Abstract: An electrical heat exchange device comprising a plurality of electrically conductive metal plates secured side by side in spaced apart relationship by electrically insulating spacer means. Each of the plates has a plurality of conductive path sections formed therein so that current will flow along a predetermined elongated path through the plate. The plates have a plurality of perforations, at least along the elongated path for the passage of a fluid conducted therethrough under pressure whereby to heat the fluid by the plurality of plates. The perforations decrease the conductive cross-section area thereby increasing the electrical resistance of the plate. Electrical connectors are provided for connecting the plates in series with one another at opposed ends of the elongated path. Connectors are provided for connecting the series of plates to an electrical power source for heating the plates by joule effect.