Methods and systems are provided for controlling a temperature of gases within a heat exchanger, a ratio of gases output by the heat exchanger, and selectively charging/discharging gases from the heat exchanger to one or both of an intake system or an exhaust system. In one example, a method may include controlling operation of an energy recovery device coupled to the heat exchanger in response to engine operating conditions, and increasing or decreasing flow of exhaust gas and/or compressed intake air into the heat exchanger in response to energy recovery device output.