The six-day fair, which will open its doors to visitors Tuesday, this year focuses on environmentally-friendly computers and other information technology systems.

“When you look at non-travel power consumption in the world today perhaps PCs and IT are the most rapidly growing power consumers on the planet,” software giant Microsoft chief executive Steve Ballmer told a news conference.

According to German magazine Stern, global Internet usage needs the equivalent of 14 power stations to power the required computers and servers, producing the same amount of carbon emissions as the entire airline industry.

“We think we have a real responsibility … to reduce power consumption by the IT industry,” Ballmer said.

Cisco Systems Inc. manager Jan Roschek estimated that the IT sector is responsible for about 2 percent of the world’s carbon dioxide emissions.

At the opening ceremony, Ballmer declared a “fifth information technology revolution” in front of dignitaries including German Chancellor Angela Merkel, European Commission President Jose Manuel Barroso and French President Nicolas Sarkozy.

The new revolution will see tiny devices, huge computer storage, high speed connections and computers that interact with people in a natural way, Ballmer said.

This year, the CeBIT tech show is built on three pillars, namely Business Solutions, Public Sector Solutions and Home & Mobile Solutions, which are expected to offer visitors a preview of the future of the ever-changing IT industry with high-tech gimmicks, gadgets and stunts.

The fair attracted 5,845 exhibitors from 77 nations leasing booths to demonstrate software and new digital equipment, among which are 650 Chinese companies. For the second year, China ranked first among overseas exhibitors at CeBIT.

However, the total number of exhibitors decreased by 300 from last year. Big brands like Sony, Sharp, Philips, Lenovo, Dell and Nokia are not present at CeBIT this year.

Analysts said CeBIT is facing a really difficult time in asserting its position as the world’s largest tech fair. In Germany, the Games Convention and the Berlin IFA are luring its audience away, on an international level it faces competition from the Consumer Electronics Show in Las Vegas.