A modular LED lighting system, comprising a coordinator module comprising a coordinator microcontroller electrically coupled to a coordinator communication circuit; a slave module comprising: a slave microcontroller; a slave communication circuit for communicating with the coordinator communication module; and a driver circuit for supplying power to one or more electrically connected LED lights; wherein the slave microcontroller is operable to automatically determine a loading of any LED lights electrically coupled to the driver circuit and in response cause the driver circuit to deliver an appropriate current to the LED lights from a selected power source, the power source being selected by the coordinator microcontroller from one of a solar powered source and mains powered source based on one or more predefined power selection rules evaluated by the coordinator microcontroller.