The design of the so-called "Peltier modulator" is presented. It is a new dual-stage consumable-free thermal modulator for TA-GC-MS. It requires only electrical power for operation as it facilitates thermo-electric coolers instead of cryogenics for trapping and resistive on-column heating for re-injection. Trapping and desorption temperatures, as well as modulation cycles are freely adjustable. The stationary phase for the trapping region can be selected to suit the specific application, since common fused silica capillary is used. The Peltier modulator's performance is demonstrated with a broad range of different standard substances and with heavy crude oil as a complex real life sample. Successful modulation from n-pentane to pyrene (boiling points = 36/394 °C) is presented. The produced peaks show the narrowest bandwidths ever reported for a consumable-free thermal modulator, i.e. 12.8±1.2 ms for n-pentadecane. The Peltier modulator is rugged, cost effective, requires low maintenance and decreases security issues significantly, compared to commercial available solutions using liquid N2/CO2.