For every single car that eats fossil fuels and emits greenhouse gases (GHGs), there are four tires propelling it down the road. Car owners know buying tires eats away at their pocketbook, but tires do more than just consume cash. The manufacture, distribution and disposal of tires contributes to pollution, and consumes rubber trees.
Tire manufacturing depletes 70 percent of the world’s natural rubber. Natural rubber comes from Hevea brasiliensis, the rubber tree; 93 percent of the trees are grown in Asia, which increasingly needs rubber trees to preserve rainforests.
Rubber trees aren’t the only resource involved. Tires also contain synthetic rubber to make up for the scarcity of the real stuff, and you need crude oil to make synthetic rubber. You also have to use crude oil or natural gas to make carbon black, a polymer additive that gives tires their color. So, crude oil and energy consumption are involved in every aspect of a tire’s life, contributing to a large carbon tread-print.
Manufacturers rely on carbon-consuming and -spewing vehicles to import rubber, not to mention the energy it takes to make rubber. Shipments of carbon black consume crude oil, as does the product; ditto for synthetic rubber. Finally, the tires are shipped to retailers, and they don’t necessarily end up on eco-friendly cars.
That last factor is the major pollution-producer. Tires create drag on vehicles, and those that cause too much friction in an effort to ensure traction and durability cause vehicles to burn more fuel than necessary; researchers attribute about 86 percent of GHGs from tires to rolling resistance. To combat this, manufacturers began making low rolling-resistance tires. They’ve also been experimenting with sustainable materials – everything from soybeans to rice husks that can replace petroleum-based ingredients.
In an effort to take tire sustainability to new heights, in 2016 South Korean manufacturer Hankook Tire opened a futuristic research and development center near Seoul called the Technodome. What’s unique about the Technodome is its focus on sustainability: According to the company’s website, the LEED-certified facility is made from recyclable building materials, includes a water-saving facility, and is powered by geothermal, solar and an “energy recycling facility”— a high-tech area with advanced insulation that converts natural light into usable energy. Special parking spaces are reserved for fuel-efficient cars, and the remainder of parking is in the basement, which reduces thermal island effect.
Like the Technodome’s emphasis on high-tech architectural engineering solutions, Hankook is focused on making tires with advanced technologies to promote sustainability. The Enfren Eco, for example, has a special silica compound and bespoke design to maximize fuel efficiency. It’s the stock tire for the Ford C-MAX Energi PHEV, a plug-in hybrid that achieves around 104 mpg in the city. The silica in the tire is a sticky, rubber-like substance made from sand micro-particles. It can replace synthetic and natural rubbers and makes for great traction without a lot of rolling-resistance. Hankook claims the Enfren has the best gas mileage rating in Europe, Japan and Korea.
But while Hankook is working hard to build sustainability into its product, the company faces stiff competition from other tire giants that manufacture and distribute their product worldwide. Bridgestone, the world’s largest tire and rubber company, wants to achieve 35 percent emissions reduction by 2020, and 50 percent reduction by 2050. Bridgestone is pioneering the use of guayule, a desert shrub that requires very little water, to replace rubber trees. Results are mixed — guayule doesn’t yield nearly as much rubber as trees. While both Bridgestone and Cooper have succeeded in making concept tires entirely from guayule, a lot of work needs to be done to cultivate enough of the shrubs to make a large number of tires.
On the broader sustainability front, Bridgestone also maintains 10 wildlife habitats near its tire plants and has achieved zero waste to landfill at several American sites.
Meanwhile, Michelin competes with Hankook on the LEED certification, and was able to reduce carbon emissions from its operations by 20 percent between 2005 and 2011.
For an upstart that wants to compete for the sustainability throne through application of advanced technologies, the competition is stiff for Hankook, but this competition is a good thing — and not just for tiny players. Although the U.S. is no longer a part of the Paris Accord, South Korea is — and Hankook is one of many examples of companies that might help keep U.S. manufacturing on its toes. As long as highly competitive companies in all industries around the world keep pushing toward sustainability, U.S. companies will continue to do so as well, or they’ll get left in the dust.