I. Introduction
Thermoelectric energy harvesting is interesting due to the omnipresence and continuous operation that is time independent. The output voltage of thermoelectric generator (TEG) is in proportion to the temperature difference between its two junctions. Typically TEG is modelled as ideal voltage source with fixed source resistance . State-of-the-art thin-film TEG [1] has much smaller area size than conventional TEGs [2] [3]. Besides being compact, thin-film TEG also allows higher power to be generated per device area, which enables further miniaturization of the entire system size. Despite the newer TEG has higher output voltage than conventional TEGs, the internal resistance is higher (400 ohms vs. less than 10 ohms) and smaller output current as trade-offs. Performances of different TEGs are summarized in Table I. Comparisons of different TEGs at
TEG type | Device Area | Power/Area | |||
---|---|---|---|---|---|
Micropelt MPG-D751 [1] | 1.68V | 3.74mA | 1.42mW | 42mm × 3.3mm | |
Tellurex G2–30-0313 [2] | 0.22V | 29mA | 1.58mW | 30mm × 30mm | |
Marlow Technology TG12–2.5 [3] | 0.55V | 83mA | 11.4mW | 30mm × 30mm |