Study On Waste Heat Generation Performance Of Thermophotovoltaic Using Rare Earth Emitter

As a novel way to generate power, Thermophotovoltaic (TPV) utilizes the high-temperature exhaust gas produced in manufacture processes of steel and glass. This paper analyzes and researches TPV system used for waste heat recovery.On the basis of fundamental and specific environment, we choose rare-earth emitter, TCOs filter and Si photovoltaic cell as the main components of TPV system. In accordance with radiation transfer equation and energy balance equation, we introduce the typical spectral analysis to determine the optimized selective coating thickness of rare-earth emitter. Results indicate that Yb2O3 is the suitable material for coating due to its selective radiation characteristic. The optimized thickness has a linear relationship with the temperature of emitter. Working temperature of TPV system applied to recover waste heat of exhaust gas from glass kiln ranges between 1000-1800 K at which the optimized thickness L of Yb2O3 is 0.20-0.23 mm. Under this condition, the maximum of output power and generating efficiency could be achieved.Then we analyze the emission spectral of rare-earth emitter filtering performance of TCOs filter as well as generating characteristics of Si cell, and use Monte Carlo Method to study the generating performance of total system. Results show that TPV system with Yb2O3 coated on the SiC substrate has a significant improve in efficiency. Meanwhile, TCOs filter makes the similar effect and still has a huge potential for efficiency improvement. This system has a generating power of 1.4 kW/m2, as well as an efficiency of 16.6% at temperature T of 1600 K. TPV used for generating is proved to be feasible in the experiment, which converts heat into radiation energy, and electrical energy finally.Lastly, we analyze the economy and industrial application of TPV system used for waste heat recovery. When the investment is around 14500ï¿¥/kW, the cost for generating is 0.21ï¿¥/kw.h. Combining cooling system of Si cell and preheating system of glass kiln makes the total energy utilization efficiency up to 66%. TPV makes a remarkable effect in energy saving and has a bright application prospect.