As new thermoelectric modules emerge, there is a need for developing new or validating existing system level models that can be used in optimizing thermoelectric power generation systems. SEL has been developing a general system level model and experimentally validating the model. The model accommodates many system configurations, including but not limited to the number of modules, type of modules, geometrical parameters, and heat exchanger parameters. With this wide range of variables, it is possible to gain an understanding of the mechanisms of system performance and how they can be manipulated to optimize a thermoelectric system. The model is being validated by altering design parameters of a small prototype thermoelectric system being tested on SEL’s exhaust simulator test stand.