Add U.S. construction-company fleet managers to the list of possible beneficiaries of the growing national gas boom, but the payoff is at least two years away. Dimethyl ether, a diesel replacement product that can be made from a variety of chemical feedstocks, could power a new line of heavy-duty trucks due in 2015 from a Volvo North America and Mack Truck partnership.
Natural gas will be the primary raw material used in dimethyl ether (DME) production, says Andre Boehman, a University of Michigan engineer who partnered with Volvo to develop the DME truck line. Converting gas to DME solves some logistical problems associated with LNG and CNG as the fuel can be handled just like propane and the infrastructure is already in place to transport and distribute it. Oberon Fuels, San Diego, has developed a modular, fleet-scale production platform, which gave Volvo-Mack confidence to base a new line on the fuel.
Alternative fuels usually require strong political support to get to market. However, there has been scant political support for DME because there has been no compatible vehicle technology, Boehman says. "For years, I couldn't find a single research dollar," he notes.
Elliot Hicks, chief operating officer of Oberon, says DME emerged as Volvo's foundation for a new vehicle line after years of market analysis "based on cetane level, zero particulate emissions and the potential to meet more stringent environmental guidelines."
DME can be burned in diesel engines but with different fuel injection and exhaust systems than its petroleum counterpart. Boehman says a major advantage of DME is that it burns clean and needs no particulate filter, greatly increasing the efficiency of the compression-ignited engines that use it as a fuel.
Göran Nyberg, president of Volvo Trucks North America sales and marketing, says, "We believe DME has great potential in the North American market, and, when produced from biomass, it can provide a 95% reduction in CO compared to diesel."