The company was founded in 1909 as Delaware Power & Light, which served Delaware. In 1943, Delaware Power & Light acquired Eastern Shore Public Service Company, which served the Eastern Shore region of Maryland and the Eastern Shore region of Virginia. The name of the company was changed to Delmarva Power & Light in 1966 and Delmarva Power in 1972. In 1994, Delmarva Power announced it would acquire the Conowingo Power Company, the Maryland retail electric subsidiary of PECO Energy Company that served 35,000 customers in portions of Cecil and Harford counties, for $150 million. This acquisition was completed on June 19, 1995.