The commissioner may offer a centralized travel service to all state departments and agencies, and to the Minnesota State Colleges and Universities, and may, in connection with that service, accept payments from travel agencies under contracts for the provision of travel services. The payments must be deposited in the motor pool revolving account established by section 16B.54, subdivision 8, and must be used for the expenses of managing the centralized travel service. Revenues in excess of the management costs of the centralized service must be returned to the general fund.