Simple tool to evaluate the impact of daylight on building energy consumption

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

This paper presents a simple building simulation tool for integrated daylight and thermal analysis. The tool is capable of importing the thermal and visual properties for different glazings and shading positions from the Window Information System (WIS) program. A coupled ray-tracing and radiosity methodology is used to derive the daylight levels for different sky conditions. Both detailed daylight distribution for a particular day and time and hourly discrete values on a yearly basis may be obtained. For an integrated simulation the hourly daylight levels are fed into an existing simple thermal simulation program capable of calculating energy demand and the indoor environment. Straightforward control systems for general and task lighting systems have been implemented together with a shading control strategy that adjusts the shading according to the indoor operative temperature, the risk of glare and the profile angle of the sun. The implemented daylight calculation method allows for shades from the window recess and overhang, and for distant shades blocking the sky vault. Comparisons with the ray-tracing program Radiance show that the accuracy of this approach is adequate for predicting the energy implications of photoresponsive lighting control. The amount of input is small, which makes the tool useful for integrated daylight optimisation in the early design process.
Original languageEnglish
JournalSolar Energy
Volume82
Issue number9
Pages (from-to)787-798
ISSN0038-092X
DOIs
Publication statusPublished - 2008

Fingerprint Dive into the research topics of 'Simple tool to evaluate the impact of daylight on building energy consumption'. Together they form a unique fingerprint.

Cite this