Onboard heater of auxiliary systems using exhaust gases and associated methods

A method of recovering energy from exhaust gas of a gas turbine engine of a mobile power system, the method comprising:

• operating the gas turbine engine mounted to a trailer, the engine having an intake port and an exhaust duct;
• opening an inlet duct in fluid communication with the exhaust duct to divert a portion of exhaust gas flowing from the exhaust duct to an exhaust energy recovery system (EERS) mounted to the trailer such that:
• the exhaust gas flows through a first heat exchanger of the exhaust energy recovery system to transfer heat from the exhaust gas to fluid of a first heat distribution reservoir mounted to the trailer;
• and
• the exhaust gas returns through the exhaust duct of the engine via an outlet duct of the EERS, the outlet duct being in fluid communication with the exhaust duct downstream of the inlet duct;
• and
• flushing the exhaust energy recovery system including:
• verifying the inlet duct is closed;
• and
• injecting a fluid into the exhaust energy recovery system when the inlet duct is closed to purge the exhaust energy recovery system.