PITTSFIELD >> A Canada-based power company with a plant on Merrill Road allegedly manipulated local energy markets, overcharging ISO-New England $3 million over two months in 2010, and the U.S. federal government now is seeking a $5 million fine against the company. Maxim Power Corp.'s Pittsfield plant fabricated a natural gas shortage between July and August 2010 then charged ISO-New England as if it was burning more expensive oil, according to the Federal Energy Regulatory Commission.