The board of public utility commissioners shall have power, after hearing, upon notice, to determine between public utilities supplying electric light, heat or power, and between a municipality and any public utility supplying electric light, heat or power within the corporate limits of such municipality, questions in dispute as to territories to be served. Pending the hearing the board may enjoin the construction of facilities for such supply.
Upon finding and determination that the construction is not necessary and proper for the public convenience and will not properly conserve the public interest, the board may issue orders prohibiting it.