Environmental and Thermoeconomic Study of the Impact of Using Air-Cooled Condensers in the Kalina Cycle for Power Generation in Hot and Dry Regions

The Kalina cycle utilizes low-temperature heat sources to generate high-pressure vapor for running a turbine to produce power. Since the vapor at the turbine exit is relatively low temperature, a cool medium is required to liquefy the vapor at the condenser. This requirement imposes a practical limitation to the Kalina cycle for application in hot and dry regions. This paper studies the environmental and economic impact of using air-cooled condensers in the Kalina cycle. A dual Kalina cycle (KSC-D), the hybrid dual Kalina cycle (KSC-Dh), and the basic Kalina cycle (KSC-1) have been compared, considering Tarasht Steam Power Plant, as a case study. Subsequently, power output, water consumption, CO2 emission, and IRR , NPV were investigated for each case. Results show the least power output (4346704 kWh year-1) and the maximum power output (5008627 kWh year-1) belong to the basic Kalina cycle with an air-cooled condenser (KSC-1a) and the KSC-Dh cycle, respectively. Moreover, using air-cooled condensers in the dual Kalina cycle (KSC-Da) saves about 425825×103 m3 of water annually. KSC-Da is the most cost-effective and has the shortest payback time of three years. Also, for KSC-Da, the natural gas saved is 0.7765 to 1.22 Mm3 year-1, and the reduction in CO2 emission is about 4378 Tons year-1. The overall results indicate that although the KSC-Da ranks fourth in terms of power output among the different cases (producing 4564262 kWh year-1), it is still the most viable choice regarding the impact on the environment and reducing the amount of CO2 emissions.