Plagued by electricity shortages, Bulgaria yesterday announced it was considering plans to reopen nuclear reactors it had to shut down before joining the European Union a year ago. The two Russian-made units at Bulgaria’s only nuclear plant, Kozloduy, were switched off just hours before the Balkan country joined the European Union on January 1, 2007. “We are holding active diplomatic talks to achieve the necessary support to prolong the life of Kozloduy’s units 3 and 4,” Prime Minister Sergei Stanishev said. He did not elaborate but said reopening the reactors was a “clear political choice of the government.” The move would require approval from the other 26 EU members.