General Motors is reportedly getting more serious about encouraging NASCAR to switch to ethanol.

According to press reports, GM plans to file a formal petition asking that it join other racing leagues and start using ethanol to power its racecars.

GM sponsors 22 NASCAR vehicles under its Chevrolet nameplate, about half the vehicles that start any given race. It’s been promoting more environmentally friendly fuel for months, and now it plans to proceed with an official presentation to NASCAR ownership.

“We do have the technical know-how,” said Brent Dewar, the vice president of GM North America sales, service and marketing. “It’s something we would have to work in conjunction with NASCAR on. NASCAR would have to encourage other manufacturers to do it as well.”