BRUSSELS, March 12 (Reuters) - Belgian electricity company SPE said on Wednesday it had bought 635 megawatts of nuclear energy capacity from Suez's Electrabel, boosting its share of Belgium's nuclear market to some 15 percent.
SPE, partly owned by Gaz de France and Britain's Centrica, said it was a three-part deal.
It bought 285 megawatts of supply until at least 2025, in the first part, then a further 100 megawatts of capacity in exchange for capacity from a plant at Chooz in France. The final 250 megawatts will result from acquired capacity from Electrabel's Belgian nuclear plants.
An SPE spokesman said the transaction would be effective from the summer. It would mean SPE would possess 10 percent of Belgian nuclear power capacity and have rights to a further 5 percent.
Its share of the Belgian electricity market would increase to around 11 percent from 9 percent currently.
No financial details of the deal were disclosed.
The transfer is related to Suez's merger with Gaz de France, which is seen taking place by the end of June. Gaz de France is obliged by regulators to sell its indirect stake in SPE.
Belgium wants to have at least three major players in its energy market.
(Reporting by Philip Blenkinsop; editing by Rory Channing)