Effect of Wind on the Performance of Air‐Cooled Condensers - Final Project Report

Cover of report

Effect of Wind on the Performance of Air‐Cooled Condensers - Final Project Report - Final Project Report. (PDF file, 143 pages, 6.2 megabytes).


Publication Number: CEC-500-2013-065
Report Date: June 2010



Given the increasing demands for California’s limited freshwater supplies, power plants that use air-cooled condensers, commonly referred to as dry cooling, are increasingly being used. As opposed to conventional cooling towers, air-cooled condensers use ambient air to cool and condense steam and therefore use no water. The performance of the air-cooled condenser is therefore susceptible to ambient wind and temperature conditions.

This study investigated the effects wind speed and direction has on the performance of a full-sized air-cooled condenser at an operating power plant through field testing and monitoring and computational fluid dynamics modeling.

Air-cooled condenser performance was affected both by hot air recirculation and by fan performance degradation. The combined effect of the two mechanisms increased with wind speed up to an increase in turbine exhaust pressure of as much as two inches of mercury (a unit of measure for pressure) at wind speeds over 20 miles per hour (mph) and ambient temperatures above 100 F.

The highest recirculation occurred at intermediate wind speeds between about 7.5 and 15 mph. Above 15 mph, the recirculation diminished and then increased slowly up to the maximum wind speeds of 30 to 35 mph. At the higher temperatures and wind speeds, the effect of air flow reduction was two to three times that of recirculation.

The agreement between the field data and the computational fluid dynamic modeling results was generally satisfactory, with the notable exception that the modeling results did not predict the increase in recirculation in the moderate speed range. This difference is currently unresolved. Steps to address wind effects and enhance air-cooled condenser performance are modeled and evaluated.