Evaluation of the Effectiveness of Ceiling Fans for Reducing Heating Requirements in Army Facilities

摘要

Many claims have been made for ceiling fans as energy saving devices. Fans destratify the air in a building; that is, they reduce the temperature differences between floor and ceiling. Depending on outside conditions, this can reduce heat loss. To quantify the effectiveness of fans during the heating season, USA-CERL, funded through a Facilities Engineering Applications Program (formerly FTAT) project, collected vertical thermal stratification measurements in Army buildings that had been equipped with ceiling fans. The buildings were located at Fort Carson, CO and Fort McClellan, AL. By analyzing how much the key building temperatures (ceiling, floor, and mean indoor) changed when ceiling fans were used, the USA-CERL engineers estimated the energy savings associated with fans. The results showed that, in general, the buildings with the greatest initial stratification showed the greatest savings. In addition, the degree of thermal stratification was determined to be a linear function of outside air temperature. However, more research is needed to determine the relationship between stratification and building characteristics. Thus, the degree of stratification in a building and possible factors affecting it should be evaluated carefully before installing ceiling fans. (fr)