Synergy is facing new revelations it has overcharged West Australians for power. (ABC News: Cason Ho) More than 170,000 customers have been overcharged a total of $40 million by WA's state-owned energy retailer Synergy since 2009, it has been revealed. The overpayments range from amounts under a dollar, to thousands of dollars, according to Synergy CEO Kurt Baker, who said most of those affected were residential customers. "We've accepted payments to approximately 170,000 closed accounts, resulting in overpayments," he told ABC Radio Perth. "In many cases this has happened because Synergy's allowed customers to continue to pay to their closed...