Paper Conference

Proceedings of SimBuild Conference 2010: 4th conference of IBPSA-USA

     

Comparison of Building Load Performance Between First Principle Based Shading Algorithm and Implementable Shading Control Algorithm

Rui Zhang, Khee Poh Lam
Center for Building Performance and Diagnostics, Carnegie Mellon University Pittsburgh, PA 15213, USA

Abstract: This paper presents the findings on the impact of two window shading control strategies on office building thermal and lighting loads over a year's period through energy simulation in four different climatic contexts in the United States. While it is well known that window shades affect heat gain and loss through windows and thus building energy loads, there is limited information on the actual magnitude and specific behavior of their effects on the building thermal and lighting loads. The objective of the described study is to generalize the magnitude of the impact from window shading control strategies on building thermal and lighting loads over a year by modeling a representative office building construction in indicative geographical locations as well as internal window shades representative of those that are commonly used. Two control algorithms are developed and evaluated which are the ideal algorithm and implementable. The basic principle of both of the algorithm is to maximize heat gain and minimize heat loss when the building is in heating condition, and performs the opposite when the building is in cooling condition, subject to glare control. The ideal algorithm is an optimized algorithm, however, some of the information that is used in the ideal algorithm is not available for a “real world” controller. Therefore, a simplified implementable shading control algorithm is also described, which will take sensor measurable outdoor and indoor conditions as input, including outdoor dry bulb temperature and transmitted solar radiation. EnergyPlus (Version 3.1) is used to conduct the yearly thermal and lighting loads computation. The control algorithm is implemented through the BCVTB (Building Control Virtual Test Bed). BCVTB is a software environment that allows expert users to couple different simulation programs for distributed simulation or for a real-time simulation that is connected to a building control system.
Pages: 394 - 401
Paper:
simbuild2010_TS07B-03-Zhang