The UK government has just launched an index ranking cars according to their fuel efficiency.

It is designed to help people decide what new vehicle to buy, allowing them to search according to categories such as supermini, family, estate, and so on, alongside specifics such as transmission and fuel type.

To give an extreme example, shoppers can see that a VW Polo Blue Motion emits 99 grams of CO2 per kilometre, while a 3-litre Nissan Patrol 4×4 spews out 288.

The initiative is the latest addition to the government’s Act on CO2 campaign, which started earlier this month. The main plan so far seems to be an advertising onslaught designed to ‘introduce the concept of a personal carbon footprint’. But, there is also an online personal CO2 calculator and tailored advice on how to reduce environmental impact.

According to a new report on the UK Climate Change Programme launched last week, government policy to reduce emissions is based on a three-pronged approach of carbon pricing, technology policy and ‘removing the barriers to behavioural change’. The car index is clearly part of the third.

Of course, while all efforts to improve the tools available to people to cut their environmental impact, the government must be sure to put its own house in order. The single biggest contributor to UK greenhouse gas emissions is still the power sector. And until thorny issues around power generation are resolved it will continue to be so.

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