Energy recovery system and method for automobile engine

The invention discloses an energy recovery system and method for an automobile engine. The energy recovery system for the automobile engine comprises an electric-control pump, a steam turbine, a condenser, a liquid storage tank, a controller, a pressure-limiting valve, an energy recovery mechanism, a first heat exchanger, a coolant temperature sensor, a second heat exchanger and a working medium temperature sensor. The coolant temperature sensor, the working medium temperature sensor and the electric-control pump are electrically connected with the controller. The energy recovery mechanism is installed on an output shaft of the steam turbine. The liquid storage tank, the electric-control pump, the first heat exchanger, the second heat exchanger, the pressure-limiting valve, the steam turbine and the condenser form a circuiting flow channel for working media. In the flowing process of the working media, heat of the engine is absorbed through the first heat exchanger and the second heat exchanger, and the energy recovery mechanism is driven by the steam turbine to recover energy. According to the energy recovery system and method, redundant heat of a cooling system and an exhausting system can be fully recovered, the energy utilization rate of fuel oil is increased, and meanwhile normal cod starting of the engine is prevented from being affected.