Developing Integrated Envelope and Lighting Systems for Commercial Buildings

Integrated envelope and lighting systems achieve significant energy, peak demand, and cost savings over typical component-by-component design practice by leveraging the interactive energy balance between electric lighting energy use and cooling due to lighting and solar radiation. We discuss how these savings can be achieved using conventional glazing and lighting components by taking an integrated systems design approach. We describe integrated dynamic envelope and lighting systems, currently under development, that actively achieve this energy balance through the use of intelligent control systems. We show how prototypical daylighting systems can be used to increase the efficacy and distribution of daylight throughout the space for the same or less glazing area as a typical window, while achieving greater energy savings with increased visual comfort. Energy performance simulations and field tests conducted to date illustrate significant energy savings, peak demand reductions, and potential practical implementation of these proposed systems.