Abstract: The power system for extending the effective range of an electrical vehicle including a non-polluting power generating mechanism for recharging the battery system during vehicle use and providing sufficient electrical energy to an electric motor for constant speed cruising without draining the battery system. The additional power needed for acceleration and hill climbing is provided by a temporary draw on the battery system, and by an increase in the RPM of the heat engine when needed. When the need for additional power is over, the power generating mechanism again recharges the battery system while it provides the energy necessary for continued steady state operation. The power generating mechanism comprises a non-polluting heat engine which is mechanically coupled to an alternator or a generator and a control network for controlling the heat engine and selectively directing the electrical energy generated by the heat engine to the vehicle's electric motor and/or battery supply.