Modeling and characteristics analysis of hybrid cooling-tower-solar-chimney system

• A 3-D model for hybrid cooling-tower-solar-chimney system is developed.
• The inclusion of heat exchangers into solar chimney boosts the power output.
• The huge jump in power output is at the expense of heat dissipation capacity.
• The heat exchanger as second heat source has greater impact on system performance.

The hybrid cooling-tower-solar-chimney system (HCTSC), combining solar chimney with natural draft dry cooling tower, generates electricity and dissipates waste heat for the coupled geothermal power plant simultaneously. Based on a developed 3-D model, performance comparisons between the HCTSC system, solar chimney and natural draft dry cooling tower were performed in terms of power output of turbine and heat dissipation capacity. Results show that compared to the traditional solar chimney with similar geometric dimensions, HCTSC system can achieve over 20 times increase in the power output of turbine. However, this huge jump in power output is at the expense of heat dissipation capacity, which may lead to the malfunction of the coupled thermal power plant. By increasing the heat transfer area of the heat exchanger, the HCTSC system can manage to recover its heat dissipation capacity.