DME: another potential renewable fuel?

Biofuels. Solar. Wind. Tidal. Algae. Switchgrass. In the alternative energy debate, there are many sources of energy that are exotic, even “sexy.”

There’s one source, however, that has much potential but falls under the radar: dimethyl ether, or DME.

DME can be substituted for LPG (liquefied petroleum gas, which fuels many buses in Southern California). It emits almost no emissions, burning cleanly with hardly any particulates. Its sources are abundant: DME is created out of natural gas, petroleum, and coal extraction, and it’s also a byproduct of biomass. In fact, you’ve probably already come across it—many cosmetic products are sprayed out of cans using DME as a propellant.

Currently DME is used as a cooking fuel in China and some third world countries—it’s a cost-effective energy source that’s not subject to the wild fluctuations in oil and natural gas prices. And baby steps are being taken in using DME as a transportation fuel—Volvo in Sweden has been experimenting with DME-powered trucks, and currently Japan is the leader in DME research and technology. Sweden, however, has an interesting feedstock for DME—black liquor (no, not something in an LA $15 martini!), a byproduct, nasty byproduct, of pulp and paper processing. What was once a pollutant could now be an unlimited source of fuel for Sweden’s trucking fleets.

Of course a switch will not be easy. Governments may balk at pursuing a fuel that comes from a “dirty” or “fossil” source. It’s expensive to retrofit refineries, fueling stations, and vehicles to accommodate a new transport fuel. Like other non-petroleum fuel sources, DME would probably have its best application in a fleet approach—as a source for a network of municipal buses, taxis, or trucks that can run all day and then fuel up overnight.

My feeling is, we’re already mining coal and extracting oil and gas—why not use DME as another tool in our energy kit?