The City shall possess and hereby reserves to itself all the powers granted to cities by law to acquire, construct, own, operate, improve, enlarge, extend, repair and maintain, either within or without its corporate limits, including, but not by way of limitation, public utilities for supplying water, light, heat, power, gas, sewage treatment, and garbage disposal facilities, or any of them, to the municipality and the inhabitants thereof; and also to sell and deliver water, light, heat, power, gas and other public utility services without its corporate limits as authorized by law.