BOSTON — The collapse of a regional pact to reduce tailpipe emissions sets back the state’s clean energy goals, according to environmentalists, who say Beacon Hill needs to find another way to cut the largest source of greenhouse gases. Last month, Gov. Charlie Baker pulled the plug on the Transportation Climate Initiative — an ambitious plan to create a multi-state pact to reduce transportation pollution — after the agreement failed to gain traction among other states.Baker had been one of the most vocal proponents of TCI, touting it as key to the state’s effort to reduce the largest source of greenhouse gas emissions.
Baker spokesman Terry MacCormack said in statement that while TCI is “no longer the…