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Digital addressable, dimmable lighting controls were introduced to the US market in the early 2000s with the promise of facilitating capture of potential energy savings with greater flexibility over their historic, typically unreliable, analog counterpart. The New York Times Company installed this emerging technology, after having tested the system thoroughly prior to procurement, in their new building in New York, New York. Four years after full occupancy in 2007, the owner agreed to participate in a postoccupancy monitored evaluation of the dimmable lighting system to verify actual performance in the field. Annual lighting energy savings from daylighting, setpoint tuning and occupancy controls were determined for the daylit, open-plan office areas on three typical floors (6, 11, and 20 th floors) of the 51-story high-rise tower. Energy savings were calculated from ballast control signal and occupancy data recorded by the manufacturer's lighting control system. The ballast data were calibrated with independent measurements of lighting energy consumption. Savings from dimming controls (daylighting and setpoint tuning) were 12.6 kWh/m 2 -yr (1.17 kWh/ft 2 -yr) for the daylit spaces on the three floors overall, or 20%, relative to ASHRAE

Exterior shades are the most effective way to control solar load in buildings. Twelve different coplanar shades with different geometry, material properties and cutoff 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 cutoff 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.

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