The International Thermonuclear Experimental Reactor (ITER) partners ended years of negotiation on 24 May, agreeing to start construction on the fusion reactor at Cadarache, France in 2007. Representatives from each of the seven partners gathered in Brussels to initial the agreement, green-lighting the project. The agreement will now go to national governments for ratification, and then a formal signing ceremony will take place, allowing work to begin next year. The project brings together the EU, China, India, Japan, South Korea, Russia, and the United States, together representing more than half of the world's population. The EU's Science and Research Commissioner Janez Potocnik signed the document on behalf of the EU, and highlighted how the partners are united in an ambitious attempt to investigate fusion as a new source of energy, in theory both green and limitless. Hosting the conference, Mr Potocnik declared that he and the other signatories were making history in two ways. 'We are making a historical decision on the search for energy and we are also making a historical decision on global cooperation. I hope that this will be a model for the future,' he said. The Cadarache reactor will reproduce the fusion reaction that occurs in the Sun and stars. When the nuclei of small atoms come together at very high temperatures, they fuse, producing huge amounts of energy. To recreate this effect on Earth, the reaction needs temperatures above 100 million degrees Celsius. At these temperatures, solid structures would be instantly vapourised. Powerful magnetic fields keep the particles away from the walls of the container to prevent any vaporisation, and to minimise heat loss. Fusion is highly attractive because it relies upon an unlimited resource - the raw materials can be found in seawater, it produces no greenhouse gas emissions, no radioactive materials need transportation, it produces no radioactive waste, and meltdown is not possible. Mr Potocnik was keen to emphasise that nuclear fusion does not have any of the risks associated with nuclear fission, such as explosions. 'It is a totally different story,' he said. If it works, fusion could provide the answer to the world's energy problems, namely the reliance on unsustainable resources such as oil and coal, and the harmful emissions produced when using fossil fuels. But it is a gamble, and an expensive gamble. The reactor will cost 4.57 billion euro to build, and will take ten years. Estimated operating costs over the 20-year expected lifetime, are expected to be around the same amount. As 'host party', the EU will contribute around 50 per cent of the construction costs, and the other parties will each contribute around ten per cent. The EU Commissioner believes that the investment, and the risk, are 'worth it', and the fact that six other parties have also signed up, after months of difficult negotiations, proves that they also believe in the project, he said. This is a 'potential answer' to current energy concerns, 'and if we truly get the answer, it will be forever,' he said. Asked by CORDIS News whether all EU Member States will benefit from ITER through EU's partner status, Mr Potocnik emphasised the benefits to industry, which he said would be spread across the EU. 'I think that people are underestimating how broadly industry will be involved, and how broadly the results will be used,' he said.