Propane is back

Propane-powered tractors, first innovated by Minneapolis-Moline in 1941, faded from use in agriculture decades ago. But the clean-burning fuel is enjoying a resurrection. John Deere has pitched in to help the Southwest Research Institute build a propane engine for agricultural use.

The resulting Deere Model 5410 tractor is the first of its kind configured with a propane system featuring electronic controls. The tractor features a lean-burn combustion system and electronic control to cut pollution emissions. The components used on the tractor have been designed to fit existing machinery with minimal changes.

"Lower emissions will become extremely important when stricter EPA regulations go into effect for off-road vehicles in 2008," says Propane Education & Research Council programs manager Mark Leitman. Tier 3 standards will be mandated in 2008 that will restrict off-road equipment emissions of nitrogen oxides and non-methane hydrocarbons. Propane engines have been found to reduce nitrogen oxide emissions by more than 50% compared to a diesel engine.