Abstract: A solar power supply for a spacecraft comprises an array of semiconductor devices for photovoltaic conversion of sunlight into electrical energy. Each semiconductor device is secured by a substantially stress-free electrically conductive joint to a flexible dielectric substrate that can be folded into a compact stowage configuration or opened into an elongate operational configuration. The stress-free joint is formed by securing an electrical terminal of the semiconductor device to a stress-relieving electrical conductor that is affixed to the substrate. Preferably, the stress-relieving conductor is a metallic wire mesh, a peripheral portion of which is adhesively bonded to the substrate circumjacent an aperture in the substrate. A pattern of metallic traces formed on the substrate provides a circuit for connecting the wire mesh to connectors for coupling electrical power generated by the array of semiconductor devices to an electrical load on the spacecraft.