1. DOPED SILICATE GLASS AND THERMOELECTRIC CONVERTERS MADE FROM IT Institute of Power Engineering and Automation of the Academy of Sciences of Republic of Uzbekistan

2. Thermoelectric Energy Converters made from Doped Silicate Glass The basic obstacle for wide application of thermoelectric converters made from chalcogenides of bismuth, antimony and lead (commercially accessible materials) is the high price (> $12000/kW) The raw materials for chalcogenides of bismuth, antimony and lead have rather limited resources, expensive and poisonous (Te, especially Tl) Technology of offered materials and structures with ZT > 1 is complex and results are badly reproduced The doped silicate glass is cheap (≈ $1500/kW), raw materials accessible and harmless, ZT ≈ 1 Main criterion of thermoelectric materials efficiency is dimensionless thermoelectric figure of merit ZT = S 2 Tσ/κ, here S is thermopower coefficient (V/K), T is temperature (K), σ and κ are electrical and thermal conductivity (Sm/m and W/m K accordingly) Этапы развития термоэлектрических материалов Application of thermoelectric converters is economically justified at ZT > 2 Commercially available materials have ZT < 1. J. W. Fairbanks, 2006

3. Structure of the thermoelectric energy supply Efficiency ZT and cost of TEC depend on the used thermoelectric material only Thermoelectric solar stations can be with or without concentrators of sunlight Concentrator adds $500 – 1000/кВт on the cost of TEC Sun light (heat) Service TEC Inverter Accumulator Electricity ~220 V, 50(60) Hz - 12(24) V D. M. Rowe, Thermoelectric Waste Heat Recovery as a Renewable Energy Source. I. J. Innovations in Energy Systems and Power 1 (2006), # 1 Термоэлектрический генератор Komatsu для дизелей 19.02.2009 http://www.equipnet.ru/news/tech/tech_15706.htmlhttp://www.equipnet.ru/news/tech/tech_15706.html J. Karni, SOLAR ENERGY: The thermoelectric Alternative. Nature Materials 10, July 2011 Kraemer, D. et al. High-performance flat-panel solar thermoelectric generators with high thermal concentration. Nature Materials 10, 532 (2011) B. I. Ismail, Thermoelectric Power Generation Using Waste-Heat Energy as an Alternative Green Technology. Recent Patents on Electrical Engineering 2009, 2, 27-39 27 V. R. Gandhewar, Fabrication of Solar Operated Heating and Cooling System Using Thermo-Electric Module. International Journal of Engineering Trends and Technology (IJETT) – 4 Issue 4 - April 2013 M. K. Rawat, A Review on Developments of Thermoelectric Refrigeration and Air Conditioning Systems: A Novel Potential Green Refrigeration and Air Conditioning Technology. International Journal of Emerging Technology and Advanced Engineering 3, Special Issue 3: ICERTSD 2013, Feb 2013, pages 362-367 Б. С. Поздняков, Е. А. Коптелов, Термоэлектрическая энергетика. М., Атомиздат, 1974, 264 с.

4. Raw materials and cost of doped silicate glass The doped silicate glass consists from the widespread, cheap and harmless substances – quartz sand, red lead, boric acid, oxides of aluminium, barium, magnesium, manganese, copper, iron. Dopant is ruthenium dioxide yet, but there is a possibility to replace it by oxides of nonprecious transition metals (iron, manganese, copper, …) which should be investigated further. It is required to investigate also ways of creation of the doped glass with n-type conductivity as well as effect of doping on thermal conductivity.

5. Possible applications of thermoelectric converters to waste energy recovery J. W. Fairbanks, 2006 Thermoelectric conversion of exhaust heat of automotive engine Thermoelectric converters can be used for energy harvesting at metallurgical works glass-melting furnace brick-making plant Solar energy plants

6. Possible applications of thermoelectric converters to waste energy recovery Thermoelectric power generation for Diesel-engine Cogeneration System (Komatsu Ltd., Japan) Combined Gas-turbine and thermoelectric aggregate (RF patent): 1 is the compressor, 2 is the free turbine (to drive the compressor), 3 is the combustor, 4 is the power turbine, 5 is the alternator, 6 is the calorifer, 7 are thermoelectric modules, 8 is the heat pump.

7. Automotive thermoelectric converter made from doped glass From Engine Into Atmo- sphere T H = 400 – 500 °С T C = 70 – 150 °С P el = 0,5 – 1 кВт The thermoelectric converter uses exhaust heat of car engine and replaces traditional electro mechanic alternator. It gives an fuel economy 2 to 10 %. Element of the thermoelectric generator Cooling air (or water)

8. State of art of doped silicate glass and developing of fabrications from it The physical mechanisms of electrical conductivity and thermopower generation in doped silicate glass as well as effect of glass and dopant structure, doping conditions on them are established now. The patent application on composition of the doped silicate glass as thermoelectric material is prepared Sketches of a design of the automobile thermoelectric generator and conditioner are developed Sketches of a design of thermoelectric generators of 100 and 300 W output from the doped glass for the household applications are developed. These generators work on liquid and firm fuel. Subsequent researches are necessary to create the doped silicate glasses with n-type conductivity that simplifies a design of the thermoelectric converter and improves efficiency of energy conversion