The Artificial Sky Laboratory At Oklahoma State University

Utilization of daylight is one of the most cost-effective energy-efficient strategies to design and engineer low-energy buildings. Integration between daylighting and electric lighting systems in commercial buildings results in a significant reduction in annual energy use and operating cost. As in other engineered systems, quantification of the performance of daylighting systems should dictate their design. In the US however, the majority of students of architectural engineering and architecture; architectural engineers; and architects currently use inaccurate rules of thumb and/or over-simplified methods to design and predict performance of daylighting systems. The Architectural Engineering Program at OSU is in the process of adopting and implementing the approach of testing daylighting scale models, which has proven to be able to accurately predict and quantify the performance of daylighting systems. With the support of the National Science Foundation (NSF), the school is currently in the process of building a cutting-edge daylighting laboratory, i.e., the Artificial Sky Dome. The new laboratory will help integrate the engineering of daylighting systems into the school’s curriculum, with the anticipation that this will nurture the scientific background and design skills of undergraduate students. The secondary mission of the laboratory is to disseminate the same knowledge and/or skills between graduate students, faculty, and practicing professionals. The laboratory will also be an effective venue to integrate teaching and research. The specific outcome expected from this project is to enable OSU’ students, and consequently OSU’ graduates to effectively incorporate daylighting systems into the design of buildings, which should result in the conservation of energy used to operate buildings, and the mitigation of related negative environmental impacts. The paper reports on the need of daylighting laboratories and their relevance to achieve a sustainable future through the design of low-energy buildings. The paper also reports on the existing tools currently being used in the USA to test daylighting scale models. The design challenges of building the new laboratory that assures accurate testing and results will be discussed. 1. Scope of Interest Integration of daylight into buildings saves energy directly and indirectly. As published by the Energy Information Administration [1], an average of 44% of the electricity consumption in office buildings in the US is consumed by artificial lighting systems. Furthermore, thermal load from electric lighting systems appears as a component of the internal thermal loads in P ge 9.232.1 “Proceedings of the 2004 American Society for Engineering Education Annual Conference & Exposition Copyright © 2004, American Society for Engineering Education” conditioned spaces, which contributes to higher cooling loads and consequently higher cost of air conditioning. That is why minimal use of electric light is considered a fundamental strategy to minimize the use of purchased energy in commercial buildings. Utilization of natural light in lieu of or integrated with electric light in commercial and institutional buildings should result in a significant reduction of energy use and operating cost. Accurate evaluation of the performance of daylighting systems promotes improved design and allows the potential energy savings to take place while designing new buildings or retrofitting existing buildings. Optimum design of daylighting systems admits only the minimal amount of needed daylight without an “overdesign” of the system that may admit much more daylight than needed, which may cause visual discomfort and/or unnecessary high solar heat gain in perimeter spaces.