.

Provinces are also eager ethanol supporters. Earlier this month, Alberta allocated $209 million over four years to encourage the renewable fuels industry by 2010.

Although ethanol is usually promoted on environmental grounds, its actual environmental benefits are subject to debate, while the impact on food supplies has received scarcely any notice.

Brown said the priorities for agriculture should be food and feed, not fuel.

"There is no international body to mediate the competition between 800 million people with cars and two billion of the poorest people, who spend more than half their income on food.

"It is one of the most important, politically disruptive issues on the horizon today. The risk is that rising grain prices in low-income countries that import a lot of their grain could lead to food riots and political instability on a scale we've not seen before."

He suggested there are much greater benefits in developing wind power.

Governments could use tax policy to encourage a shift to gasoline hybrid vehicles which use electricity, and provide the electricity for these vehicles using wind power.

Brown cited U.S. government studies showing that wind power could satisfy all the country's energy needs, and suggested Canada's wind resources would be even more abundant.

Robert Hornung, president of the Canadian Wind Energy Association, says there has been a freeze on federal support for wind energy projects since April, as the new government considers its options.

He said incentives created by the former government led to a boom in the industry, pushing Canada's wind power capacity to a record 1,218 megawatts last year, enough to power 370,000 homes.

The uncertainty about the Conservative government's intentions has left many investors wondering whether to proceed with plans for new wind farms, he said.

Kory Teneycke, executive director of the Canadian Renewable Fuels Association, said he has seen no evidence that expansion of the biofuels sector could aggravate world hunger.

He said there is no shortage of food in the world, that the reasons for hunger are complex.

The renewable fuels sector is also eager for government support, and is looking for details on how the government plans to achieve its five per cent ethanol mandate.