LONDON — EDF Energy, the British subsidiary of the French state-controlled utility, said on Monday that it was shutting down three nuclear reactors and that a reactor with a fault that has been shut down since June would remain so. The facilities, which are being investigated as a precaution, generate nearly a quarter of nuclear capacity in Britain.

The British Office for Nuclear Regulation said that there had been no release of radioactive material and no injuries. Industry experts did not anticipate much effect on electricity supplies or prices in the short term.

EDF said that over the next few days it would idle a second reactor at the facility where the fault was found last year, Heysham 1, in northwest England. The company said it would also shut down two other reactors of similar design at Hartlepool in northeast England to investigate whether they had the same flaws.

The plants, including the one idled since June, will be closed for an estimated eight weeks while the inspections are performed, EDF said. The company added that it was “not possible” to know exactly when they would return to operation.