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Daylight metrics and energy savings

Mardaljevic, J., Heschong, L. and Lee, E. Daylight metrics and energy savings. Lighting Res. Technol. 41(3):261–283, 2009

Abstract: The drive towards sustainable, low-energy buildings has increased the need for simple, yet accurate methods to evaluate whether a 'daylit' building meets minimum standards for energy and human comfort performance. Current metrics do not account for the temporal and spatial aspects of daylight, nor of occupants comfort or interventions. This paper reviews the historical basis of current compliance methods for achieving daylit buildings, proposes a technical basis for development of better metrics, and provides two case study examples to stimulate dialogue on how metrics can be applied in a practical, real-world context.

	Author = {Mardaljevic, J and Heschong, L and Lee, E},
	Journal = {Lighting Research and Technology},
	Number = {3},
	Pages = {261--283},
	Title = {Daylight metrics and energy savings},
	Volume = {41},
	Year = {2009}}

Transmission illuminance proxy HDR imaging

Mardaljevic, J., Krausse, B. and Andersen, M. Transmission illuminance proxy HDR imaging: A new technique to quantify luminous flux. Lighting Res. Technol. Vol. 41, No. 1, pp. 27-49, 2009

Abstract: A technique to measure arbitrarily complex luminous fluxes across large areas is presented. The technique is founded on high-dynamic range (HDR) imaging technology and can be achieved using a standard consumer digital camera and everyday materials such as printer-grade white paper. The same approach can also be used to determine the direct and diffuse components of illuminance. The technique has been named transmission illuminance proxy - high dynamic range imaging or TIP-HDRI.

	Author = {Mardaljevic, J. and Painter, B. and Andersen, M.},
	Journal = {Lighting Research and Technology},
	Number = {1},
	Pages = {27--49},
	Title = {{Transmission illuminance proxy HDR imaging: A new technique to quantify luminous flux}},
	Volume = {41},
	Year = {2009}}

Sky model blends

Mardaljevic, J. Sky model blends for predicting internal illuminance: a comparison founded on the BRE-IDMP dataset. Journal of Building Performance Simulation, 1(3):163–173, 2008

Abstract: The BRE-IDMP validation dataset contains simultaneous measurements of sky luminance patterns and internal illuminances in two full-size office spaces. This benchmark dataset has been applied previously to test the illuminance predictions from a lighting simulation program under real sky conditions. Sky luminance patterns were mapped into the lighting simulation so that the absolute accuracy of the program could be evaluated without the uncertainties that are introduced when sky models are used. For this follow-on study, the BRE-IDMP dataset is now used to quantify the divergence between the sky model generated luminance patterns and the actually occurring conditions based on the resulting internal daylight illuminances. The internal illuminances were predicted using three 'narrow-range' models (CIE overcast, CIE clear and intermediate) and the Perez All-Weather model. Predictions from the narrow-range models were used to investigate formulations for sky model blends. The illuminance effect of arbitrary sky model blends is reproduced in a post-process of the illuminance predictions from the 'narrow-range' sky model types. The determination of an optimum sky model blend is described. The findings show that relatively simple blends of just two pure sky models (e.g. CIE overcast and intermediate) may be adequate for the prediction of time-varying illuminances founded on climatic test reference year data.

	Author = {Mardaljevic, J.},
	Journal = {Journal of Building Performance Simulation},
	Number = {3},
	Pages = {163--173},
	Title = {{Sky model blends for predicting internal illuminance: a comparison founded on the BRE-IDMP dataset}},
	Volume = {1},
	Year = {2008}}

Electrochromic vs PV

Mardaljevic, J. and Nabil, A. Electrochromic glazing and facade photovoltaic panels: a strategic assessment of the potential energy benefits, Lighting Res. Technol. Vol. 40, No. 1, pp. 55-76, 2008

This article describes a methodology to compare the energy benefit that may result from the adoption of two very different facade technologies in non-domestic buildings. A comparison is made of the energy benefit that might result from: (a) replacing conventional glass with electrochromic (EC) glazing; and, (b) installing PV panels across the opaque sections of vertical facade. The energy benefit from electrochromic glazing is predicted on the basis of displaced electric lighting usage against standard glazing with blinds, whereas the energy benefit from facade PV panels is equal to their delivered electrical output. The evaluation setting is a `typical' six metre deep perimeter office space with vertical glazing. Office orientations for each of the four cardinal compass points are considered. Performance evaluations are founded on a full year's hourly meteorological data for fourteen locales across the world. The predicted energy benefit from electrochromic glazing and facade PV are related to the total annual vertical irradiation incident on the building facade. The findings indicate that the energy benefit that results from replacing standard glazing with electrochromic glazing may exceed that of facade PV for the majority of cases studied. Surprisingly, electrochromic glazings are found to provide the greatest energy benefit for those cases at the lower end of the experienced range in total annual vertical irradiation. The effectiveness of widespread deployment across multiple facades for each locale is examined. The likelihood that electrochromic glazing alone can offer sufficient solar protection without recourse to additional shading is assessed using the recently formulated useful daylight illuminance (UDI) scheme.

	Author = {Mardaljevic, J. and Nabil, A.},
	Journal = {Lighting Research and Technology},
	Number = {1},
	Pages = {55--76},
	Title = {Electrochromic glazing and facade photovoltaic panels: a strategic assessment of the potential energy benefits},
	Volume = {40},
	Year = {2008}}
academic/pubs-abstracts.txt · Last modified: 2012/10/23 17:55 (external edit)