House and Senate negotiators on the US energy bill will be asked to give ethanol a larger share of the US fuel market sooner than is now proposed, backers of the renewable fuel said, according to Reuters. Both chambers support a so-called renewable fuels standard that would require use of five billion gallons a year (19 billion litres) of ethanol at the end of a decade - the Senate puts the target at 2012, the House sets it at 2015, Reuters said.