Keywords |
Smart window system ; Control variable ; HVAC system ; Building energy performance |
Abstract |
It has been interested in appling smart window system to buildings in order to control solar transmittance by active way. The performance of control strategies on the smart window system, especially electrochormic window (ECW), have not fully evaluated in the perspective of building energy consumption. The presented article provides potential control parameters and logics to operate ECW. It also evaluates building energy performance by the developed ECW controls conducting annual building energy simulation for a medium size office building model. Five control parameters are derived from time scheduling (SPC), solar irradiance (IRD), outdoor air temperature (OAT), cooling demand (CMD), and room air temperature(RAT). Each control parameter has ranges or target values to activate ECW operation. The result shows the control methods can avoid solar transmittance by 90% thorough South, East, and West in the highest solar radiation day in Inchoen, Korea. ECW operation can reduce cooling equipment sizing by 20% in approximation and save annual HVAC energy consumption ranges from 11.22% to 20.70% by the control methods. The RAT would be the most effective control parameter from this study because it outperforms other parameters on annual HVAC energy saving and investment of system installation. |