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This article starts by introducing the ongoing South Africa electricity crisis followed by thermoelectricity, in which eighteen miscellaneous applicable case studies are structurally analysed in detail. The aim is to establish best practices for the R&D of an efficient thermoelectric (TE) and fuel cell (FC) CCHP system. The examined literature reviews covered studies that focused on the thermoelectricity principle, highlighting TE devices’ basic constructions, TEGs and TECs as well as investigations on the applications of thermoelectricity with FCs, whereby thermoelectricity was applied to recover waste heat from FCs to boost the power generation capability by ~7–10%. Furthermore, nonstationary TEGs whose generated power can be increased by pulsing the DC-DC power converter showed that an output power efficiency of 8.4% is achievable and that thicker TEGs with good area coverage can efficiently harvest waste heat energy in dynamic applications. TEG and TEC exhibit duality and the higher the TEG temperature difference, the more the generated power—which can be stabilised using the MPPT technique with a 1.1% tracking error. A comparison study of TEG and solar energy demonstrated that TEG generates more power compared to solar cells of the same size, though more expensively. TEG output power and efficiency in a thermal environment can be maximised simultaneously if its heat flux is stable but not the case if its temperature difference is stable. The review concluded with a TEC LT-PEM-FC hybrid CCHP system capable of generating 2.79 kW of electricity, 3.04 kW of heat, and 26.8 W of cooling with a total efficiency of ~77% and fuel saving of 43.25%. The presented research is the contribution brought forward, as it heuristically highlights miscellaneous thermoelectricity studies/parameters of interests in a single manuscript, which further established that practical applications of thermoelectricity are possible and can be innovatively applied together with FC for efficient CCHP applications.

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Sustainable energy is gradually becoming the norm today due to greenhouse warming effects; as a result, the quests for different renewable energy sources such as photovoltaic cells as well as energy efficient electrical appliances are becoming popular. Therefore, this article explores the alternative energy case for thermoelectricity with focus on the steadystate mathematics, mixed modelings and simulations of multiple TEGs and TECs modules to study their performance dynamics and to establish their optimal operation points using Matlab and Simulink. The research substantiates that the output current from TEGs or input current to TECs, initially respectively increases the output power of TEGs and the cooling power of TECs, until the current reaches a certain maximum optimal point, after which any further increase in the current, decreases the TEGs' and or TECs' respective output and cooling powers as well as efficiencies, due to Ohmic heating and or entropy change caused by the increasing current. The research main contributions are elaborate easy to understand TEGs/TECs theoretical formulations as well as static and dynamic simulated models in Matlab/Simulink, that can be used initially to dynamically investigate an infinite quantity of TEG and TEC modules connections, be it in series and or in parallel. This is to assist system designers grasp TEGs and TECs theoretical operations better and their limits, when designing energy efficient waste heat recovery (using TEGs)/cooling (using TECs) systems for industrial, residential, commercial and vehicular applications.

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