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What is Your car’s Real MPG Figure?

Every motorist is extremely conscious of fuel costs these days and this is a major factor when considering the purchase of a new car. Prospective car buyers paw over the brochures and online information to compare the fuel consumption figures of cars in their chosen sector.

Every motorist is extremely conscious of fuel costs these days and this is a major factor when considering the purchase of a new car. Prospective car buyers paw over the brochures and online information to compare the fuel consumption figures of cars in their chosen sector. No one can deny that the car industry has made impressive strides in the last few years and official fuel consumption figures are reaching levels that were scarcely dreamed of only a couple of decades ago. This is reflected in figures just released from the EU that show carbon dioxide emissions for cars sold in Europe have fallen to an average of 127g/km. This means that the industry has already met and exceeded its target to cut emissions to 130g/km by 2015. The figures would also indicate an average fuel consumption figure for new cars sold in the EU of 56.5mpg. 
 
 But just how accurate are these figures? According to the Transport and Environment group in Brussels (T&E), the answer appears to be ‘not very’. In fact, their figures show that motorists in the UK who buy new cars could be looking at fuel bills that are as much as 25% higher than the official figures would lead them to believe. Furthermore, the huge differences are not the result of error but are in fact due to car makers cheating the system. Instead of an average of 56mpg, T&E group contends that the real figure is more likely to be 45mpg. 
 
Greg Archer, clean vehicles manager at T&E, explains: “Fuel efficiency standards are being undermined by an obsolete test. The test procedures are a Swiss cheese, full of loopholes that carmakers exploit to exaggerate improvements in fuel economy and emissions.”
 
Car manufacturers claim that the real value of these laboratory tests is to allow buyers to make a reasonable comparison between models, rather than to obtain an accurate measure of real-world fuel economy. T&E, however, dismiss this argument and say that the loopholes are such that car buyers can’t even compare different models. They highlighted manufacturers’ tricks during testing, which include setting the wheel on edge to give less contact between tyre and road (something that would be completely unsafe in practice), taping over the gaps between body panels to reduce wind resistance and using extremely sophisticated and expensive ultra-low friction lubricants in the gearbox and engine that would never be used by real consumers. 
 
The T&E group’s findings follow on from a report in 2012 by the Dutch motor testing organisation, TNO, which also confirmed that manufacturers used such techniques. Manufacturers have been doing this to establish their car’s ‘road load curve,’ which is then used in the computer settings for rolling road tests in the lab. Consequently, the car achieves better MPG and CO2 emissions figures during the test. 
 
The European Commission has been aware of the problem for some time and plans to introduce a new test in 2017 to tackle these issues. This new globally applied test will be designed to give a more accurate picture of real-world driving performance but it is being opposed by car manufacturers. T&E claims that manufacturers have been lobbying for the new test to be delayed until 2022, which is after the date that carmakers must meet the EU target of average 95g/km emissions or be hit by heavy fines. One strategy in achieving this figure is to lower the average by selling more electric cars, which have zero exhaust emissions and also get ‘super credits’ from the EU, which can be used by the manufacturer to offset emissions of normally-fuelled cars. 
 
According to a European Environment Agency report, in the UK, the average emissions figure for new cars sold in 2013 was 128.3mpg, which places the country very close to the overall average. The agency’s figures also showed that the average new car in Europe had a power output of 119hp with an average engine size of 1.6 litres, with diesels having an average of 1.8 litres and petrol-engined cars at 1.4 litres. According to the manufacturers themselves, CO2 emissions fell by 17% between 1990 and 2012.

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