[Grover432]

Originally Posted by HighlandPete

The European (NEDC test) system is due an overhaul, it's a hot potato as it is related to emission targets and will mean a revaluation on all government and car manufacturers targets, as much as revised fuel consumptions. Reading an article on the subject just yesterday and it appears the current proposals will still be a compromise, as reality seems a step too far for most bodies involved to stomach.

We are now seeing above a 15% average mpg shortfall for the UK, many cars over 20%.

HighlandPete

I think it's pretty simple to set ratings. Give me a car and let me urban drive it in all types of urban commute scenarios for a week in the summer, fall, winter and spring so that all weather in the year is accounted for. I'll promise to drive gently (no sudden starts, no high speed driving, etc). I'll report what I get, then we can move on to a highway test.

For all the engineers out there who complain about the methodology; I bet at the end of my test, my numbers will more closely approximate what the actual average fuel consumption of the car is likely to be than any government test the auto manufacturers (yes you read that right, the auto manufacturers) can come up with. I'd bet money on it!

[HighlandPete]

Originally Posted by Grover432

I think it's pretty simple to set ratings. Give me a car and let me urban drive it in all types of urban commute scenarios for a week in the summer, fall, winter and spring so that all weather in the year is accounted for. I'll promise to drive gently (no sudden starts, no high speed driving, etc). I'll report what I get, then we can move on to a highway test.

For all the engineers out there who complain about the methodology; I bet at the end of my test, my numbers will more closely approximate what the actual average fuel consumption of the car is likely to be than any government test the auto manufacturers (yes you read that right, the auto manufacturers) can come up with. I'd bet money on it!

I know what you are saying, but I have to put my engineers hat on... we have to have a set of tests which can be replicated for all vehicles, both for independent and comparison testing.

Where I have a problem, the current NEDC test (for Europe) is not representative of real world driving. Set up tests which truly reflect what is achieved on the road, (from average data) there should be close to parallel results, if the official tests are not skewed by error, or by some external interest or bias. So easy to optimise a test over time, rather than be seeing true averages.

For example, it is known for the NEDC test that the road load figure which gets used for the dyno test, is now questioned for integrity, as it is not reflective of independent tests. Clearly the existing data is favoured by the manufacturers as it is biased towards good results.

None of this helps the user who often sees poor consumption, compared to expectations.

HighlandPete

[Grover432]

Originally Posted by HighlandPete

I know what you are saying, but I have to put my engineers hat on... we have to have a set of tests which can be replicated for all vehicles, both for independent and comparison testing.

Where I have a problem, the current NEDC test (for Europe) is not representative of real world driving. Set up tests which truly reflect what is achieved on the road, (from average data) there should be close to parallel results, if the official tests are not skewed by error, or by some external interest or bias. So easy to optimise a test over time, rather than be seeing true averages.

For example, it is known for the NEDC test that the road load figure which gets used for the dyno test, is now questioned for integrity, as it is not reflective of independent tests. Clearly the existing data is favoured by the manufacturers as it is biased towards good results.

None of this helps the user who often sees poor consumption, compared to expectations.

HighlandPete

There is no question that a representative test can be set up, but the interests of the manufacturers seem to be more important than accurate testing methods to provide consumers with accurate data.

There is allot at stake for manufacturers. Kia recently had to settle a class action suit for putting up consumption figures that were 20% lower than actual. The smaller car companies may not have the capital (or want to commit the capital) to invest in technologies that will reduce fuel consumption. But they have to sell cars, so Kia took a chance and got caught.

All the car manufacturers benefit from test rules that show unrealistically high fuel economy. If it was that difficult to devise an accurate test, don't you think there would be some cars that got better mileage in the real world than the government fuel economy ratings? Its curious that all of the cars do poorer on the road than in testing (and never the other way around).