UK: Debate rages on structure of CO2 limits

By just-auto.com editorial team | 13 November 2007

The European Commission is still planning to present proposals for legislation on mandatory limits to CO2 emissions from light vehicles in December but there is no clear agreement yet on how the limits will be structured.

The voluntary agreement that the European vehicle manufacturer trade association, ACEA, and its Japanese and Korean equivalents signed up to in 1998 required the industry as a whole to achieve an average CO2 emission level for the vehicles sold during a given year. It is clear that some manufacturer groups are closer to achieving that target than others. Some manufacturers argue that this reflects the different make-up of manufacturers' product offerings and this should be reflected in the make-up of any legislation.

Speaking at a Low Carbon Vehicle Partnership (LowCVP) conference on promoting low carbon vehicles in London last week, Malcolm Fergusson of the Institute for European Environmental Policy (IEEP), who has been advising the European Commission, explained that there is ''some argument for allowing big vehicles to emit more if they have a utility function''.

This is supported by the fact that a framework for the legislation has been set that requires that it should be "equitable to the diversity of European vehicle manufacturers" and be competitively neutral.

But there is a lot of debate about the way that 'utility' should be defined.

According to Kai Lücke, public affairs director of ACEA, the best way of determining the 'utility' function of a vehicle is to determining its weight. "We support a weight-based system. We need to safeguard the diversity of industry."

But weight may not be the best way to define utility. There is a clear mathematical relationship between mass and CO2 that can be plotted via a regression analysis. But the fact that there is this relationship means that there is a danger that manufacturers add weight to get a higher CO2 allowance. This can be dealt with to some extent by giving heavier vehicles tougher targets relative to lighter vehicles, said Fergusson, but overall he concluded: "I don't think that weight is a good parameter as it could allow us to continue to add weight to vehicles as has been happening over time."

An alternative is to relate the utility function of a vehicle to its footprint (the area between the wheels). This is an idea supported by Friends of the Earth. Its transport campaigner, Tony Bosworth, noted that the US National Highway Traffic Safety Administration (NHTSA) has done a lot of research and analysis in this area and is moving away from a weight definition towards the footprint definition.

One of the arguments put forward by ACEA against using the footprint definition is that, because of platform sharing, different cars, for example, an SUV and a small car, could share the same footprint but have completely different CO2 values. Lücke argued that this measure discriminates against small cars. Fergusson noted that in the US NHTSA researchers have concluded that platform sharing could lead to benefits.

ACEA is also attracted to weight definition because it is already used in Japan and China. "Since it has been introduced in Japan weight has remained stable," said Lücke.

Clearly there is some disagreement within ACEA. Greg Archer, director of the LowCVP, questioned Lücke on the fact the French manufacturers, PSA and Renault, had said recently they would not be in favour of different CO2 limits based on weight.

"ACEA as a whole thinks weight is the best base for a utility definition," said Lücke , refusing to comment further. As volume manufacturers with a large number of small cars in their annual sales fleet they are closer to meeting the voluntary CO2 targets than some of the German manufacturers, for example, which are focused on executive and luxury vehicles. The French manufacturers have consistently argued for a blanket target for all manufacturers. According to yesterday's discussion this now seems highly unlikely.

Susan Brown