Higher ethanol blends would be good for U.S.: Chu

NEW YORK (Reuters) - Mixing slightly higher levels of ethanol into gasoline would benefit the U.S. energy supply provided the higher blends do not hurt car engines, U.S. Secretary of Energy Steven Chu said.

"We are looking at whether when you go up to 12 and 13 percent (of ethanol in gasoline) whether the current fleet of automobiles would be fine in terms of the gaskets and seals and things of that nature," said Chu speaking at the Reuters Global Energy Summit in Washington. "If it turns out the existing automobile fleet ... could accept that, it would be good if we can go up to 12 or 13 percent."

The Environmental Protection Agency said last month it was extending the public comment period until July 20 on a proposal to increase the amount of ethanol that could be blended into gasoline to as much as 15 percent per gallon. The EPA said it has up to December 1 to act on the request.

The U.S. government approves blending up to 10 percent ethanol into gasoline burned in cars and trucks that have not been specially made or converted to burn high levels of ethanol. Producers and groups such as Growth Energy are pushing the government to allow higher ethanol blend levels.

Congress required 9 billion gallons of ethanol and other biofuels to be blended into gasoline last year. The amount will rise annually toward 36 billion gallons a year in 2022.

Chu said the country should move as quickly as possible beyond corn, the main feedstock for U.S. ethanol. But he would not say whether producers would succeed in meeting the country's first mandate for blending cellulosic ethanol, the advanced biofuel expected to be made from non-food crops such as switchgrass and fast-growing trees.

The 2007 Renewable Fuels Standard calls for the blending of 100 million gallons of cellulosic ethanol into U.S. gasoline next year.

"I don't actually have my finger on exactly where the cellulosic biofuels are in terms of when they think they can make the mandate. So it really depends," said Chu.

"We do have some pilot plants and projects in operation, but we are hopeful than we can do better than the type of technology we're investigating with the pilot plants today," he said.

Corn ethanol has been blamed for a variety of problems including helping to raise food prices and pollution from the fertilizer used to grow the grain.

"I would rather see as quickly as possible if we can develop the technology that would allow the American farmers to transition to cellulosic ethanol," Chu said.

(Reporting by Timothy; Editing by Lisa Shumaker)