CIOs must respond to rising energy costs, said Gartner.

With server rooms growing and electricity costs rising, IT departments need to embrace energy efficiency to save the planet and money, according to Gartner.

The analyst said high-density servers were the main culprits for excessive energy consumption as they used between 10 and 15 times more power than traditional server environments.

Even worse, the energy costs doubled when you factored in all other aspects of a standard data centre -- including the air conditioning, storage devices and uninterruptible power supplies -- compared with the energy cost of the servers alone.

This would have a major impact on IT budgets in the future, said Gartner, with energy costs rising from less than 10 percent of the budget to more than 50 percent within the next few years.

But most CIOs will not be able to convince the board to simply increase budgets.

The potential to overspend on power will impact on the IT department's ability to grow and meet business needs in the future, Gartner predicted.

Instead, IT leaders must adopt "greener" approaches to data centres. The analyst advised CIOs to optimise use of existing equipment to delay moves to the high density systems that eat up the most power.

Vendors also have an important role to play in developing more energy efficient kit -- however, Gartner admitted much of the technology to limit power consumption would not be available within the next five years.