Heidelberg, Germany - Europe's first heavy-ion accelerator specially designed to destroy cancer tumours requires as much electricity to run as a town of 10,000 people, the doctor in charge said Friday.

The Heidelberg Ion Radiation Therapy Centre (HIT) is to treat 1,300 patients with brain tumours and other difficult carcinomas annually. German health insurers have agreed to pay the enormous bill of 20,000 euros (30,000 euros) for each session.

Marc Muenter, the head doctor, said a test system already built in another German town had brought at least five years of extra life for 80 to 90 per cent of the 450 patients it had treated.

In the centre of the new building is the 670-ton heavy-ion gantry, a 13-metre diameter ring that accelerates heavy ions and protons up to three quarters of the speed of light before they slam into tumours.

The only comparable devices are two in Japan, neither of which are inside hospitals, the doctors said. Germany aims to build two more, and Italy is constructing one in Milan, making six in the world.

Senior politicians will be on hand at the inauguration in Heidelberg on Monday.

The device, which has a power uptake of 3 megawatts, will be staffed 24 hours a day to ensure it is kept spotlessly clean, since dust could cripple it.

The radiation beam can be directed more accurately than the X-rays conventionally used against cancer. Tests are continuing so see which ions are most effective: those of carbon, oxygen or helium.

Physics professor Thomas Haberer who headed the design team said the machine was comparable in its complexity with the world's biggest passenger aircraft, the Airbus A380.

A more accurate device prevents damage to healthy brain tissue and reduces the unpleasant side effects of cancer therapy, the medical team said. (dpa)