Demand is the sum of all electric power required to run a building’s equipment currently in operation. As equipment is turned on and off, demand rises and falls. Peak demand is the highest level of demand recorded by a demand meter during a given time period. This is the most expensive power the utility has […]
NYSERDA sponsored a demonstration project featuring a new Integrated Classroom Lighting System (ICLS) created by Finelite, Inc., a fixture manufacturer, installed as a retrofit into 28 existing classrooms at seven schools and universities. The Lighting Research Center (LRC) assessed teacher and student satisfaction. The result is a design template demonstrated to satisfy audio-visual needs and improve teacher and student satisfaction while reducing lighting power density to an average 0.73W/sq.ft., nearly 50% less than ASHRAE 90.1-2004/2007. Although Finelite optimized the design into an engineered system integrating the company’s light fixtures with state-of-the-art lighting control strategies, the template, if properly designed, can be treated as open source with suitable products from a wide range of manufacturers.
In terms of lighting, ASHRAE 90.1-2007 clarifies the Standard’s intent and enacts several refinements but otherwise doesn’t revise the lighting power density (W/sq.ft.) limits from the 2004 version, which itself was 20-25 percent more stringent than the 1991/2001 versions.
The Energy Independence and Security Act of 2007 (HR6) does not include many provisions directly related to lighting. Two of its provisions, however, are nonetheless highly significant. One virtually eliminates the manufacture of today’s >150W to <500W probe-start metal halide magnetic ballasted fixtures starting in 2009 (replacement ballasts are not affected). Another virtually eliminates the manufacture of most common general-service incandescent lamps, putting billions of sockets up for grabs. The Act also has its eye on a possible LED general-service lamp in the future, establishing incentives to develop an LED product that can take on the 60W incandescent. The Act also distinguishes itself in two other ways. One is what it does not contain, such as encouragement of more-efficient residential energy codes and any tax provisions such as an anticipated extension of the Commercial Buildings Deduction to December 31, 2013. Another is its provisions that may indirectly affect lighting, such as its tough new energy reduction requirements for Federal buildings and the establishment and funding of a Director and Office of Commercial High-Performance Green Buildings, which will work with a private-public partnership to realize a goal of all newly constructed commercial buildings being “net zero energy” by 2030.
What are the benefits of combining advanced lighting control strategies in the same space? Are the energy-saving benefits of lighting controls persistent over time? Can advanced lighting controls be successfully applied to open offices given concerns about jurisdiction conflicts, lighting uniformity, etc.? Can they enhance worker satisfaction? A new office lighting field study addresses these questions. Involving about 90 workers in a real-world open-office environment, the one-year study determined that occupancy sensing, daylight harvesting and individual occupant dimming control worked together in the building to produce average energy savings of 47% while correlating with higher occupant environmental and job satisfaction. The study demonstrates that sophisticated lighting control strategies can be combined successfully to generate persistent, large energy savings in open-plan offices while improving occupant satisfaction with their jobs and workspace.
The study revealed that only 25 percent of the sidelighting photocontrol systems in the studied buildings were functioning well, whereas almost 100 percent of the toplighting photocontrol systems were found to be functioning well in the previous study. What went wrong?
In this special report by the Lighting Controls Association, we will describe bi-level switching code requirements, its role in the Commercial Buildings Deduction, methods and equipment, and the results of a study of typical energy savings achievable with bi-level switching in popular applications.
Dimming of fluorescent lighting offers significant benefits in terms of supporting visual needs with good lighting, giving users control of their own lighting, and energy savings. The advent of digital dimming offers a new option with clear advantages over traditional analog dimming. Digital dimming can be used almost anywhere that analog dimming can be used, for the same purposes: visual needs, personal control, daylight harvesting, scheduling and other control strategies. If fluorescent dimming is desirable for a given application, digital dimming can offer distinct advantages related to intelligence, flexibility and two-way communication.
While today’s occupancy sensors offer robust features, proven utility and reliability, they remain application-sensitive devices, which requires a properly educated designer and installer for the controls to be effective. The right occupancy sensor must be selected, it must be properly located and installed, and it must be field-calibrated.
In this article, we will examine the seven steps of the effective application of occupancy sensors.
The Weidt Group conducted a study of daylight harvesting projects to find out if daylight harvesting projects are living up to their expectations. The team—consisting of Eijadi, Prasad Vaidya, Tom McDougall, Jason Steinbock and Jim Douglas—reviewed dozens of completed projects, most of which were sidelit using windows, and separated the success stories—some of them operating for 25 years—from projects they considered to be failures.