The European Commission and the US Environmental Protection Agency have signed an agreement with Energy Star to ensure computers, printers and copiers sold in the European Union and US will be more energy efficient.

The new agreement is expected to save a total of 22 terawatt hours (Twh) over the four- to six-year lifetime of home and office equipment - roughly equivalent to Ireland's total annual energy consumption, the Commission said.

The list of machines currently approved under the EU and US Energy Star scheme includes 70 desktop PC brands, 43 laptops and tablet PCs, 18 copiers, 32 printers, 19 scanners and 14 fax machines.

"The new criteria are an important contribution to reach the EU's energy efficiency targets," said the European energy commissioner Andris Pielbags.

Computers are expected to account for most of the savings: 18 TWh out of the 22 TWh target, the Commission said.

The EU and US Energy Star scheme will in future be extended to cover other product categories including servers, data storage equipment and video games consoles.