NOVELTY - The system (100) has a generator (104) that captures heat from an exhaust of an engine. The generator configures the solution having solute that is vaporizable by heat captured by the generator. A condenser (108) is coupled to generator for receiving vaporized solute and condensing vaporized solute to liquid. An absorber (116) couples evaporator (114) and generator and configured to return solute to solution by mixing solute with solvent such as water, glycol and ammonia supplied to solution by generator. The solution returns to generator to complete cycle of system.    USE - System for capturing energy from heat expelled in exhaust of engine of motor vehicle such as truck.    ADVANTAGE - The system reduces the fuel consumption, emissions and is easier for drivers to comply with existing and/or upcoming anti-idling legislation is achieved. The systems can provide a life cycle cost that uses and stores the thermal energy directly with little or no operational penalty to vehicle operation. Thus the systems can use little or no fuel and the fuel consumption is reduced while driving. The condensers can optionally having a fan configured to pass air through the condenser and the efficiency of the condenser is increased. During a cold start of the engine allows the user of the system to pre-heat the engine before starting the engine. Thus the engine wear and emissions emitted by the engine are reduced during a cold start and allows the user to immediately use the vehicle heating system once the engine is started.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) method for operating in cold storage mode in system for capturing energy from heat expelled in exhaust of engine of motor vehicle and storing captured energy;    (2) method for operating in heat storage mode in system for capturing energy from heat expelled in exhaust of engine of motor vehicle and storing captured energy;    (3) controller for controlling in system for capturing energy from heat expelled in exhaust of engine of vehicle and storing captured energy; and    (4) heat exchanger for use in system for capturing energy from heat expelled in exhaust of engine of vehicle and storing captured energy.    DESCRIPTION OF DRAWING(S) - The drawing shows the block diagram for thermal auxiliary power unit.    System for capturing energy (100)    Generator (104)    Condenser (108)    Evaporator (114)    Absorber (116)