Could an 'emissions trading scheme' be the way to reduce CO2 emissions from Europe's truck fleet? That was among the topics discussed at the International Transport Forum. Cutting CO2 emissions from road transport took centre stage during a two-day meeting of experts from Europe and the US at the International Transport Forum (ITF) in Paris. Several possible methods of reducing emissions are already in place, including the London Low Emissions Zone. But the scheme expected to become the European  standard is an extension of the European Union Emissions Trading Scheme (EU ETS) to trucks, vans and other vehicles.

The EU ETS, which sets quotas for CO2 emissions from heavy industry, is to be extended to include the airline industry, with each EU country setting emissions quotas which are then shared between polluters. Companies that pollute more than their allocation must 'buy' quotas from 'cleaner' firms. The European Commission hopes this system will make it more economical for companies to clean up their act. Whether it could be expanded to include road transport is still under discussion at the EC. This possibility was the subject of a presentation at the ITF by Charles Raux of the Transport Economics Laboratory at the University of Lyon in France.

Raux suggested that if governments decide to tackle CO2 emissions from road users, rather than focusing on vehicle manufacturers or fuel producers, then a system of tradable emission permits would be by far the most  economical way to go. Other systems, based on the weight of vehicles, the distance travelled, or empty running would be "expensive to regulate and inefficient", he said. But Raux stressed that including the freight transport sector in the ETS would not be simple. Hauliers are directly responsible for emissions, as they own the vehicles and control their movements, but the companies they work for are also indirectly concerned, and any quota system would have to look at how this burden could be shared.

He suggested that sharing the cost of emissions could be included in the contractual agreements between hauliers and their clients, but this would probably remain voluntary and part of the wider negotiations between freight operators and their customers. "Hauliers could 'bank' the rights they negotiate on different orders from shippers," Raux told the conference. "If they make efforts to minimise their own fuel consumption, by grouping loads and reducing vehicle-kilometres, for example, they would pocket the difference." As for monitoring companies' use of the quotas allocated to them, he said this would have to take place each time trucks filled up with fuel, using smart cards which are already widely used by hauliers and which would have to be made obligatory. Companies buying fuel in bulk would simply pay their emissions rights at the same time as the fuel supplier's invoice.

The question of taxes was raised by another speaker, Stef Proost of the Centre for Economic Studies at the Catholic University of Leuven in Belgium. He suggested that the best way to reduce road use, and therefore emissions, was to cut taxes on fuel - or CO2 - but add a new tax per kilometre travelled that would vary according to country and vehicle type. This, he claimed, would lead to fewer trucks and cars on the road, with a resulting decrease in emissions. And while the EC is still considering whether the ETS should be extended to cover road transport, there are question marks over whether it would in any case be the best way to reduce road use. "For some goods their value is so high that variations in transport costs will have hardly any influence on distribution practices," Raux pointed out. And he predicted that hauliers would challenge Brussels over the economic impact of such a scheme, arguing that firms outside the EU would not be subject to the same system and could thus undercut European operators without being obliged to reduce their emissions.