But just because of the bigger surface area of the radiator. A conventional compressor with the same surface area of its radiator as the peltier system will per

But just because of the bigger surface area of the radiator. A conventional compressor with the same surface area of its radiator as the peltier system will perform the same (provided they are at the same temperature). This is why heatsinks on CPUs have fins: to increase the surface area where the heatsink is in contact with the (hopefully cooler) surrounding air. The windings of a radiator are very much the same idea.