GEORGIA — State regulators on the Public Service Commission on Tuesday approved a Georgia Power plan to source more energy from burning wood known as “biomass,” despite criticism from consumer advocates about its relatively hefty price tag. An independent evaluator found the trio of contracts for which the monopoly utility was seeking approval would cost customers two to three times more than other sources of energy. The biomass proposal had been opposed by environmental and consumer advocates, who said it would cost Georgia Power customers billions of extra dollars on top of already-approved rate hikes. …In hearings about the biomass proposal over the past few weeks, regulators acknowledged the high cost for Georgia Power customers, but said they were motivated by a desire to give an economic boost to rural parts of the state that rely on the timber industry. The vote Tuesday was 4-1 in favor.