The City shall have the power to buy, own, sell, construct, lease, maintain, operate and regulate public services and utilities and to manufacture, distribute and sell the output of such services and utility operations. The City shall not supply any utility service outside the city limits, except by written contract. The City shall have such regulatory and other power to own, operate, control and regulate utilities and all public services, and the use and occupancy of the public streets, property and right-of- way, or is not inconsistent with state law.