Jennifer Granholm, the U.S. Energy secretary, said on Thursday that the Energy Department will aim to buy crude next month to help replenish stocks in the Strategic Petroleum Reserve. Granholm responded to a question during a hearing of the House Energy and Commerce Committee by saying that a sale of 26,000,000 barrels of oil, mandated by Congress, would be complete in June. “And it’s then at that point we will turn the switch and seek to buy.”