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While vehicle manufacturers are looking at the various ways and means to reduce carbon emissions, one place that they might consider, assuming the vehicles in question are large, commercial vehicles, is not under the hood but within the tires: the wheels.
Alcoa (alcoa.com) has released a peer-reviewed, life-cycle assessment (LCA) of the use of forged aluminum wheels in place of steel wheels that finds that by replacing the steel wheels on an 18-wheel truck to aluminum, 16.3 metric tons of carbon emissions are reduced over the life of the wheels.
As this is an LCA analysis, and not just looking at the performance of the end product, data on energy and material consumption, green house gas and other environmental emissions related to the production of the wheels were taken into account. Primary data from five wheel plants (two in the U.S. and one each in Mexico, Hungary and Japan) were included. They even included the bauxite mining involved.
The study indicates that while aluminum wheels require more energy to manufacture than steel wheels, the reduced wheel mass and the recyclability of the wheel at the end of life (remember: this is the whole lifecycle) mean that there is a CO2 break-even at 205,000 miles, then energy and CO2 savings accrue after that point.
The study was conducted by PE International & Five Winds Strategic Consulting (pe-international.com).