Abstract

*A Guide to Small-Scale Energy Harvesting Techniques*

semiconductor. Chemistry of Materials.

[57] Harikesh PC, Mulmudi HK, Ghosh B, et al. Rb as an alternative cation for templating inorganic lead-free perovskites for solution processed photovoltaics. Chemistry of Materials.

2015;**27**(16):5622-5632

2016;**28**(20):7496-7504

thermal stability up to 473 K. Journal

[49] Liao Y, Liu H, Zhou W, et al. Highly oriented low-dimensional tin halide perovskites with enhanced stability and photovoltaic performance. Journal of the American Chemical Society.

[50] Ke W, Stoumpos CC, Zhu M, et al. Enhanced photovoltaic performance and stability with a new type of hollow 3D perovskite {en}FASnI3. Science Advances. 2017;**3**(8):1701293

[51] Ke W, Stoumpos CC, Spanopoulos I, et al. Efficient lead-free solar cells based on hollow {en}MASnI3 perovskites. Journal of the American Chemical Society. 2017;**139**(41):14800-14806

[52] Krishnamoorthy T, Ding H, Yan C, et al. Lead-free germanium iodide perovskite materials for photovoltaic applications. Journal of Materials Chemistry A. 2015;**3**(47):23829-23832

Ge-based perovskites. RSC Advances.

[54] Lin Z-G, Tang L-C, Chou C-P. Characterization and properties of novel infrared nonlinear optical crystal CsGe(BrxCl1−x)3. Inorganic Chemistry.

[55] Zhang X, Wu G, Gu Z, et al. Active-layer evolution and efficiency improvement of (CH3NH3)3Bi2I9 based solar cell on TiO2-deposited ITO substrate. Nano Research.

[56] Saparov B, Hong F, Sun J-P, et al. Thin-film preparation and characterization of Cs3Sb2I9: A lead-free layered perovskite

[53] Lu X, Zhao Z, Li K, et al. First-principles insight into the photoelectronic properties of

2016;**6**(90):86976-86981

2008;**47**(7):2362-2367

2016;**9**(10):2921-2930

of Materials Chemistry A. 2016;**4**(43):17104-17110

2017;**139**(19):6693-6699

**12**

Thermoelectricity can be used to generate electrical power from temperature gradients or differences in naturally occurring geothermal heat and rocks, or from waste heat in man-made equipment and industrial processes. Thermoelectric energy harvesting systems are finding commercial applications to replace or recharge batteries in low power electronic systems. This chapter provides the fundamental thermoelectric theory related to power generation, including the theoretical analysis and numerical calculations required to calculate the thermoelectric efficiency and electrical power generated when a single thermoelectric couple, and a 127 couple thermoelectric module, are subject to different temperature gradients. A thermoelectric energy harvesting system, incorporating a low power boost converter and DC to DC converter, coupled with electrical energy storage in supercapacitors, is presented and enables a thermoelectric energy harvesting system to provide sufficient electrical power to operate low power electronic components and systems. The short-term challenge for thermoelectric energy harvesting is to become a cost effective and practical solution to replace batteries, and to be scaled to provide sufficient power to operate electrical rotating machines such as low power motors and pumps. The long-term challenge is to improve the efficiency, power output, and cost of thermoelectric modules and energy harvesting systems, and to develop from low power to low-to-medium power applications.

Keywords: thermoelectric, Seebeck, temperature difference, temperature gradient, thermal power generation
