A SYSTEM-LEVEL FRAMEWORK FOR COUPLED THERMAL–ELECTRICAL OPTIMIZATION OF THERMOELECTRIC GENERATORS FOR LOW-GRADE WASTE HEAT RECOVERY
Keywords:
thermoelectric generator; low-grade waste heat; Seebeck effect; thermal resistance; load matching; net power; experimental methodologyAbstract
Thermoelectric generators (TEGs) offer a solid-state route for recovering part of the energy contained in low-grade waste heat. Their practical performance, however, is determined not only by the intrinsic properties of the thermoelectric material, but also by thermal contacts, heat-exchanger design, the temperature difference established across the module, electrical-load matching, and the power consumed by auxiliary equipment. This paper develops a system-level analytical framework for evaluating these coupled factors. The framework combines the Seebeck voltage relation, a lumped thermal-resistance network, a Thevenin-equivalent electrical model, and net-power accounting. A normalized load-matching curve is derived analytically to illustrate the maximum-power condition under fixed operating parameters. In addition, a measurement protocol is proposed for repeatable laboratory assessment of a TEG prototype, including sensor placement, load sweeps, repeated trials, uncertainty reporting, and comparisons between baseline and modified configurations. The figures and analytical curve in this paper are conceptual or model-derived; they are not experimental measurements. The main contribution is a practical workflow that helps distinguish material-level potential from system-level performance and prevents gross electrical output from being confused with net recovered power. Experimental validation with a specified TEG module and measured heat input is required before device-specific performance claims can be made
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