02275nas a2200277 4500008003900000245015300039210006900192260001200261300001200273490000800285520134500293653003301638653002101671653001601692653002501708653002001733653001801753653001301771100002101784700002101805700001901826700002401845700002201869700002901891856007701920 2016 d00aBalancing daylight, glare, and energy-efficiency goals: An evaluation of exterior coplanar shading systems using complex fenestration modeling tools0 aBalancing daylight glare and energyefficiency goals An evaluatio c01/2016 a279-2980 v1123 a
Exterior shades are the most effective way to control solar load in buildings. Twelve different coplanar shades with different geometry, material properties and cut-off angles were investigated for two California climates: the moderate San Francisco Bay Area climate and a hot and dry Southern California climate. The presented results distinguish themselves from other simulation studies by a newly developed method that combines three research-grade software programs (Radiance, EnergyPlus and Window 7) to calculate heat transfer, daylight, and glare resulting from optically-complex fenestration systems more accurately. Simulations were run for a case with constant electric lighting and a case with daylighting controls for a prototypical, internal load dominated office building.
In the case of daylighting controls, the choice of slat angle and solar cut-off angle of a fixed exterior slat shading system is non trivial. An optimum slat angle was identified for the considered cases. Material properties (e.g., solar and visible reflectance) did not affect energy use if constant electric lighting was assumed, but they did have a significant influence on energy use intensity (EUI) when daylighting controls were assumed. Energy use increased substantially when an additional interior shade was used for glare control.
10aComplex fenestration systems10aDiscomfort Glare10aEnergy Plus10aEnergy Use Intensity10aExterior shades10aGlare Control10aradiance1 aHoffmann, Sabine1 aLee, Eleanor, S.1 aMcNeil, Andrew1 aFernandes, Luis, L.1 aVidanovic, Dragan1 aThanachareonkit, Anothai uhttps://facades.lbl.gov/publications/balancing-daylight-glare-and-energy00763nas a2200205 4500008003900000245011500039210006900154260003100223653002400254653003300278653002400311653002100335653002500356653001300381100002100394700001900415700002100434700002300455856007900478 2015 d00aDiscomfort glare with complex fenestration systems and the impact on energy use when using daylighting control0 aDiscomfort glare with complex fenestration systems and the impac aBern, Switzerlandc11/201510abuilding simulation10aComplex fenestration systems10adaylighting control10aDiscomfort Glare10aEnergy Use Intensity10aradiance1 aHoffmann, Sabine1 aMcNeil, Andrew1 aLee, Eleanor, S.1 aKalyanam, Raghuram uhttps://facades.lbl.gov/publications/discomfort-glare-complex-fenestration02476nas a2200325 4500008003900000245007600039210006900115260001200184300001200196490000700208520149100215653001701706653001601723653004601739653002201785653001001807653003301817653001301850653001201863100001901875700002301894700001901917700002201936700002801958700002101986700002102007700002102028700002402049856007702073 2013 d00aU.S. energy savings potential from dynamic daylighting control glazings0 aUS energy savings potential from dynamic daylighting control gla c11/2013 a415-4230 v663 aDaylighting controls have the potential to reduce the substantial amount of electricity consumed for lighting in commercial buildings. Material science research is now pursuing the development of a dynamic prismatic optical element (dPOE) window coating that can continuously readjust incoming light to maximize the performance and energy savings available from daylighting controls. This study estimates the technical potential for energy savings available from vertical daylighting strategies and explores additional savings that may be available if current dPOE research culminates in a successful market-ready product. Radiance daylight simulations are conducted with a multi-shape prismatic window coating. Simulated lighting energy savings are then applied to perimeter floorspace estimates generated from U.S. commercial building stock data. Results indicate that fully functional dPOE coatings, when paired with conventional vertical daylight strategies, have the potential to reduce energy use associated with U.S. commercial electric lighting demand by as much as 930 TBtu. This reduction in electric lighting demand represents an approximately 85% increase in the energy savings estimated from implementing conventional vertical daylight strategies alone. Results presented in this study provide insight into energy and cost performance targets for dPOE coatings, which can help accelerate the development process and establish a successful new daylighting technology.
10aClerestories10adaylighting10aDynamic prismatic optical elements (dPOE)10aenergy efficiency10aGlare10aindoor environmental quality10aradiance10awindows1 aShehabi, Arman1 aDeForest, Nicholas1 aMcNeil, Andrew1 aMasanet, Eric, R.1 aGreenblatt, Jeffery, B.1 aLee, Eleanor, S.1 aMasson, Georgeta1 aHelms, Brett, A.1 aMilliron, Delia, J. uhttps://facades.lbl.gov/publications/us-energy-savings-potential-dynamic00704nas a2200181 4500008003900000245014600039210006900185260001200254490001500266653005200281653003200333653001600365653001300381653001500394100001900409700002100428856007300449 2012 d00aA validation of the Radiance three-phase simulation method for modeling annual daylight performance of optically-complex fenestration systems0 avalidation of the Radiance threephase simulation method for mode c05/20120 vApril 201210abidirectional scattering distribution functions10abuildings energy efficiency10adaylighting10aradiance10avalidation1 aMcNeil, Andrew1 aLee, Eleanor, S. uhttps://facades.lbl.gov/publications/validation-radiance-three-phase