Delmarva Power on Wednesday requested a $66.2 million electric rate adjustment that would increase the typical residential bill by about 15 percent.

The Salisbury-based utility said it needs the rate increase to recover the cost of system improvements and infrastructure upgrades that have helped reduce the frequency and duration of power outages. The request is subject to review by the Maryland Public Service Commission.

In a notice announcing the request, the utility said it has invested more than $330 million in its electrical system in Maryland since 2012 and last requested an electricity rate adjustment in the state in 2013.

The utility estimated that the monthly bill for a typical residential customer using 1,000 kilowatt-hours a month would increase by $21.42 to $168.84.

Maryland People's Counsel Paula M. Carmody called the proposed increase “unwarranted.” She said her office would hire consultants to examine the case.

Delmarva Power, a subsidiary of Exelon Corp. since it took over Delamarva's parent company Pepco earlier this year, has 203,000 electricity customers in Maryland, mostly on the Eastern Shore and in part of Harford County.

Exelon's other Maryland units also have received or are seeking rate increases this year. The Maryland Public Service Commission in June granted Baltimore Gas and Electric a rate increase that will raise the typical residential customer's monthly bill by about $7.53.

sarah.gantz@baltsun.com

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