The power of tires for energy efficiency
Silica helps vehicles consume less by making tires last longer
Premium SW, Solvay’s new grade of silica, contributes to reducing CO2 emissions from cars and trucks. It also improves the lifespan of tires, thus reducing costs and resource consumption. As such, it is an integral part of our array of solutions that contribute to improving resource efficiency across a wide range of industries.
Precipitated silica, based on silicon dioxide (most commonly found in nature as quartz), is a crucial element in the highly complex composition of tires. Silica is what gives tires strength and resistance and is therefore instrumental in modifying their properties, especially when it comes to rolling resistance (tougher tires adhere to the road less) and durability (they wear out much more slowly).
This is a market Solvay has been involved in for a long time through its Silica business unit. And the environmental benefits of using the right grades and right quantities of silica have long been recognized. “Thanks to our decades of experience, we’ve been able to fully understand the effects of silica on the properties of elastomers and rubber,” explains Bruno Jestin, Global Business Director for the tire segment at Solvay Silica.
In 2019, Solvay launched its latest grade of silica, Premium SW, which takes these properties one step further. Tests have shown it enables 25% lower rolling resistance, with the direct benefit of reducing fuel consumption and therefore CO2 emissions by 7%. In effect, switching to a high-performance grade of silica is one of the cheapest and most efficient ways of cutting CO2 emissions from vehicles. If the 80 million new cars sold every year worldwide were equipped with green tires manufactured with Premium SW, the amount of CO2 they generate would drop by an estimated 11 million tons.
High-performance silica improves the tire’s structural resistance, enabling better tread wear performance.
But how does it work? “By improving rolling resistance, silica decreases the effort the motor has to make,” explains Bruno. “Less energy is transmitted from the tire to the road, decreasing fuel consumption as well as emissions.”
Premium SW is made of very small particles with a very high surface; they improve the mechanical properties of the rubber because their high surface area offers more contact points between the tire’s polymer and the silica. “This improves structural resistance by eliminating fragilities in the tire due to the presence of larger particles,” explains Thomas Chaussée, Global R&I Application Manager at Solvay Silica. “Consequently, lower silica contents are required to achieve superior resistance, which enables weight reductions – and that in turn diminishes rolling resistance.” This was the main focus for Silica’s teams in order to answer manufacturers’ demands, as they are under strong pressure to reduce the CO2 emissions.
Promising benefits for electric vehicles
At the moment, Premium SW has latched on especially in the truck and “off the road” markets (which covers tires for construction and mining vehicles, as well as tractors). “Thanks to its specific wear benefits, Premium SW offers better resistance in poor road conditions, offering lowest rolling resistance to regions like India,” continues Thomas. “It should also support the emergence of new ultra-low rolling resistance tires for the electric vehicle segment, without compromising tread wear.”
As it happens, the advantages offered by Premium SW are particularly relevant in the case of electric cars. Because they are heavier and have more powerful accelerations than thermal engine cars, electric vehicles tend to cause more tire wear, so switching from classical silica to more durable Premium SW tires makes perfect sense. What’s more, with their reduced rolling resistance, high-performance silica tires enable the car’s battery charge to keep rolling longer, a major commercial argument for manufacturers.
Tires that last as long as cars
As mentioned, in addition to better rolling resistance, tire longevity is the second major benefit of Premium SW – in fact, the ‘SW’ stands for ‘super wear:’ you can keep your tires on your wheels longer.
This is good news for any car owner, but even more so for rental services who manage large fleets of cars. With cities cracking down on individual car traffic, these types of companies are on the rise and looking for ways to reduce their maintenance costs: not having to change the tires so often, or even at all, is one way to achieve that. “Tires today can last as long as 60 to 80,000 km, thanks to their long-lasting performance enabled by silica,” says Bruno. “Our next target is tires that will last for 250,000 km!”
Consequently, stronger tires don’t disseminate as much waste. Instead of wearing off into the environment, the rubber stays longer on the tires. By enabling lower resource and energy consumption and reducing emissions, better tires have multiple positive impacts on sustainability, making high-performance silica a true enabler for a greener world!