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  • What is the true environmental cost of your vehicle?

Steel can reduce greenhouse gas emissions during production, use and recycling, the life cycle assessment (LCA) approach demonstrates

Cars create emissions at all phases of their life – from production of raw materials to recycling at end of life. Yet existing legislation on vehicle emissions in Europe focuses only on the use phase of the vehicle’s life. This pushes carmakers to reduce the weight of their vehicles, but at the same time encourages them to utilise materials which may have high emissions during the production phase, and which may have limited or no recycling benefits at the end of the vehicle’s life.

The three phases of a complete life cycle assessment


The use phase of a vehicle’s life accounts for between 50 and 90% of its lifecycle emissions, depending on the fuel source used and the powertrain. The graph below shows that, while this is significant, the contribution of the production and recycling phases are becoming more important as use phase emissions are reduced.

LCA emissions for different powertrain types (European energy mix)


Why does LCA matter?

An LCA covers production of the raw materials, use of the product, and its end of life including recycling and reuse. It enables manufacturers and material suppliers to accurately evaluate the potential environmental impact of their products or materials over their life cycle.

Using LCA to quantify emissions from vehicles shows that steels, and in particular advanced high strength steels (AHSS), have the potential to significantly reduce life cycle greenhouse gas (GHG) emissions. Development of AHSS and technologies such as laser welded blanks (LWBs) ensure that the right steel is in the right place. This enables manufacturers to achieve significant weight reductions.

Alternative to conventional steels

AHSS is an excellent substitute for conventional steel as it reduces the environmental impact of vehicles during the production and use phases of their life.

Materials such as carbon fibre reinforced plastic (CFRP) have very high levels of GHG emissions during the production phase. Up to 4 times higher than steel for Aluminium and up to 6 times for CFRP.

Production phase emissions for different materials - kilograms of CO2-equivalent per kilogram of material (source: www.worldautosteel.org)


When it comes to end of life, there is almost no industrial recycling capacity for materials such as CFRP. While the European Aluminium Association claims a recycling rate of around 90%, different studies of the end-of-life shredding process for vehicles show that the aluminium recycling rate is actually between 60 and 70% in practice.

100% recyclable steel

As most steel is magnetic it is extremely easy to extract from waste streams, ensuring that about 96% of steel is recovered and recycled. Steel does not lose its properties during recycling.

Steel’s recycling properties also make it an excellent material to comply with the European Commission’s End-of-Life of Vehicles (ELV) Directive which dictates that by 2015, 85% of the materials in a vehicle should be reused or recycled.

Reducing emissions from the automotive sector requires a full picture of the emissions produced during all phases of the material’s life. Only through accurate LCA can the true environmental benefits of steels become clear.

Read the full article in the May 2013 issue of the Update client magazine