Experimental investigation of waste heat recovery potential from car radiator with thermoelectric generator

Abstract

Thermoelectricity (TE) is a zero-emission and low-energy generation solution based on semi-conductor’s technology. Thermoelectric modules (TEM) consists of p-doped and n-doped materials connected by copper junctions, and covered by ceramic wafer. It can be used for cooling purposes (TEC) by converting electricity into heat, or in generator mode (TEG) converting thermal energy into electricity. In general cases it uses thermal waste from existing systems to generate complementary power under Seebeck effect. This experimental work investigates the opportunity to produce electricity from recovering automobile radiator waste heat. A Mathematical model is firstly used to predict thermoelectric generator performances under different conditions. However, the direct potential is then explored from direct contact applied on a RENAULT Kangoo 1.5 DCI passenger car radiator within a single TEM. Then, a Test bench is setup under improved laboratory conditions, using adapted heat exchangers. Besides, an Arduino micro controller is envisaged wherein temperatures, flows and electrical data are depicted in real time and stored to the lab computer. Results showed considerable performance of TEG for radiator and Test Bench scenarios, with a great fit of the developed mathematical model. Likewise, it is found that test Bench conditions have improved experimental results, the divergence is not bigger than 6% from the T-model. In general, the optimal predicted point by theoretical T-Model is for (RL = 0.25 Ohm, I = 1 A, V = 1.4 V) and in consequence (P = 1.4 W), with an efficiency of 2.8%. The maximum power obtained is (P = 1.8 W), with an efficiency of 3.85% which is considered an optimistic value in real conditions.