I made four heat sinks from aluminium L-profile for the linear TEC drive. Two 30 mm long for each side of the H-bridge (middle), and two 50 mm long for the voltage regulators(top right).
The regulators take 5 V input and produce 2 V, so they each dissipate 3V *ITEC Watts. The H-bridge dissipation is load-dependent, but for a low resistance load the dissipation is almost 2V*ITEC Watts. Here I am using a resistor (lower left) as a dummy load.
I tested the drive at 1 A for a few minutes, and the heat sinks do get quite warm. For continuous use at 2 A I think a fan will be required.