What next for fuel economy testing?

With the annual MPG Marathon finishing earlier this month; the Peugeot 208 Active Blue HDI winning it with a very impressive 104.5 MPG (almost 20% higher than its official best return), it serves to highlight that, under the right conditions, cars can outperform their quoted fuel economy figures by quite significant amounts. However, most of the "real world" MPG tests submitted by motorists to any number of comparison sites show that fuel economy returns, most of the time, are well below those quoted on official documents.

So what do we believe? The official tests at least give us a fairly standardised set of benchmark results in which we can compare performance across what appears to be a level playing field. But even then it isn't level. The whole VW dieselgate episode has served to underline that certain manufacturers are willing to cheat the official tests, and whilst the VW group's defeat devices seem to have been designed to cloak emission levels, we can't be certain the device wouldn't have had an effect on official MPG returns too. Even if this was a one off, many other manufacturers, quite legally it would seem, supply cars for the tests which have been "aided" to complete the best possible returns, namely the stripping out of anything which adds unnecessary weight to the car. Although how a vehicle's wing mirrors or door handles, according to some reports, cannot be classed as "necessary" is slightly baffling.

The only way to get a true MPG reading for your vehicle is of course to drive it yourself and see what you can achieve, obviously not feasible though when looking to compare vehicles before a purchase decision. The next best option is to get the information from drivers carrying out similar driving scenarios to yourself i.e. the real world MPG as mentioned above. However, there are even more variables at play here than the official tests which means giving any more credence to these figures could be a false economy, if you'll excuse the pun.

One thing is clear, the whole thing is a bit of a muddle, but at least the emissions scandal has put the whole testing of new vehicles under the spotlight, and perhaps the resultant fallout will mean a more representative test will be created. Until then, it's up to the motorist to decide whether they base their decisions on the official test results, review the real world returns, or just ignore them both and buy the car they want regardless. We'd probably suggest a bit of research and a healthy mix of all three.

Labels: Dieselgate, fuel economy, MPG, MPG testing, Real MPG

posted by AJ @ 20:37