The Public Utilities Regulatory Authority shall by regulation require public service companies to file statements of their procurement policies and practices whenever there is a material change to such policies or practices. Where, after investigation, the authority determines that competitive bidding seems likely to reduce procurement costs without impairing quality, continuity or dependability of service or the ability to respond to emergencies, the authority may, after notice and public hearing, establish such regulations as it deems necessary to provide for competitive bidding in appropriate cases, but only if the contract price exceeds fifty thousand dollars in each such case.