Few business people will have missed the increasing prominence of environmental concerns lately. But as my colleague James Murray has pointed out, it's easy to get caught in a pincer movement that squeezes out all hope. On one side, corporate initiatives to improve matters are often dismissed as a veneer with little substance; and on the other, the scale of global CO2 output is such that any single project to amend matters will make so little difference that it is not worth the bother. Only governments, by vague means of emissions targets, seem to have the power to do anything.

I prefer to think that every little helps. I don't care if a plant-a-tree carbon-offsetting scheme won't do all it's supposed to, it has to be better than doing nothing.

IT managers wanting to make a difference face two problems. Firstly, corporate bean counters won't wear purchases made on the basis of a fondness for hugging trees. This is why the WEEE directive is welcome, because it connects green issues to concrete cost factors. But the bigger problem is that environmental impacts are very hard to quantify. By analogy, look at the choice facing a green-minded car buyer.

For some people, conscientious motoring requires a car like the Toyota Prius, which can run on batteries when creeping along in traffic jams and on petrol plus battery power at other times, giving it an official CO2 figure of just 104g/km.

However, the choice is not so clear cut. Recently, US-based analyst firm CNW Marketing Research measured the environmental cost of cars from the base of the supply chain to the scrap-yard. This "dust to dust" calculation revealed that a modern car with good fuel economy can be bad news if it has to be shipped halfway round the world, is built from large numbers of complex components, and uses highly refined and processed materials.

According to CNW, these hidden factors mean that an apparently highly inefficient vehicle – the Jeep Wrangler 4x4 – is actually the greenest car Americans can buy. It is built locally, to an old-fashioned design and slack tolerances, using low-grade materials. These factors easily compensate for the Jeep's lazy 4-litre engine, despite it emitting more than three times as much CO2 per mile as a Prius.

The car industry is squabbling fiercely over the validity of CNW's research, but the issue is relevant to all products that market themselves as a green choice. How is an IT manager to know the dust-to-dust deficit behind a Sun server?

This, however, is where governments can help. They may procrastinate over big, long-term problems, but they are absolutely great at mandating and enforcing fiddly accounting rules.

I'd like to see our government expend some of its bureaucratic brainpower on the problem of measuring total energy costs of products, and to force vendors to make this data available to buyers.

Of course, this effort would no-doubt waste forests of paper, require endless meetings attended by car and aeroplane, and would make life harder for everyone. But I think, nonetheless, it would be a big step in the right direction.