Tire manufacturer Michelin this week held its almost annual international forum on sustainable mobility in Rio de Janeiro. The event, called the Challenge Bibendum, offered a busy schedule of round-table discussions, debates and demonstrations—but ultimately the tire company is interested in what happens when the rubber hits the road.
Calculating the costs and the payback for a more expensive tire is also tricky.
The sustainability question is a major issue for Michelin and other tire makers. The number of cars in the world is expected to grow from 900 million today to 1.5 billion or more by 2030, according to Michelin research and development chief Terry Gettys. As a result the company has set the goal of reducing the mass of tires by 50 percent by that time. In this way, the carbon footprint of tires will not grow along with the number of vehicles on global roads. But how do you reduce the mass without sacrificing safety, durability or ride quality?
One way is to change the overall shape of tires by making them exceptionally tall and narrow, or fat and short. In Rio, Michelin showed prototypes of two such odd-looking tires, which may be off into the future—if consumers would ever accept such a novel approach.
The more immediate and practical challenge is reducing rolling resistance, especially in support of hybrid and electric cars. Low rolling resistance helps hybrid cars go further on a gallon of gas, and helps pure electric cars extend their range.
Hybrid and EV owners are motivated to go with low resistance, but the engineering challenge is not unique to those vehicles. Terry Gettys, director of the research and development process of the Michelin Group, said, “Fundamentally, designing tires for electric vehicles is not different than for vehicles with engines.” He said that car manufacturers are looking for new tires tuned to electric drive and urban environments, but that design fundamentals “are not changed.”
The Challenge Bibendum has been running for 12 years, and apparently this kind of future-looking event and research has paid dividends—both for the company and consumers. Consumer Reports continually puts new tires through its tests, and recently gave high marks to the Michelin Energy Saver A/S. It ranked second overall—with only one tire getting higher marks: the Michelin HydroEdge.
According to the U.S. Department of Transportation, rolling resistance accounts for about 4 percent of a vehicle’s fuel use in city driving and about 7 percent on the highway. The DOT says that replacing high-rolling resistance tires with low resistance can result in about $100 in annual fuel savings-and potentially hundreds of dollars over the life of the tire.