Abstract: A system for supplying steam to a well casing for secondary oil recovery from an oil well includes an individual electric steam generator unit positioned at the ground surface adjacent each well head. The steam generator includes an electrode assembly comprising a pair of concentrically spaced cylindrical electrodes positioned between a pair of electrically insulative end plates and mounted within a cylindrical, closed-end electrically insulative housing by electrically conductive rods extending through the respective electrodes and the end plates and secured to one end of the housing. The end plates are spaced from the ends of the housing to form a water inlet space at one end of the housing and a steam outlet space at the other end. Apertures in the end plates communicate the water inlet space and steam outlet space with the space between the electrodes. The apertures communicating the steam outlet space may be skewed to provide a turbulent flow of steam into the steam outlet space.