Whenever any rate of any public service company chartered by or organized under the laws of this state exists or is charged pursuant to charter, contract or any agreement or understanding, and is in whole or in any respect discriminatory or more or less than just, reasonable and adequate to provide properly for the public convenience, necessity and welfare, such company or any town, city or borough within which, or between which and any other town, city or borough in this state, any such company is furnishing service, or any ten patrons of any such company, may bring a written petition to the Public Utilities Regulatory Authority alleging that such rate is discriminatory or more or less than just, reasonable and adequate. Thereupon, the authority shall fix a time and place for a hearing upon such petition and shall mail notice thereof to the parties in interest and give public notice thereof at least one week prior to such hearing. Upon such hearing, the authority may, if it finds such rate to be discriminatory or more or less than just, reasonable and adequate to enable such company to provide properly for the public convenience, necessity and welfare, determine and prescribe just and reasonable maximum rates or charges to be thereafter made by such company.