The inventive method includes the utilization of different phase change materials with different melting temperature ranges in each of the headliner (3), the seats (7), and the instrument panel (12) of an automobile in order to save energy while improving thermal comfort for the passengers. When used in the seats (7), the phase change material can be included in the seat heater system. Preferable phase change materials are alkyl hydrocarbons and mixtures thereof, salt-hydrates, metals, alloys, poly-alcohols, and eutectics with phase changes within the desired temperature ranges and with appropriate heat storage capacities. Preferably, the phase change materials are directly incorporated in a polymeric compound structure, in an elastomeric compound structure, or in a foam structure in order to enhance the overall thermal capacity. When used in the seats (7), the phase change material incorporated in a polymeric or elastomeric structure is formed into a mesh-like material (9) and attached to a knitted spacer fabric (6).