 Duke Energy Corp. DUK, 0.19 subsidiary Duke Energy Progress has filed for an increase in the fuel costs used to generate electricity used to power homes and business in South Carolina, which if approved would boost residential electric bills in South Carolina by an average of 8.3, or 10.15 per month. The utility company said it made the filing with the Public Service Commission of South Carolina, as part of an annual adjustment of actual costs, and said it makes not profit from the fuel component of rates. 