Electricity bills will increase by about $2.64 per month for the average household customer in Emera Maine’s former Bangor Hydro Electric service starting Wednesday, as the company raises its rates for delivering power.
Power rates for customers in the company’s northern and eastern Maine Public Service district, however, are expected to drop by about 93 cents for the typical residential customer.
The rate change moves the company’s transmission charges from about 2.6 cents per kilowatt hour to about 3.3 cents per kilowatt hour for residential customers.
The average increase from the transmission charge was estimated assuming a household using about 380 kilowatt hours of power per month.
The increase in costs are tied to a formula set by the Federal Energy Regulatory Commission that may fluctuate depending on costs for operating and maintaining the transmission system.
The transmission systems for Maine Public Service and the former Bangor Hydro are not connected, which is why their rates can move in opposite directions.
The Northern Maine Independent System Administrator runs the Maine Public Service and Eastern Maine Electric Cooperative grid, while Bangor Hydro is connected to the regional ISO-New England grid. There have been a few proposals for connecting the two.
Emera Maine in April proposed transmission line rebuilds for the next five years totaling about $114 million for its Bangor Hydro service area and about $61 million for its Maine Public Service area.
The PUC earlier this month opened an investigation into those proposed projects, which regulators estimated could eventually cause transmission rates to rise to around 5.26 cents per kilowatt hour.
The commission wrote the investigation will focus on “how Emera Maine got to the point where such a large part of its transmission system would need to be rebuilt in such a short period of time.”
The company’s distribution rates rose in 2014 for the first time since July 2008 in the Bangor Hydro territory. The change comes as the supply portion of bills has gone down for those getting the standard offer price for power.
Prices for power supply dropped about 8 percent in March but will be put out for bidding again this fall, with new supply prices that would take effect Jan. 1, 2016.