Testing, testing

"The fleet market did not like this upheaval one bit"

- ILLYA VERPRAET

Both of our road test subjects this week are plugin hybrids.

According to the official WLTP figures, one does 256.8mpg, the other 282.0mpg. A Volkswagen Passat eHybrid even boasts 731mpg. There is some sense to these numbers. The way they come about involves something called a 'utility factor', which represents the proportion of total miles that a PHEV is likely to drive in electric mode - when it uses no fuel at all.

The actual numbers are furiously complicated, but in effect it boils down to this: if a PHEV with an electric range of 48 miles starts a 50-mile journey fully charged, then it will indeed use a minute amount of fuel. These figures are achievable if you religiously plug the car in and rarely do journeys that exceed the electric range.

But without any context, a reasonable person would look at them and rightfully conclude they are nonsense. Even with plenty of context, it's clear that most PHEVs do in fact travel significant distances using their combustion engines, and while they can be very fuel efficient when used as designed, they're not that fuel efficient in the real world. And that's before we consider the cost of the electricity used to charge them, never mind how convenient it might be to plug them in.