Cost over-runs may double the cost of a world project to build a new kind of nuclear reactor that leaves behind practically no nuclear waste, according to the deputy chief scientist on September 15. The 5.5-billion- Euro ITER project, run by the European Union, the United States, Russia, China, Japan, India and South Korea, is building a fusion reactor to generate electricity in Cadarache in southern France. The final cost will exceed the budget by at least 10 percent and perhaps 100 percent, Deutsche Presse-Agentur (dpa) quoted Norbert Holtkamp, deputy director of the project, told a conference in Rostock, Germany. He told the fusion technology conference that reasons for the over-run included the higher costs of raw materials and energy as well as sophisticated new technologies that scientists want to include. Octavi Quintana-Trias, an official from the European Commission, said the EUwould pay 50 percent of the cost of ITER, which would demonstrate that a fusion nuclear reactor was feasible. In fusion reactors, atoms in a very hot gas fuse together, releasing energy. The heat from stars such as the sun is created in this type of nuclear reaction.