The utility made the request Friday to the Delaware Public Service Commission.
Delmarva Power says the $12.1 million request would increase a residential natural gas customer's bill during heating season by $8.67 per month. The increase would take effect in July 2013.
Delmarva Power has more than 122,000 natural gas delivery customers in northern Delaware.
This material may not be published, broadcast, rewritten, or redistributed.