Ohio Rev. Code § 715.34: Hot water and steam heating.

Any municipal corporation may use, or by ordinance grant, for periods not exceeding twenty-five years, the use of its streets, avenues, alleys, lanes, and public places to lay pipes, conduits, manholes, drains, and other necessary fixtures and appliances under the surface thereof, to be used for supplying such municipal corporation and its inhabitants with steam or hot water, or both, for heat or power purposes, or both.

In all such grants the municipal corporations shall reserve the right to regulate, at intervals of not less than five years, the prices which the grantee may charge for such heat or power.