On the Use of Integrated Daylighting and Energy Simulations to Drive the Design of a Large Net-Zero Energy Office Building


Rob Guglielmetti, Shanti Pless, and Paul Torcellini. Fourth National Conference of IBPSA-USA, 2010, pp. 301-309

Review by Scott Schuetter, Energy Center of Wisconsin: 

Daylight modeling and energy modeling have evolved on similar, but parallel, paths. Both are powerful tools that have yet to be married in a seamless way.

This paper is a case study of the impact that these tools had on the design of the National Renewable Energy Laboratory's Research Support Facility, a net-zero, LEED Platinum building on NREL's campus. Specifically, daylight modeling was utilized to analyze the impact of different window head heights, widow-to-wall ratios, glazing transmittance, and interior finishes had on daylight illuminance levels.

LightLouver's Daylight System was also analyzed, showing daylight penetration of up to 60' from the south-facing clerestories. A technique was also developed to integrate Radiance modeling in SPOT with DOE-2 to create a more robust daylight model inside of the energy model. This model showed an overall building EUI of 34 kBTU/ft2/yr. A portion of this low energy usage was attributable to the aggressive daylight harvesting.