Nearly half of firms have a green IT strategy, and another quarter plan to devise such a plan in the next two years.

But 35 percent of those with a strategy already in place do not expect to make cost savings in the next year, according to a new IDC survey of 459 IT directors in large businesses across Europe.

The survey, part of the first IDC Green IT Barometer, found that the U.K. is "well above" the European average for green initiatives, but behind Germany where half of the businesses were estimated to have a green plan.

In the U.K., large businesses spent 5.5 percent of their IT budget on green initiatives, but IDC expects this to reach eight percent in two years.

Cost pressures drove the uptake of green initiatives, the survey said, despite some of the firms with existing initiatives questioning resultant cost improvement. Regulatory concerns were another key factor.

James Quarles, EMEA director of solutions marketing at Dell, which sponsored the research, said: "Green isn't just good for the environment, it's good for the bottom line, and that message seems to be getting through loud and clear in the U.K."

But Nathaniel Martinez, lead analyst at IDC, said green IT plans "won't always yield immediate tangible benefits". He said it was vital that organisations effectively measured the energy efficiency gains resulting from green IT investments.

This was a challenge for many firms, IDC said, with 34 percent lacking proper metrics for measurement, and 42 percent complaining of a lack of guidance from the IT industry.