How green is your car? - The results in full

To make CNW's report meaningful to car buyers, all energy usage was turned into the amount of petrol needed to supply the same amount of energy; this was then translated into the cost of the petrol in dollars.

The research also included the average fuel consumption over the car's life based on real-world figures reported by more than half a million Americans.

This total figure was then divided by the mileage over a vehicle's life, which ranges from 151,000 miles for a small hatchback such as the Hyundai Accent, to 300,000 for a Toyota Land Cruiser.

The report's economy figures also reflect the deteriorating economy as cars age and their engines and exhausts wear out.

The most expensive vehicle is the Mercedes-built Maybach, whose total energy cost rates at the equivalent to £7.24 per mile, which compares with the Wrangler at 38p per mile.

To illustrate how different materials translate into different energy costs, CNW provides figures on the energy used to make the conventional steel in a 4x4, against the lightweight steels in a hybrid such as the Prius. According to the research, the steel in a Hummer H2 4x4 uses £125-worth of energy, less than the £143 for the steels in the Prius. The conventional steel is also easier to recycle.

The report goes on to say: 'Fuel efficiency is only a small part of the total energy needed to design, develop, produce, drive and dispose of a vehicle. In fact, some of the less fuel-efficient vehicles actually have extremely good 'dust to dust' energy consumption. Conversely some hybrids - at least the current hybrids - are inferior in total energy demands while offering high fuel-efficiency.

'This doesn't mean that hybrids, for example, are a bad choice. What it does mean, however, is that a modern hybrid uses less fuel and produces fewer tailpipe emissions, but costs society significantly more in overall energy costs.'

Click here to see the full table of results.