In the search for efficient alternatives to fossil fuels, producer of heavy trucks and transport solutions, Volvo Trucks, and other companies are at work, in Sweden, developing a new, highly efficient biofuel as a vehicle fuel.

Volvo Trucks is working with the European Union, the Swedish national authority for energy policy issues Swedish Energy Agency, Danish chemicals specialist Haldor Topsoe, oil and gas company Total, Swedish petroleum corporation Preem and biofuels producer Chemrec on this project, which started in September 2008, and will stretch over a total of four years.

There is a clear trend towards using increasingly large and heavy trucks for longer routes and, it is these energy-intensive transporters, reports the company, that are the focus in this strategic environmental drive by Volvo Trucks.

Dimethyl ether (DME) is a gas that is transformed into a liquid under low pressure, ensuring that its relatively straightforward to handle. As a fuel in a diesel engine, DME provides as high an efficiency rating as a traditional diesel engine, but with a lower noise level. The combustion process produces no soot, so a far simpler method of treating the exhaust gases can be used after emission. Also, the engine can produce a higher torque when starting off, which improves driveability.

EU estimates indicate that by 2030, Bio-DME has the potential to replace more than 50 % of the diesel oil currently used for heavy road transport. DME can be produced from natural gas and from a variety of biomass sources, in which case it is known as Bio-DME.

The Volvo Trucks project involves the development of DME fuel from black liquor, a by-product of the forestry industry. Alongside the Chemrec plant, in Piteå, in northern Sweden, construction has started on a facility for extracting DME from black liquor obtained from the nearby pulp plant. The cooking chemicals produced by the gasification of the black liquor are then sent back to the pulp plant, creating a closed circuit with unparalleled energy efficiency.

Volvo Technology DME project manager Per Salomonsson says that DME is the most efficient biofuel in existence, from its fuel production to its use in the engine. When Bio-DME is made from black liquor in a pulp plant, there is a 95 % lower carbon dioxide emission compared with emissions from fossil diesel.

The company reports that it is five times more efficient than biodiesel in terms of the transport kilometres obtained from each hectare of land used for the raw material cultivation.

Meanwhile, Volvo Trucks director for environmental affairs Lars Mårtensson says, "The Bio-DME project creates exciting new possibilities for testing DME in realistic conditions among our regular customers." From mid-2010, 14 Volvo FH trucks will be field tested in regular day-to-day operations by customers throughout Sweden.

Preem will be responsible for distributing Bio-DME and will build four Bio-DME fuel stations for the test trucks so that the trucks can be used under entirely normal regional and local operating conditions.

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