Duke Energy has filed a request with the North Carolina Utilities Commission for rate hikes that would give subsidiary Duke Energy Progress an additional $477 million a year. Duke Energy Progress has not raised rates since 2012. The utility’s request of 14% for households and 9% for businesses was approved by the utilities commission, but cut to an average of 5% by the state Supreme Court. Duke is now asking for what would amount to an average 14.9% average increase, with a typical residential rate increasing 16.7%, or $17.80 a month. Additional revenues would help pay for an $11 billion investment the company is making in converting plants to source natural gas and renewables over the next 10 years, $25 billion it is spending upgrading transmission systems to accept input from renewable generators and ward off cyberattacks, and $5.1 billion needed to remediate coal ash ponds. Duke’s other NC subsidiary, Duke Energy Carolinas, will likely request its rate increase later in the year.