A system for transmission of data and electrical power comprising: a plurality of independent power sources, each one of the plurality of independent power sources being connected to a respective one of a plurality of electrical power lines; and a modulator configured to modulate a carrier signal with a data signal received at an input of the modulator so as to generate a modulated carrier signal at an output thereof, wherein the output of the modulator is coupled to each of the plurality of electrical power lines, to permit transmission of the modulated carrier signal over the plurality of electrical power lines, such that the plurality of electrical power lines form a data network while maintaining electrical isolation between each of the plurality of electrical power lines.