Using waste heat of high capacity wind turbines in a novel combined heating, cooling, and power system

摘要

In this paper, a new combined cooling, heating and power system was proposed to investigate the utilization of the waste heat of 12 high capacity wind turbines, each has a capacity of 7500 kW. This system includes a modified organic Rankine cycle consisting of a regenerator and feedwater heater, an absorption refrigeration cycle, and heat exchangers. It is investigated theoretically to assess power, cooling, and hot water production. There is a large number of wind data during a year in the location of these high capacity wind turbines (Noordoostpolder; Netherlands); therefore, to follow a logical procedure for each month and reduce calculations, the hourly average wind speed of 2 days of each season are selected. For the 15th day of the first and last months of each season, the hourly average wind speeds at 12 p.m. are considered. Energy analysis was performed for all chosen hourly average wind speeds; however, to reduce exergy calculations, the average wind speed of 12.25 m/s was selected. At this average wind speed, results indicated that the hourly produced net power, hot water at 65 degrees C, and cooling at -10 degrees C are 196.2 kWh, 35.5 m(3)/h, and 147.7 kWh, respectively. The highest exergy destruction rate belongs to the heat exchanger applied for recovering waste heat from high capacity wind turbine and equals to 74.82% of the total exergy destruction rate. The energy and exergy efficiencies of the proposed system were obtained as 45.32% and 38.61%, respectively. Finally, a simple economic analysis was carried out, accordingly, the payback period was calculated as 1.9 years and it resulted that the proposed system is cost-efficient. (C) 2020 Elsevier Ltd. All rights reserved.