Atlantic City Electric on Friday filed a $61.7 million request with the state Board of Public Utilities to increase its rates, less than a year after being granted its previous rate increase.

A residential customer using the average of 1,000 kilowatt hours per month would see monthly bills rise by $9.57 if the filing is approved as requested.

The average monthly bill would be $179.91, a 5.6 percent increase from current rates, the Mays Landing-based utility said.

Such cases can take six months or a year and often result in negotiated settlements involving the state Division of Rate Counsel and the BPU that lower the increase sought in the initial filing.

In June, Atlantic City Electric, a subsidiary of Pepco Holdings Inc., received state approval to increase rates by about 3 percent after initially seeking about a 7 percent increase.

The U.S. Bureau of Labor Statistics said consumer price inflation in the region was 1.2 percent over the past year.

Atlantic City Electric Region President Vince Maione said Friday’s request represents money the utility spent — mostly in 2013 — for infrastructure and reliability improvements.

The utility said work included upgrading 140 feeders — high-voltage lines that distribute electricity, replacing 150 miles of wires with sturdier ones and installing automated switches on about 30 feeders that help isolate power outages.

The switches can detect short circuits and isolate them to minimize outages, Maione said, adding that the work has helped reduce power outages and their durations.

The devices cover about 10 percent of the circuits and are used in Atlantic County and portions of Gloucester, Camden and Salem counties, he said.

Maione said the utility hopes to expand them to other areas.

Friday’s rate request represents the distribution of electricity — what Atlantic City Electric charges to run and maintain the area grid. It does not reflect the price of electricity itself.

People who buy their electricity from third-party suppliers would be affected by this rate-increase request.

Atlantic City Electric has more than 545,000 customers in southern New Jersey.

A representative of the Division of Rate Counsel, which represents utility customers, was unavailable Friday to comment on the proposed increase.

In New Jersey, residential retail electricity costs about 30 percent more than the national average, according to December data from the U.S. Energy Information Administration.

Among the lower 48 states, New Jersey’s retail electricity costs were the eighth most expensive, after Connecticut, Massachusetts, New Hampshire, Rhode Island, Vermont, New York and California.

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