Innovative portable electronic devices powered by thermoelectric generators from waste heat

Abstract

This research was aimed at thermoelectric generator’s (TEG’s) commercialization as a green power supply for portable consumer electronic devices (PCEDs) in the metropolitan market in Thailand. Technical assessment using four commercial 4 cm x 4 cm TE modules to transfer heat from temperature-controlled water yielded power outputs of 2.1-100.8 mW and voltages of 0.16-1.08V. A business research by a questionnaire with the sample size of 400 at 0.05 level of significance () and in-depth qualitative interview found 12 PCEDs and 11 heat / coldness sources with potential for product development. Portable power supply problems were also prioritized. Product qualification criteria with the most importance were deployed into technical requirements for product development techniques with QFD and TRIZ. A prototype comprised 8 components using 3 referred TE modules. It was evaluated for charging characteristics in 5 conditions of uses and produced the maximum power of 4.82 W, with the outstanding feature in the lowest starting temperature differential of 26C. Fully charging a 3,000 mAh Li-ion battery in comparison with other commercial products, in the same condition, the prototype finished charging process for about 15.8-25.4% faster in duration, with 30.3-41.4% higher maximum power, but with 5.7-13.2% lower maximum power per unit area. Commercialization and business plan was then conducted to focus on the target customers as travelers and government officers with long stay jungle trip. The additional target of people with inconvenience to access electrical power sources for PCEDs was also considered. The business was financially evaluated for satisfactory valuation, i.e. NPV= THB 19,965,919 , IRR= 274.77%, and with 1 year payback period