Methods and systems are described for providing a local electrical power source at a header of a combine harvester. An alternator is mechanically coupled to a header backshaft. The header backshaft is mechanically coupled to a drive mechanism of the combine harvester to cause rotation of the header backshaft which, in turn, causes the alternator to generate electrical power. A power supply circuit transferred electrical power from the alternator to one or more electric devices mounted on the header. In some implementations, the header does not include any physical cables between the combine and the header.