Maritime Electric supplies electricity to customers in Prince Edward Island. Although the utility does have some electrical generation facilities, since the mid-1970s the majority of Prince Edward Island's electricity has been purchased from NB Power and supplied via an interprovincial electrical interconnection. This interconnection consisted of two 138 kilovolt oil-filled submarine transmission cables installed 1975-78 under the Northumberland Strait at the western end of the Abegweit Passage between Murray Corner, New Brunswick and Fernwood, Prince Edward Island. Since the Northumberland Strait freezes in winter, the cables were designed to be protected from ice scouring and were copied from a Swedish design that was originally used to supply the island of Gotland in the Baltic Sea. They were replaced in 2017 by two new cables providing a capacity of 300 MW.