Advanced thermoelectric power system investigations for light-duty and heavy duty applications: Part I

The U.S. Department of Energy's National Renewable Energy Laboratory (NREL) has developed an integrated heat exchanger/thermoelectric power system analysis tool (in Matlab/Simulink environment) that simultaneously analyzes and optimizes the integrated effects of heat exchanger and thermoelectric power generator (TEPG) performance in light-duty-passenger (LDP) and heavy-duty (HD) vehicle waste heat recovery applications. Part I of this two-part paper describes the mathematical basis of this analysis approach as applied to TEPGs using single-material and segmented-leg thermoelectric (TE) couples. The integrated system analysis approach to heat exchanger / TEPG system performance allows NREL to simultaneously quantify the effects of important system design parameters, and heat exchanger and TEPG device design details on performance and power output in LDP and HD vehicles of interest. Part I discusses system power maximization, potential electrical power available, an cold side cooling mass flow requirements in LDP vehicle exhaust heat recovery applications. The model has been used in Part II of this technical paper to: (1) further investigate the behavior and interdependence of important thermal and TEPG system design parameters, and (2) predict potential TE system power output for a variety of thermal conditions in LDP and HD vehicles.