The governing authority of any county in this state may authorize the execution of one or more contracts which specify the rates, fees, or other charges which will be charged and collected by the county for electric, natural gas, or water utility services to be provided by the county to one or more of its utility customers. Any such contract shall be subject to the following conditions and limitations:

(1) No such contract shall be for a term in excess of ten years;

(2) Any such contract which is for a term in excess of two years shall include commercially reasonable provisions under which the rates, fees, or other charges shall be adjusted with respect to inflationary or deflationary factors affecting the provision of the utility service in question; and

(3) Any such contract shall include commercially reasonable provisions relieving the county from its obligations under the contract in the event that the county's ability to comply with the contract is impaired by war, natural disaster, catastrophe, or any other emergency creating conditions under which the county's compliance with the contract would become impossible or create a substantial financial burden upon the county or its taxpayers.