According to a recent survey, 46 per cent of large UK firms already have a green IT strategy in place.

There are two ways to interpret this statistic. The first is to herald it as evidence that in just a few short years the idea of energy efficient, environmentally-friendly IT equipment has already entered mainstream corporate thinking and that IT departments are taking their green responsibilities seriously and genuinely seeking to cut their carbon footprint.

The alternative is to ask what, exactly, have the other 54 per cent of firms been doing with themselves? Do they like wasting money or is it just that their desire to antagonise environmentalists is so great they do not mind burning cash in order to do so?

The fact is that every company should have a green IT strategy. Or to put it another way, no company should have a specific green IT strategy, on the grounds that as long as they are adhering to best practices and have a competent IT manager then their IT operations should be a pretty deep shade of green already.

The most commonly quoted green IT statistic is that globally the industry is responsible for two per cent of emissions, putting it on a par with the aviation sector. In developed economies, the situation is worse still with UK government figures claiming three per cent of the UK's electricity is consumed by server farms alone.

Meanwhile, as global PC ownership continues to boom and the amount of data stored by companies such as Google and Yahoo grows exponentially the sector's carbon footprint looks set to expand.

And yet, despite this seemingly intractable problem the IT industry is blessed with the fact that it is one of the few sectors where commercial and environmental considerations are almost perfectly aligned in both the short and long-term.

Taking energy as the most obvious example, IT departments should always be looking for the most energy efficient technologies they can lay their hands on. The premiums they have to pay for such systems are pretty minimal and the savings are huge. It might take a renewable energy project developer a decade to claw back their return on their investment, it will take a company buying the most energy efficient servers or PCs they can find less than 18 months.

In this context, the reduction in carbon emissions is a happy by product of thousands, and in some cases millions, of pounds worth of energy savings.

Again, you have to ask what those businesses that fail to consider energy use when making IT purchasing decisions are thinking, particularly given that most servers and PCs are so commoditised that there is little difference between rival models in terms of price and performance. It really is a no-brainer to demand that every piece of kit you buy is amongst the most energy efficient available.

This same alignment of commercial and environmental considerations is evident in almost every aspect of a company's green IT strategy.

Even when you look at the vexed topic of disposing of IT equipment there is a strong business case for taking an environmentally responsible approach, even before you consider the sad reality of PCs being shipped to illegal scrap yards in Africa where workers strip down the machines in dangerous conditions.

According to a new report from industry analyst Gartner, companies can expect to generate a profit margin of between $10 and $50 by selling machines they no longer want to the second hand market, and yet only 44 per cent of PCs are ever re-used.

For companies with fleets of 1,000s PCs that is a sizable revenue stream that is being ignored every time they send their three year old PCs for recycling, or worse still to the dump.

Even if they can't be bothered with the hassle of wiping the data from their machines there are charities such as Computer Aid International that will do the job for them and make sure their PCs find a valuable home in schools and hospitals in Africa, Asia and South America.

And as Computer Aid's chief executive Louise Richards explains there is a sizable environmental advantage to this approach. "As much as 75 per cent of the fossil fuels consumed over the entire life cycle of a PC have already been consumed before a PC is even switched on for the very first time," she says. "So, given the high environmental cost of production, we should be looking to extend the life of our PCs as much as possible."

In addition, when machines do eventually die the fact that resource constraints mean that commodity prices will only rise in the long term means there is a strong commercial case for recycling and reusing as many of the equipment's components and metals as possible.

Ultimately, it is the desire to make this recycling process as cheap and easy as possible that is fueling the industry's drive to engineer out toxic components, almost as much as the desire to halt Greenpeace's criticism of those manufacturers that continue to use hazardous chemicals such as PVCs and BFRs.

Faced with these relatively simple business realities it is apparent that those 50 per cent of IT departments that are still ignoring environmental issues are not just lacking a green IT strategy, they are without a decent IT strategy full stop.