Volvo Trucks has started public field testing in Sweden of diesel trucks that can run on liquefied methane gas, or what is more commonly known in this country as liquefied natural gas or LNG.

Trucks running on liquid gas combined with methane diesel technology have up to four times longer driving range compared to most traditional LNG trucks.

"Increased use of gas is a bridge towards climate-neutral transports," said Lars Mårtensson, environmental director at Volvo Trucks. "Biogas production is already taking off in many countries. We're currently in a transition period, moving from decades of dependence on oil to a society built on renewable fuels. When trucks can operate on 80 percent pure biogas and 20 percent pure biodiesel, carbon emissions will be 80 percent lower than with conventional diesel technology."

Three Volvo FM trucks with 13-liter engines are currently being field tested. The technology is based on Volvo's proven Euro 5 diesel engine, which has been converted for gas operation.

The field test trucks are equipped with special tanks for the gas. When LNG and diesel are used in a ratio of 75-25, a truck performing long haul or intercity duties has an operating range 500 to 1000 km, depending on driving conditions. This is twice the operating range of methane diesel vehicles running on compressed gas and four times that of gas trucks with Otto engines.

"Until the infrastructure for liquid methane gas has been fully expanded, it is also a great advantage for trucks powered by methane diesel engines to be able to run on diesel alone,"said Mats Franzen, manager of engine strategy and planning at Volvo Trucks.

The field test vehicles are being operated by transport companies DHL, Götene Kyltransporter and Renova. The start of the field tests coincides with the inauguration of Sweden's first public filling station for LNG at Stigs Center in Göteborg, Sweden. The station is a collaborative project between Volvo Trucks, Fordonsgas Sverige and Göteborg Energi.

Filling stations have previously only existed for CNG (compressed natural gas).

"Volvo's focus on liquid gas opens up a whole new market for us," says Bo Ramberg, CEO, Fordonsgas Sverige AB. "Now it will also be very attractive for heavy vehicles to run on gas, and we expect that market to grow rapidly. To encourage this trend, we want to show that the infrastructure is being developed accordingly."

Three filling stations for LNG have been planned in Sweden to date. Besides the completed one in Göteborg, Aga will open a filling station in Stockholm, and Eon will open one in Malmö. Volvo Trucks is a partner in all the projects. There are plans to build additional stations if demand increases.