Senate Minority Whip Michael J. Hough (R-Frederick) tried a new approach Wednesday in his years-long effort to change the official state classification of a controversial renewable energy source. After failing last week to attach an amendment to a bill that would have stripped fuel generated by Maryland’s two waste-to-energy plants from qualifying for tax breaks under the state’s renewable energy portfolio standard (RPS), Hough on Wednesday used a different piece of legislation as a vehicle for an amendment to downgrade fuel produced from trash as a clean energy source.