Business Green: An applicant for a new nuclear reactor in Maryland was last week purchased by a subsidiary of Warren Buffet’s Berkshire Hathaway group. Constellation Energy Group agreed to sell all its outstanding shares to Buffet’s MidAmerican Energy Holdings Company (MEHC) in a deal worth $4.7bn in cash and $1bn in stock. Constellation had applied to the Nuclear Regulatory Commission to install a third reactor at its Calvert Cliffs, Maryland, nuclear power plant. The application was lodged …