Faster and more accurate simulations of thermoelectric generators through the prediction of the optimum load resistance for maximum power and efficiency points

Abstract

There are two methods to predict the maximum power point (MPP) and the maximum efficiency point (MEP) of a thermoelectric generator: the Constant Temperature Difference method (CTD) and the Variable Temperature Difference method (VTD). These methods help engineers to determine the optimum load for MPP or MEP of thermoelectric generators, without the need of doing a load resistance scan (LRS), and are of particular interest to reduce the time needed to simulate large-scale thermoelectric systems.The objective of this work is to carry out an exhaustive comparative analysis between both methods to find out which one is the most accurate in predicting the load resistance for MPP (RLMPP) and MEP (RLMEP). Note that tuning values of load resistance lower or higher than these two optimum points can produce a significant loss of power or efficiency. Results demonstrate that, although CTD method has become widespread within the scientific community, VTD is the most accurate method. Additionally, the use of the VTD method allows the TEG model to generate more power and achieve higher efficiency. Finally, the time required to find MPP and MEP with CTD and VTD methods was more than 100 times less than using LRS method.