Someone posted a question in a Private Message on the comparison of gas to diesel, so I thought I would share our reply. Here are a few point on the fuel comparison: 1) As an example, a 25hp diesel engine consumes about 0.9 gallon per hour--a gas engine consumes about 1.8 gallons per hour. As a result, in the average mowing season of 1,000 hours, the diesel engine will burn 900 less gallons of fuel compared to gas engines. 2) Diesel with an estimated fuel price of $3.65/gal consuming 0.9 gal/hour will cost you $3.29/hour of mowing. For gas engines with an estimated fuel price of $3.36/gal consuming 1.8 gal/hour will cost you $6.05/hour of mowing. As a result: The annual fuel expense for gas is $6,050 compared to diesel expense of $3,290--so savings of $2,750/year of cutting (again based on 1,000 hours). Diesel has 42% less CO2 (carbon dioxide) and lower carbon monoxide and hydrocarbon emissions than gasoline. Diesel engines generate more torque for the horsepower. And lastly, diesel engines typically have a longer service life than gas engines.