California power companies have an appealing but flawed argument with the state’s goal of 100% clean energy by 2045. They want existing dams that churn out carbon free electricity to count toward that mark, making it easier and cheaper to meet their climate friendly obligations. A pending bill, SB386, sounds narrow and focused, but it’s not. It would allow the Modesto irrigation district that operates Don Pedro Dam astride the Tuolumne River to total the cranked out electricity toward its renewable energy quota. That exemption would mean less need to buy juice from solar, wind and other green sources and save money for ratepayers.