Should cars advertised with green credentials be advertised with laboratory fuel economy figures?

In your reply "Juke bucks jury" you highlight the discrepancy between laboratory fuel economy results and reality. The example showed an 80 per cent higher consumption than the laboratory and also, presumably, 80 per cent worse emissions. Accepting that this might be a means by which equality for the purposes of comparison is achieved for cars generally, is it really appropriate for vehicles specifically marketed on their green credentials, such as the Toyota Prius Plus also featured in the paper to be presented with bogus figures? Do you not think that people buying cars with their environmental conscience are entitled to realistic figures?

Asked on 21 April 2012 by PH, Orpington

Answered by Honest John
Our point is to counter the flawed EC tests with reality. The tests are the basis for taxation so cannot easily be changed (even though there is talk of it). But we have collected the real life experiences of more than 17,000 drivers and collated them into a usable databank at www.honestjohn.co.uk/realmpg.

There are now signs that the EC might review its economy and emissions testing criteria to make them more realistic, but it could not retrospectively change the registered emissions of hundreds of millions of EC vehicles already certified.
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