Hanover, Germany  - When the Hanover Fair, the world's principal exhibition for industrial machinery, opens next week, one of the principal talking points will be ways to save scarce energy.

Machinery that thumps metal, extrudes plastic or pumps air through pipes consumes vast amounts of electricity, and engineers are looking for ways to both cut factory power bills and help fight global warming.

Sepp Heckmann, chief executive of the April 21-25 fair, says the three big trends in the sector are miniaturization, the greater use of intelligent devices and a focus on energy efficiency, not just to save power but also to raise productivity.

Industry experts believe there is "immense" potential for industry to save energy, but not using traditional technologies.

Some 5,100 companies from 62 nations will be exhibiting at the fair, which has sections devoted to energy-saving, automation, pipelines and other technologies. For the first time it will have a power-plant technology section.

As it happens, these businesses are a key to Germany's ability to keep exporting even in times of world economic turmoil.

The story from German exporters in recent months has been that full order books show that not even the rising cost of steel and other materials, the giddying run-up of the euro or portents of global recession are reducing world demand for industrial plant.

February figures from the VDMA, Germany's plant manufacturing federation, showed export orders up 9 per cent, year on year, and domestic orders up 12 per cent. The sector employs 935,000 Germans and has 180 billion euros (286 billion dollars) in annual sales.

VDMA chief economist Ralph Wiechers explained why: even though sales to the dollar zone have been weakening, the orders keep flooding in from emerging economies like China and India as well as from Arab nations and Russia.

The Germans forecast their plant exports will grow 5 per cent this year after 11 per cent in 2007 in real terms.

This year's Hanover Fair will be special because the partner nation will be Japan, another giant in industrial machinery.

A former Japanese prime minister, Shinzo Abe, will show up in Hanover Sunday evening to ceremonially open the event with Chancellor Angela Merkel, and 150 Japanese companies have booked booths.

Tomoharu Washio, deputy chief of the Japan External Trade Organization (JETRO), said in Hanover recently that Japanese business people were expecting new contacts and closer ties to Germany, with the two countries having much in common.

The power-saving theme of the Fair will be highlighted in the Energy Efficiency Tunnel, a showcase of ideas.

One of the solutions is adapting pumps so they can vary their speed.

Rudolf Duerrschmidt, a marketing executive at Danish pump maker Danfoss, explains, "When you reduce revolutions per minute by an average 20 per cent, you can reduce a pump's energy use by up to 50 per cent."

Currently, only about one-tenth of pumps used in industrial production have speed adjusters. Most run flat out all the time.

"What would you think if nine out of every ten cars on the road had their accelerators pressed to the floor and the drivers were controlling the speed with the brakes?" asked Duerrschmidt.

Danfoss and ABB Automation Products will be demonstrating in Hanover ways to slow pumps when full power is not needed. That could reduce energy use for a pump by up to 70 per cent.

Other parts of pumps can be improved too. Out among the booths, British company Compair will be demonstrating a compressor that has a magnetic bearing that practically eliminates friction and oiling.

"It can run at 60,000 revolutions a minute, no problem," the company said of the bearing, which uses the forces of magnetism to separate surfaces.

Factory ventilators are another big power waster. Scientists working for Germany's Fraunhofer Institute say Europe's factory fans consume 86 terawatt-hours of electricity a year.

Save one-third of that and you could dispense with four big coal-fired power stations.

Friedhelm Loh, president of the ZVEI federation of German electrical manufacturers, puts it another way: using technologies showcased in the Tunnel, all commercially available, industry could save power equal to 40 per cent of that used by private households.

The problem, factory owners say, is that piecemeal improvements to old technology only bring small energy savings. Often it can be better to rip out machinery and install a new plant from scratch. (dpa)