Green Car Congress  
Go to GCC Discussions forum About GCC Contact  RSS Subscribe Twitter headlines

« New BMW 1-Series Features New Gasoline and Diesel Engines; Start-Stop and Regenerative Braking Standard | Main | Vacaville (CA) Promoting Honda Civic GX and Home CNG Refueling »

Print this post

Study: Under-inflated Tires in the EU Waste 8.1 Billion Liters of Fuel Each Year

8 March 2007

An estimated 93.5% of motorists in the EU are driving on under-inflated tires and causing an additional 18.4 million tons of carbon dioxide to be released into the environment, according to a recent analysis by Bridgestone Europe. That works out to an extra 6.9 g CO2/km for every car on Europe’s roads.

Based on the data collected in 2006, Bridgestone also estimates that 40% of vehicles consume an additional 2.8% in fuel due to their under-inflated tires, wasting 8.1 billion liters (2.14 billion gallons US) of fuel every year.

To collect data for the study, Bridgestone conducted free safety checks on 20,300 passenger cars in 19 EU countries during 2006. Only 6.5% of motorists had all tires correctly inflated, 54% had some degree of low inflation and 39.5% had at least one tire significantly under inflated (<1.5 bar or 21.8 psi). 12.0% of cars (1 in 8) were in danger of tire failure.

The free check-ups were conducted by Bridgestone at shopping centres and public car parks. They form part of the “Think Before You Drive” safety education campaign, a worldwide joint initiative between the FIA Foundation (Fédération Internationale de l’Automobile), Bridgestone Corporation and national motoring clubs, launched in 2005.

These results suggest that many motorists are unaware that a tire loses pressure naturally over time, like a balloon, and that driving on incorrect pressure can be dangerous. The loss of handling control and increase in vehicle drift rises sharply as tire pressure is reduced. Low tire pressure also has an extremely negative effect on tire durability, due to excessive shear stress in the shoulder and heat build-up from sidewall bending. The 12% of motorists identified with seriously low tire pressure face possible tire failure due to these factors.

The wear life of a passenger car tire is halved if pressure falls from 2.2 bars (32 psi) to 1.0 bar (14.5 psi). Based on this 2006 survey, Bridgestone’s Technical Centre Europe calculates that the almost 40% of motorists at risk are losing 19.3% of tire wear life—an average of 9,700 km or 9 months of tire usage (based on an average wear life of 50,000 km and annual mileage of 13,600 km).

A further 54% of vehicles are losing 5.2% of tire wear life; an average of 2,500 km or 2 months of tire usage. Adding these two groups together shows that 24.5% of tire wear is being lost through under-inflation in Europe.

Inflation pressure has a strong influence on tire 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.

Tire pressure sensors are one mechanism the EU is exploring in bridging the gap between the 130 g/km CO2 target and the 120 g/km per vehicle goal in upcoming legislation mandating CO2 limits. (Earlier post.)

March 8, 2007 in Fuel Efficiency, Tires, Vehicle Systems | Permalink | Comments (19) | TrackBack (0)

TrackBack

TrackBack URL for this entry:
http://www.typepad.com/services/trackback/6a00d8341c4fbe53ef00d834fba9d353ef

Listed below are links to weblogs that reference Study: Under-inflated Tires in the EU Waste 8.1 Billion Liters of Fuel Each Year:

Comments

There is no doubt in my mind that this is the single most overlooked item on cars today. Before radials came out it was obvious by just looking at the tire if it was low....but no more. Fortunately, at least here in the States, all cars must have a low tire indicator as of '07, I believe.

This is either baldfaced obvious, or I'm blowing the chance at a billion-dollar patent: Make tire filler-caps that contain a MEMS based pressure gauge and turn RED when underinflated. That would make it obvious to you and everyone else you were wasting fuel and polluting more than necessary.

This in tandem with fuel-tax subsidized compressor hoses at every gas pump should alleviate the problem in a jiffy.

Bud, it's MY2008 but that's still better than us Europeans. Some manufacturers, e.g. VW, offer tire pressure monitors (based on ABS sensor analysis) as an available option but it's not yet mandatory. If the EU proposal of 130gCO2/km fleet average + 10 more saved via biofuels & tire pressure monitors becomes law, car makers may make them standard items even before it takes effect in MY2012.

http://www.cbsnews.com/stories/2005/04/07/tech/main686326.shtml

BlackSun -

such devices already exist, here's an example. The point is few people bother installing them, let along checking them regularly. For the masses, you want something that activates a warning light on the dash.

http://www.autobarn.net/kle44444.html

Most gas stations charge for air, making it less likely people will use them. They are also usually on the side of the building. If there were compressors along side the pumps, it would GREATLY increase the % of properly inflated tires. Instead of just waiting for the pump to stop, they can pump up their tires while they wait.

I'm not sure how economically feasable it is though. Do you have to bury compressed air lines from each pump into the actual station's master compressor? Do you install individual compressors at each pump? That's more likely since their is electricity already at the pump. The big problem though, is compressed air creates water condensation and this will freeze up the pump in colder weather.

I used to manage a carwash that had one of the few free air pumps in town. We had a large compressor for the car wash anyays, so a line was run out the side of the building for little cost. However, anytime the weather was about 15 degrees F or colder, that line (not the inside compressor) would freeze and become inoperable. How would the compressor itself handle the cold?

Personally, I wish my car had the onboard air pump like my father's car. That is a sweet little accesory to have in the corner of the trunk. Of course I do have one in the garage, as any good shade tree mechanic does.

Wally's World offers a $10 portable A/C that plugs into cig lighters... Cord could be longer, but it's held up o.k.

I just use my bicycle pump for my car tires...it isn't that difficult, saves electricity, and is cheap.

Finding air and carrying around a roll of quarters is just too inconvenient for me (compared to using my hand pump).

I would HATE for there to be any compressors right next to gas pumps. Fumes from gasoline + initial startup for compressors (sparks across the coils on the motor) = big boom. Unless they design an intrinsically safe approved contraption for the air compressor (probably only making the cost of an air compressor 10 times the normal price).

Hmm, if cars start using tweels instead of rubber tires, wouldn't this factor be taken out of the equation for gas mileage???

Actauly they are thinking of tires without air at all.

I'd calculate
(40% @ 19.3%) + (54% @ 5.2%) = 10.5%.
This is compared to their erroneous 19.3+5.2=24.5%. So do you believe the rest of what they say?

Inflating tires at gas station is no good: tires should be inflated while cold, and usually gas station compressors have very inaccurate gauges.

Small tire inflator (about 2lb) working from 12V cigarette lighter socket could be bought under 20$ in every hardware shop with automotive department. I strongly suggest also to buy very accurate piezo gauge for about 10$. Maintaining precise tire pressure requires about 5 minutes once a month. I usually do it on Saturday morning, when tires are cold after overnight parking.

I also carry the inflator in the trunk of my car, together with tire repair kit. At least once a year I repair nail fractured tires for cars in my family or occasionally for friends. It takes about 15 minutes without taking out the wheel from the vehicle, anywhere on the road or wilderness. For two dozen tires I’ve repaired it was only one occasion when tire sidewall was penetrated and I have to use the spare.

Fine tuning tire pressure on the spot when I drive high at the mountains, or on loose sand is additional bonus of having my inflator always with me.

P.S. Recommended for particular vehicle tire pressure is written on the sticker attached in the front door arch (driver or passenger side). For many vehicles recommended tire pressure front and back is different. Also do not forget to inflate high-pressure spare tire once in a while, or you will have it underinflated in exact moment when you will need it most.

I have always had 2,5 Bar / 2,3 Bar in front / rear tyres (0,2 Bar more than it should be). Fuel consumption is further reduced some 1-2%. Yes, just a little but top speed is also higher - 195km/h compared to 190km/h. (I have 1.8l / 94 HP '1994' Renault Laguna; awerage consumption is 6,3l / 100km or 37 mpg US - it's a gasoline version). I live in Slovenia (E.U.).

DB -

last I read, Michelin's Tweel is considered too noisy for automotive applications in its present state of development. Also, the aesthetics are radically different from conventional wheels and might put off some customers. Michelin might have to prove their safety in a racing environment first.

There would be advantages beyond never having to worry about tire pressure, though. By drastically reducing the unsprung mass, tweels would increase elastokinematic comfort and also save fuel.

Hi Yesplease,

For that very reason Gas pumps are air powered machines. So, the compresed air is already in the ground out to the pumps, to run the air motors in the pump.

All one would have to do is tap into the pneumatic plumbing inside the pump, and put a money slot on it. A buisness would need to charge money to make up for the lost time on the big investment (the pump).

For the guy who said you can't fill up your tires at a gas station, bologna. Do the following test: Check your tire pressures in your driveway/garage before leaving for work. Drive to work and see what your tire pressure is. That difference tells you how much to compensate your tire pressures when you fill up the tires "hot". If they go up 2psi, then fill to at least 2psi above the suggested cold rating. If they rise 4psi, then fill to 4psi above the cold rating. This is not rocket science.

Besides, the article states 40% have a tire at less than 22psi. Most manufacturers state tires should be 30psi or higher so if you get to the station and see a tire at even 24psi, its plainly obvious you need to add a lot of air. Having "hot" tires is not an excuse to never check your tire pressure.

Sid:

Inflating tires at gas stations is better than not inflating at all. Inflating it the way I do is better, plus some additional benefits. BTW, do not forget that temperature build-up in tire depends on distance driven, speed, traffic, or on major scale when it is raining. Plus terribly inaccurate gauges on gas stations (the ONLY accurate in practical use tire pressure gauge I am aware of is piezo).

NITROGEN! It leaves tires at 1/4th the rate of normal air. Also, it's dry, keeping the pressures more stable; no over-pressuring when hot, since the wator vapor is what expands. New cars (2007 models) trip the monitors when ambient temp changes significantly, making the new-car dealer service drives crazy; nitrogen prevents this problem.

Even Spalding recently introduced a new basketball (the Neverflat) with nitrogen and guarantees no inflation drop for one year.

I work for a firm that sells Nitrogen Generators for the truck industry; the technology is well proven in the airlines and the world of racing. Also, we sell an LED valve cap that flashes after a 4PSI drop. My wife loves the security of those!

Help! I've never learned how to inflate car tires with compressed air. I'm either afraid I'll blow the tire up or afraid I'll let all the air out when fitting the nozzle onto the valve.
I do own a nice pressure gauge, but it seems to let air escape when I use it, too, and I can see myself using it in the driveway and then having to drive to the gas station on a flat tire.

Closing Thoughts: You could have skipped the first 30 minutes of this show and missed very little of consequence. How hard could it be to either edit the promos out or do a new ad? The second half saved it with two memorable segments, the Anthony vignette and the promo by Daniels. The only good match was the tag bout. Barzini/ Lightning and O/ Crow were OK matches with lousy finishes. It never ceases to amaze me the way guys will put together a match with all kinds of moves and not take care to hit the most important one- the finish. There wasn’ t anything offensive about Green vs. Payne. But nothing especially good either. Green reminds me of Slim J (NWA Anarchy) at an early stage of development. Green should delete the Stinger splash from his repetoire- it’ s not a move most little guys lok good doing. Payne makes me think of 80s wrestler Doug Sommers. The announcers fawn over Steve O like he’ s a top level babyface. Based on the last two weeks, I don’ t get what they see in him, although his match this week was a big improvement. Airing promos for matches that aren’ t happening does not speak well for Main Event’ s quality control. Neither did the camera work on this show, as they missed two finishes. Today’ s fans have seen so much, it’ s tough for anything to generate a visceral response, but the Anthony vignette did it for me. There’ s a bizarre and twisted form of genius at work here– a truly memorable segment. I enjoyed Pearce’ s promo. As far as TV helping to draw crowds, Mike Sircy’ s biggest card of the year featuring the NWA World Title match had the benefit of ads on both SAW and Main Event and drew no better than they did the month before. The tag match had a very good finishing sequence. Falk worked his ass off again. There were points in last week’ s match where Falk appeared to be reach beyond the limits of his athletic ability, but not a problem this week. The Stevens/ Anthony brawl was not as effective as the clips of their brawl from the previous week. The action was fine, but the segment cried out for a second camera or a better angle or anything to get close to the action. I loved Daniels promo. The guy could always talk. The crucial thing was his personal guarantee of a violent stipulation match for the big show. This was the poor compared to the previous two Main Event shows.

Verify your Comment

Previewing your Comment

This is only a preview. Your comment has not yet been posted.

Working...
Your comment could not be posted. Error type:
Your comment has been posted. Post another comment

The letters and numbers you entered did not match the image. Please try again.

As a final step before posting your comment, enter the letters and numbers you see in the image below. This prevents automated programs from posting comments.

Having trouble reading this image? View an alternate.

Working...

Post a comment

Green Car Congress © 2013 BioAge Group, LLC. All Rights Reserved. | Home | BioAge Group