| 777 | Date: Saturday, 30 Oct 2010, 14.18 | Message # 1 |
|
Like Sharing
Group: User
User ID: 777
Joined: 18 Oct 2010
Messages: 1035
| People are becoming ever more aware that tires make a difference when it comes to a car’s fuel economy. According to the Environmental Protection Agency, 5 to 15 percent of a car’s energy output is gobbled where the rubber meets the road. As the wheels turn, the flexion of the rubber creates waste heat. This is called rolling resistance, and the more resistant your tires, the more fuel it takes to travel each mile. Tires with lower rolling resistance are getting more popular, and there are discussions on the state and national levels to put efficiency ratings on tires similar to the mpg stickers on new cars.
Michelin has been selling low-rolling-resistance tires since 1992 under the Energy Saver name, and it says these tires have saved nearly 49 millions gallons of fuel and prevented 500,000 tons of carbon-dioxide emissions, suggesting that even small gains in efficiency can add up big.
Until now, high-efficiency tires haven’t been visually distinct from their conventional cousins. But Michelin used this year’s Challenge Bibendum in Rio de Janeiro as an opportunity to showcase two new conceptual tire designs, both of which break the mold we’re used to.
One is dramatically smaller than anything we now see on modern cars. Michelin’s experimental 10-inch wheel is short and fat (think the original MINI Cooper), but Michelin says the stubby wheel offers the same handling as a 14-inch wheel. And although the small tire feels the same to drive (never mind the peculiar appearance), it is low-rolling-resistance and uses less material, and so can reduce the weight of a car by 85 pounds, while increasing the car’s load capacity by 15 percent.
Michelin is also rethinking the wheel in the opposite direction: a very tall and narrow design. Specifically engineered for electric and hybrid cars, Michelin’s other concept tire is notably tall and thin. Making the tire tall further reduces rolling resistance (less flexion as the wheel turns), while making it narrow makes the whole car more aerodynamic (between 1 and 3 percent of a car’s aerodynamic drag comes from the tires themselves).
Recognizing that the number of cars on the planet is expected to double by 2030 — with most of this growth in large cities — Michelin has laid out some ambitious goals to reduce its tires’ energy consumption, noise output and raw material content. Michelin also aims to cut the carbon-dioxide emissions of the cars that use its tires by roughly one gram per kilometer each year. At the moment, neither the short and fat nor the tall and thin prototype is ready to hit the market, but they offer a hint of where we might be headed.
| HTML code to this post |
|
| BB code to this post |
|
| Direct link to this post |
|
|
| |
| |
Member: 5095 
Forum: 2322
News: 27
Blog: 16
Downloads: 18
Comments: 5