Design of energy recovery systems: thermoelectric combi boiler generator and power analysis

Gas-fired combi boilers are commonly used to meet the need for heating and general-purpose hot water indeveloping countries. In this study, a thermoelectric combi boiler generator (TECBG) was developed. When the boileris operated, cold water flows through the cold surface of TECBG and enters the boiler. In the same way, it is used byflows through the hot surface of TECBG in heated water. Thus, temperature difference occurrs between the surfacesof TECBG. The temperature difference is converted into electrical energy by Seebeck effect. The proposed system wasimplemented on a domestic combi boiler. The maximum temperature difference between the designed system and theTECBG surfaces was recorded as 48 ◦ C. 12V9AH battery was used to charge through a DC-DC charge regulator. About14.28 Wh power was generated by the TECBG when the temperature difference of the TECBG, current, and voltagewere 48 ◦ C, 1.18 A, and 13.8 V, respectively. The electrical energy consumed by the combi boiler was measured as115 Wh. Although the obtained energy is not quite high, it is an important gain in terms of energy efficiency becauseaccording to data recorded in Turkey, there are 15 million combi boiler users. Assuming that a single heating boilerruns for 4 h, it is possible to produce 306.6 GWh/year, derived from 14.28 Wh × 4 h × 365 days × 15,000,000 heatingboiler. The proposed system provides significant advantages and thus can decrease power consumption.

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[1] Lin HP, Yeh LT, Chien SC. Renewable energy distribution and economic growth in the US. International Journal of Green Energy 2013; 10 (7): 754-62.
[2] Ahıska R, Mamur H. Development and application of a new power analysis system for testing of geothermal thermoelectric generators. The International Journal of Green Energy 2016; 13 (7): 672-681. doi: 10.1080/15435075.2015.1017102
[3] Dai D, Zhou Y, Liu J. Liquid metal based thermoelectric generation system for waste heat recovery. Renewable Energy 2011; 36 (12): 3530-3636.
[4] Zhang Y, Wang X, Cleary M, Schoensee L, Kempf N et al. High-performance nano-structured thermoelectric generators for micro combined heat and power system. Appl. Thermal Engineering 2016; 96: 83-87. doi: 10.1016/j.applthermaleng.2015.11.064
[5] Shi Y, Wang Y, Deng Y, Gao H, Lin Z et al. A novel self-powered wireless temperature sensor based on thermoelectric generators. Energy Conversion and Management 2014; 80: 110-116. doi: 10.1016/j.enconman.2014.01.010
[6] Suter C, Jovanovic ZR, Steinfeld A. A 1 kW thermoelectric stack for geothermal power generation-Modelling and geometrical optimization. Applied Energy 2012; 99: 379-385. doi: 10.1016/j.apenergy.2012.05.033
[7] Sornek K, Filipowicz M, Rzepka K. The development of a thermoelectric power generator dedicated to stovefireplaces with heat accumulation systems. Energy Conversion and Management 2016; 125: 185-193. doi: 10.1016/j.enconman.2016.05.091
[8] Jang j, Tsai Y, Wu C. A study of 3-D numerical simulation and comparison with experimental results on turbulent flow of venting flue gas using thermoelectric generator modules and plate fin heat sink. Energy 2013; 53: 270-281.
[9] Özkaymak M, Baş Ş, Acar B, Yavuz C, Boran K et al. Atık baca gazı kullanımı ile termoelektrik jeneratörlerde elektrik üretiminin faydalı kullanımının incelenmesi. Gazi Üniversitesi Fen Bilimleri Dergisi 2014; 2 (4): 289-298 (in Turkish with an abstract in English).
[10] Brazdil M, Rospilis J. Thermoelectric power generation utilizing the waste heat from a biomass boiler. Journal of Electronic Materials 2013; 42 (7): 2198-2202.
[11] Montecucco A, Siviter J, Knox AR. Combined heat and power system for stoves with thermoelectric generators. Applied Energy 2017; 185: 1336-1342.
[12] Atmaca AU, Erek A, Altay HM. Comparison of two numerical approaches to the domestic hot water circuit in a combi boiler appliance. Energy and Buildings 2016; 127: 1043-1056. doi: 10.1016/j.enbuild.2016.06.053
[13] Başkaya S, Karaaslan S, Çalışır T, Yılmazoğlu MZ, Yılmaz TO. Experimental and numerical study on thermoelectric generator performance applied to a condensing combi boiler. Heat Transfer Engineering 2015; 36 (14-15): 1292-1302.
[14] Qui K, Hayden ACS. Development of a thermoelectric self-powered residential heating system. Journal of Power Sources 2008; 180: 884-889.
[15] Alptekin M, Çalışır T, Başkaya S. Design and experimental investigation of a thermoelectric self-powered heating system. Energy Conversion and Management 2017; 146: 244-252. doi: 10.1016/j.enconman.2017.05.033
[16] Rowe DM. Thermoelectric waste heat recovery as a renewable energy source. International Journal of Innovations in Energy Systems and Power. 2006; 1 (1): 13-23.
[17] Ahıska R, Mamur H, Uliş M. Modelling and experimental study of thermoelectric module as generator. Journal of the Faculty of Engineering and Architecture of Gazi University 2011; 26 (4): 889-896 (article in Turkish with an English abstract).
[18] Bierschenk J. Optimized thermoelectric for energy harvesting applications. In: IEEE 2008 International Symposium on the Applications of Ferroelectrics ISAF; Santa Re, USA; 2008. pp. 1-4. doi: 10.1109/ISAF.2008.4693950
[19] Dalola S, Ferrari M, Ferrari V, Guizzetti M, Marioli D et al. Characterization of thermoelectric modules for powering autonomous sensors. IEEE Transaction on Instrumentation and Measurement 2009; 58 (1): 99-107. doi: 10.1109/TIM.2008.928405