Disclosed is an energy collector system applicable to internal combustion engines. It may include: a) a collector of thermal energy from the exhaust gases; b) a thermal tank covered by helical tubes to gain heat by the exhaust gases; c) a heat exchanger; and d) an outer element capable of converting thermal energy into mechanical energy, such as a closed Brayton cycle turbine, a Stirling engine, a Rankine turbine or an open loop air motor for converting mechanical energy (coupling the difference in rpm) into electrical energy with an electrical generator. The thermal energy collector may be composed of a heat exchanger that collects energy from the exhaust gases. The electrical energy generated may be used for driving a hybrid vehicle. The thermal tank is capable of storing energy as heat, as well.