The viability of yet another alternative fuel option – as if fleet managers need more choices in an already crowded field of choices – moved a step closer to reality yesterday when the state of California approved the use of dimethyl ether (DME) as an on-road fuel.
According to Oberon Fuels, “this latest approval builds on earlier approvals and ongoing work by other regulatory bodies, including the US Environmental Protection Agency, the California Air Resources Board, and ASTM International, and will help accelerate commercial adoption of this low carbon fuel.
“The use of fuels like DME will reduce greenhouse gas (GHG) emissions, improve air quality and lead to a positive impact on California and the environment,” said Kristin Macey, director of the Division of Measurement Standards at the California Dept. of Food and Agriculture, which issued the latest approval of DME fuel.
Oberon, which is working with Volvo to test heavy-duty trucks running the fuel, describes DME as a “clean-burning, non-toxic fuel that can be derived from renewable sources. Its high cetane number and quiet combustion, as well as its inexpensive propane-like fueling system, make it an excellent, inexpensive diesel alternative.”
“The state of California’s approval builds upon the growing body of certifications that demonstrate DME is a low carbon fuel that meets both industry standards for performance and environmental standards for compliance,” said Rebecca Boudreaux, Ph.D., president of Oberon Fuels. “These approvals are a key step in increasing confidence among distributors, engine manufacturers and fleet owners that DME is ready for commercial markets, which will benefit Oberon as we build out a global supply of DME fuel.”
Last August, the EPA approved biogas-based DME for inclusion under the Renewable Fuel Standard and made it eligible for Renewable Identification Numbers (RINs) credits based on EPA findings that the fuel achieves a 68% reduction in greenhouse gases, said Oberon.
I had the chance to interview Boudreux back in 2014 about the fuel for a story on alternative fuel options. At the time, she was confident that DME would provide not only a viable alternative option, but would become a significant player going forward in the fuel mix.
She explained that the fuel can be chemically made from anything that produces methane—food waste, natural gas, landfills, and even animal waste. It also offers plenty of power to drive commercial vehicles of all sizes.
“When you look at DME from a power [standpoint], 1 gal. of DME produces 69,000 Btu,” Boudreaux said, adding that it takes about 1.88 gal. of DME to equal the power of 1 gal. of diesel. “It’s about comparable to LNG [in terms of power], which I think is around 70,000 Btu. It’s much higher than CNG.”
Volvo and Mack Trucks are both working towards producing DME-fueled tractors.
“This certification is a major step forward in developing the market for DME, especially for California-based heavy-duty fleets,” said Susan Alt, Volvo Group North America’s senior vice president of public affairs, which has been collaborating with Oberon on commercial vehicle demonstrations. “Volvo Trucks is continuing to invest in DME because it delivers diesel-like performance with propane-like handling and will provide a faster ROI for truck customers than other alternative fuels. Each certification increases their confidence that the fuel is good for trucks and the environment.”
When DME actually hits the roads as a publically-available fuel remains to be seen, but each step taken moves it that much closer to what its supporters believe will be a significant threat to the current vehicle fuel mix.