LED lighting design strategies to enhance window appearance and increase energy savings in daylit office spaces

Amirkhani, Mehdi, Garcia-Hansen, Veronica, & Isoardi, Gillian (2015) LED lighting design strategies to enhance window appearance and increase energy savings in daylit office spaces. In Davis, Wendy (Ed.) Proceedings of the Asia-Pacific Lighting Systems Workshop 2015, University of Western Sydney, Sydney, Australia, pp. 1-7.

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Vertical windows are the most common and simplest method to introduce daylight to interior spaces of office buildings, while also providing a view and connection to the outside. However, high contrast ratios between windows and surrounding surfaces can cause visual discomfort for occupants and can negatively influence their health and productivity. Consequently, building occupants may try to adapt their working environment through closing blinds and turning on lights in order to improve indoor visual comfort. Such interventions defeat the purpose of daylight harvesting systems and can increase the forecast electric lighting consumption in buildings that include such systems. A simple strategy to prevent these problematic consequences is to reduce the luminance contrasts presented by the window wall by increasing the luminance of areas surrounding the window through the sparing use of energy-efficient supplementary lighting, such light emitting diodes (LEDs). This paper presents the result of a pilot study in typical office in Brisbane, Australia that tests the effectiveness of a supplementary LED lighting system. The study shows an improvement in the appraisal of the visual environment is achieved using the supplementary system, along with up to 88% reductions in luminance contrast at the window wall. Also observed is a 36% reduction in the likelihood of user interventions that would increase energy usage. These results are used as the basis of an annual energy simulation of the test office and indicate that supplementary systems could be used to save energy beyond what is typically realised in side lit office spaces.

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ID Code: 87753
Item Type: Conference Paper
Refereed: Yes
Additional Information:

"The Asia-Pacific Lighting Systems Workshop is a two-hour event covering seven discussions involving several leading scientists in the Asia-Pacific region. The speakers will present on Lighting Measurements, Standards and Regulations, Lighting Controls and Innovative Applications to reduce Energy Consumption.

Highlights of the workshop include Ian Cowling, Adrian Cupitt, Amir Moayedzadeh and Rod Hewins discussing ‘Can you believe your light meter?’; and Dorukalp Durmus and Wendy Davis examining ‘Colour Difference and Energy Consumption of Absorption-minimising Spectral Power Distributions’."

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Keywords: Windows, lighting energy consumption, office room, LED (light emitting diode), blinds
ISBN: 978-0-9945422-0-5
Subjects: Australian and New Zealand Standard Research Classification > BUILT ENVIRONMENT AND DESIGN (120000) > ARCHITECTURE (120100) > Architectural Science and Technology (incl. Acoustics Lighting Structure and Ecologically Sustainable Design) (120104)
Divisions: Current > Schools > School of Chemistry, Physics & Mechanical Engineering
Current > Schools > School of Design
Current > QUT Faculties and Divisions > Creative Industries Faculty
Past > QUT Faculties & Divisions > Faculty of Science and Technology
Past > Institutes > Institute for Creative Industries and Innovation
Copyright Owner: Copyright 2015 Asia-Pacific Lighting Systems Workshop
Deposited On: 24 Sep 2015 22:26
Last Modified: 04 Nov 2016 03:18

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