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The Active Thermal Tiles (ATTs) experiment explores another option for managing electronic component temperatures onboard spacecraft. The ATTs are based on thermoelectric devices that can alter the thermal gradient between the bus and component. Because ATTs do not rely on fluids or moving parts, they are highly reliable devices which make them attractive for use in spacecraft. An ATT experimental ground unit was tested in a vacuum chamber under 88 different conditions over a temperature range of 280K to 310K. The power supplied to the electronic component was varied between 5W and 40W, and the current running through the ATTs was varied between 0.0A and 3.0A. Conductance and the coefficient of performance were measured, and a performance map was created. In addition, the power used by the ATTs was compared against the power used by survival heaters. Results showed the ATTs require less power to create the same temperature differential as survival heaters proving ATTs are more efficient than a traditional survival heat approach. Also, a computer simulation of the ATT was calibrated and used to compare the two control methods for the ATTs: PID or On-Off. PID control was up to two times as efficient as On-Off control. Ground tests were run to confirm the results from the simulation.