Experimental Evaluation of HVAC Energy Conservation Options for ModularClassrooms

摘要

Three modular classrooms at one school campus and twornmodular classrooms at a second campus were monitoredrnto measure the effectiveness of the heating ventilating andrnair conditioning systems and to compare the energyrnsavings made possible by several types of HVAC systemrndesign improvements. All of the classrooms are similar inrnconstruction and all are located in similar environmentsrnnear Raleigh, NC. One classroom at each campus has arnwater source heat pump designed specifically for mobilernbuildings. The water exchanges heat with the earth andrnthe atmosphere through a PVC heat exchanger that lies onrntop of the ground in the crawl space.rnThe three classrooms at the first campus are occupiedrnthroughout the summer. One heat pump is standard, butrnone water source heat pump and one air source heat pumprnare equipped with exhaust air-to-inlet air heat exchangersrnthat recover energy in the ventilation air. The secondrncampus is closed in the summer. There the thermostats arernprogrammed for weekend and nighttime set back, butrnthere is no ventilation energy recovery.rnData loggers recorded the temperatures of the indoor airrnand outdoor air at one-minute intervals throughout thernyear. Switches were installed on the doors to record therntimes that they were open, and indoor COrnCO2 levels werernrecorded at one-minute intervals for typical days in eachrnseason. The capacity, load, and COP of each heat pumprnwere established approximately at various conditions byrnmeasuring the electrical power requirement, the ductrnairflow rate, the air temperatures, and the indoor andrnoutdoor humidity. The refrigerant suction and dischargernpressures were measured periodically throughout the testrnperiod.