Bridgestone inspected the tyre condition of 46,000 cars in 11 European countries in 2011. The results show that 63% of motorists are driving on under-inflated tyres. Bridgestone calculates that this habit is leading to the equivalent of 3.1 billion litres of wasted fuel worth € 5 billion a year. For the environment this means 7.4 million tons of additional and unnecessary CO2 emissions annually – the equivalent of an additional 2.7 g/km for every car on the road.
“As in previous years, the results indicate that a majority of drivers are unaware of the cost and environmental damage of failing to take care of their tyres” says Tom Fukuda, Senior Vice-President, Sales and Marketing, Bridgestone Europe.
These safety checks on more than 180,000 individual tyres were conducted by Bridgestone at shopping centres and public car parks as part of the company’s on-going tyre safety campaign activities.
Analysis of results show that 17.5% of motorists are driving on seriously under-inflated tyres (at least 0.5 bar below recommended pressure) and 4.3% are putting their safety at high risk by driving on severely under-inflated tyres (at least 0.75 bar below recommended pressure).
1 in 5 tyres should be replaced
Almost 20% of tyres on the road are also worn down below the E.U. legal minimum of 1.6 mm tread depth, representing an immediate safety risk to drivers of the vehicle, passengers and other road users. Drivers of these vehicles are likely to experience hydroplaning at speeds of up to 40% lower than normal and face a high safety risk due to loss of road grip.
Just over 3.5% of inspected tyres are both severely worn and severely under inflated, exposing the driver to double danger.
Low inflation pressure increases tyre rolling resistance
The results suggest that many motorists are unaware that a tyre loses pressure naturally over time, like a balloon, and that driving on incorrect pressure is not only dangerous but also wastes fuel and adds significantly to CO2 emissions. This is because inflation pressure strongly influences tyre rolling resistance, which is itself a key factor in determining vehicle fuel consumption. Depending on the type of road and driving style, rolling resistance represents 18% to 26% of the total force on a vehicle. Since low inflation increases rolling resistance, it has a direct effect on vehicle fuel efficiency and emissions.
Personal safety at risk
Driving on low pressure is also dangerous: as tyre pressure is reduced, the driver experiences a loss of handling control and vehicle drift rises sharply. Low tyre pressure also has an extremely negative effect on tyre durability, due to excessive shear stress in the tyre shoulder and heat build-up from sidewall bending. Motorists identified with seriously low tyre pressure face possible tyre failure due to these factors.
Bridgestone continues to promote greener motoring
In 2011 Bridgestone expanded its Ecopia range of eco-friendly car and truck tyres. Ecopia tyres contribute to the prevention of global warming by helping to reduce CO2 emissions through higher vehicle fuel efficiency brought about by lower rolling resistance. Thanks to Bridgestone’s new compound technology, Ecopia tyres achieve this lower rolling resistance without compromising grip and safety.
2005 8,700 vehicles checked in 10 countries
2006 20,300 vehicles checked in 19 countries
2007 38,867 vehicles checked in 19 countries
2008 31,178 vehicles checked in 14 countries
2009 52,400 vehicles checked in 15 countries
2010 38,200 vehicles checked in 8 countries
2011 46,000 vehicles checked in 11 countries
Key Results 2011
17.5% of vehicles checked were using seriously under inflated tyres (4.3 % severely under inflated)
Wear due to low inflation pressure
- 5% of tyres were both severely worn and severely under-inflated.
Tyre tread depth 6% of the tyres checked have 30% reduced mileage due to under inflation
19.7% of tyres checked had a tread depth below the legal level of 1.6 mm. Consequences for the environment due to low inflation pressure
19.1 million tyres are lost because of premature wear
18-26% of the total force on a vehicle comes from tyre rolling resistance
17.5% of checked drivers face significantly higher fuel consumption because of low inflation pressure
Because of under-inflation, € 5 billion and 3.1 billion litres are being wasted. This adds another 7.4 million tons of CO2 emissions
That's the equivalent of an extra 2.7 g/km of CO2 output, for every car on Europe's roads!