A shift to lightweighting demands heavyweight political support

Lighter vehicles offer the opportunity to reduce CO2 emissions from all vehicles. However, continuing to focus on a mass-based approach is an opportunity lost, writes Patrik Ragnarsson.

By Patrik Ragnarsson

17 Apr 2018

The EU can be proud of its efforts in spearheading the fight against climate change. Being at the forefront of the development of low carbon mobility will increase the competitiveness of the European automotive value chain. 

However, regulations can only drive competitiveness if they are implemented with cost effectiveness in mind. A cost-effective regulation must ensure that all the opportunities are available to make a difference. Lightweighting is one of the opportunities that up until now has not been used to the full potential. 

Although a shift towards low-carbon mobility is already underway, with growing numbers of hybrid and electric vehicles, there are other measures available capable of making a further contribution. 


One of the easiest of these is to make vehicles lighter. Lightweight solutions can be considered as a ‘low hanging fruit’, but the reality is that the European Commission is not considering it on equal foot as other technologies.  

It offers a simple, effective yet substantial contribution. Each kilogram less means lower emissions and higher energy efficiency for the same distance travelled. Whether they are powered by fossil fuels or use hybrid technology, lighter vehicles are more fuel efficient and therefore emit less CO2.

Despite this, the EU’s current method for setting targets for vehicle CO2 emissions is based on vehicle mass, an approach which fails to make allowances for the contribution of lightweighting. 

Because the CO2 targets are spread across all manufacturers, any company that manages to reduce the weight of its vehicles will actually see its target tightened. This means that there is not enough incentive for manufacturers to seek opportunities to further reduce weight. 

"The EU’s current method for setting targets for vehicle CO2 emissions is based on vehicle mass, an approach which fails to make allowances for the contribution of lightweighting"

Yet the ability to offer ideal lightweight solutions already exists. Aluminium components can weigh as little as half that of their steel counterparts. Already, many modern cars are for example replacing heavier steel doors with aluminium doors. 

The average European car today are using 150kg of aluminium, but there are great opportunities to increase this further. Using 200kg aluminium rather than steel in a petrol-powered car could save up to 16g of CO2 per kilometre. 

Even electric vehicles benefit indirectly; carrying less weight means they need fewer heavy batteries, extending their range and making them cheaper to run. But with the current system in the EU regulation, switching to lightweight solutions will not be fully rewarded.  

The revision of the regulation which determines targets for CO2 emissions from cars and vans is an opportunity to correct the negative effect of the mass parameter.   This is why European Aluminium urges the European Parliament and member states to seize the opportunities offered. By removing the mass-based approach, it can render the regulation future-proof, technology neutral and cost effective. 

"By removing the mass-based approach, the European Parliament and member states can render the regulation future-proof, technology neutral and cost effective"

Such an approach is not contentious; many studies - including those undertaken by DG CLIMA themselves - demonstrate that a mass-based approach is not the most cost-effective way for vehicle manufacturers to reach their CO2 reduction objectives. In fact, they show that, for a 2025 CO2 target, removing the mass-based approach would make it more cost effective for manufacturers to comply. 

How to ensure technological neutrality? There are two ways the regulation could be adapted. The first approach would be to shift from the existing mass-based system to one that is based on the size (footprint) of the vehicle. Since this is technology neutral, manufacturers benefit from investments in lightweighting, irrespective of the propulsion method of the vehicle. 

The second approach is to phase out the mass-based approach by suppressing the utility parameter, instead setting uniform reduction targets for all manufacturers. This means that all of them will be requested to reduce their emissions with the same percentage. 

Whichever approach is favoured; there will be direct and indirect benefits for the environment and for consumers. Lower fuel consumption by lighter vehicles will reduce both CO2 emissions and fuel costs for consumers. In addition, by lowering crash energy in the event of an accident, lighter vehicles are also potentially safer for both passengers and pedestrians. 

Other regions - notably the US, the world’s second largest car market - already use vehicle footprint as the metric for fuel economy. Not only does this improve fuel economy, it drives R&D into applications for lightweight materials in vehicles and accelerates their uptake. This is an area where Europe currently holds the technological edge and it should remain a strategic priority for the European car industry if it seeks to retain leadership.  

Encouraging lightweighting ticks many boxes for Europe’s environmental ambitions. Therefore, the revision of regulation 2009/443 is a huge opportunity for Europe. By taking this opportunity to encourage lightweighting, it will not only accelerate progress towards its own emissions targets but will maintain Europe’s pre-eminence in researching and deploying lightweight materials in transport. 

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