Lighting
Best Practice Embraces Efficiency and Innovation Including daylight harvesting
The most advanced lighting systems use an occupancy sensor system, and photo sensor daylight harvesting to save energy. [1] Luminaires, whether a few or many, can be connected to digital lighting control systems, such as iGEN, to improve lighting performance. [2] [courtesy Lightolier] Some companies can fit their luminaires with integrated controls to help reduce and monitor energy use. [courtesy Axis Lighting] [3] T5/ T5HO fluorescent bulbs and T8 bulbs, with 5/8-in. and 1 in diameters, respectively, are highly efficient and can be placed in smaller spaces. [4]
J. Lynn Fraser .Rising energy prices, legislation, and a deepening awareness of global warming issues are propelling innovation in lighting design and manufacturing. The industry now views lighting and systems design as a collaborative process and the use of lighting by building occupants as being multi-layered. Energy efficiency, environmental responsibility, and innovation are now central to the lighting industry’s best practices.
Energy Efficiency
In a recent study, the Intertech-Pira Research Group estimated that “up to 59% of the $230 billion annual cost of global lighting energy, can be saved through the adoption of energy-efficient lighting technologies.”(1)
Energy efficiency and environmental responsibility mean designing for the interaction of the physical components of the building with the occupants while considering carbon emissions and energy consumption. Available daylight, task requirements, and location are all considered when designing for sustainability. This consideration of individual user’s needs now extends to commercial buildings, where previously high levels of general lighting were typically the norm.
This reflects a growing “light awareness” according to Mark Lien of Hubbell Lighting’s Lighting Solutions Center. Office spaces, for example, would usually be lit from ceiling to desk with 40 to 50 foot candles [lumens/sf] of light. The trend now is toward 20 foot candles, and adding task lighting while lowering light levels in areas of infrequent use.
By contrast, retailers have typically used incandescents as they produce high contrast pools of light to focus attention. But, according to Lien, retailers now have the option of using small metal halide lights that, although six to eight times more expensive to purchase, ultimately provide savings because of their long service life.
New lighting technologies, while more efficient, still contain mercury. Metal halides, for example, contain approximately 70 milligrams of mercury whereas T5 and T5HO fluorescent lamps have about 10 milligrams. Mercury-containing lamps should be separately recycled and some retailers now offer this service.
Some manufacturers offer more environmentally friendly alternatives. Steve McGuire, Environmental Marketing Manager for Philips Lighting, notes that Philips has created an integrated, screw-in 25-watt ceramic metal halide with low toxicity levels that can replace traditional 75 to 90 watt incandescent lights. They do not require special ballast or fixtures and last for 10,500 hours.
Sustainability for Dan Blitzer of the Philips Application Center, “means meeting the needs of people in a building within a sustainability context.” The context will determine best practices for each application.
Energy efficiency requires taking into consideration a building’s overall consumption while also calculating factors affecting variations in consumption. Lighting in buildings accounts for 20 to 40% of total power use says Darrin Hoyle of Cooper Lighting. Decreasing power consumption and lighting loads is an important part of lighting design, and can be achieved by following the industry’s best practices.
Best Practices
Design of lighting installations should consider peak consumption periods, length of occupancy in rooms, as well as daylight harvesting. “The best lighting system,” he suggests, uses a variety of controls: an occupancy sensor system, dimming ballast, and photo sensor daylight harvesting” monitored by a control network. Peter Horton of Watt Stopper Inc. agrees, noting that as “commercial buildings create 33% of carbon emissions any building over 5,000sf needs automatic shut off timers and motion detectors.”
Choosing lighting specific to the task, the individual, and the location is of growing importance in the lighting industry. Dan Blitzer stresses the importance of: “task ambient lighting design, a non-uniform approach, and lighting vertical surfaces and work stations as well as local [individual] control.” All of these approaches mean a focused use of light that reduces overall energy consumption.
Like many, Michael Bolton of Douglas Lighting Control advocates taking advantage of daylight through perimeter windows and skylights. “Demand-response,” another solution Bolton suggests enables utilities “to offer savings to users who allow electrical load to be reduced in peak periods. Both the utilities and the design community would have to work together to build that functionality into systems.”
Retrofitting is another important energy saving strategy. Terry Hoffman and Steve Thomas of Johnson Controls note that their company is responsible for more retrofitting than any other manufacturer in North America and recycles more light systems. Mike Bolton also sees the importance of working with a building’s energy efficiency and lighting system throughout its lifespan. He notes that some renovators do not reconnect control and occupancy systems, thus affecting the building’s energy efficiency for future tenants.
Best practices must also embrace the industry’s manufacturing infrastructure. Hansi Mueller at SELUX notes that in their powder coating paint booth 98% of the paint is used, 80% of their water is recycled, and CFCs have been eliminated. Mark Lien reports that Hubbell’s head office is certified LEED silver, and is the only lighting manufacturer with carbon neutral manufacturing.
On this same theme, Morris Feldman of Axis Lighting says their light fixture extrusions can be made of up to 80% recycled aluminium [60% post-industrial, 20% post-consumer], including an electro-static and recyclable powder coat finish. Their fixtures are designed for disassembly, with components having the opportunity of being reintegrated into the production cycle.
Technical Innovations
T5/ T5HO fluorescent bulbs that are 5/8-in. in diameter, and the high-efficient 1in. diameter T8s, are cited by Dan Blitzer as “innovative light sources that allow for light to be collected more efficiently due to their small size.” The size of both enables them to be placed in smaller spaces. Metal halide lamps, a high intensity discharge lamp, are also noted by Blitzer as an energy efficient alternative. With a long lifespan they are highly efficient, and offer good colour and optical control with a source of light equal in size to a ball point pen at 3/8-in. in diameter and 1/2-in. in length.
In the future, Mark Lien sees a significant role for solid-state lighting such as organic light-emitting diodes [OLEDs] that currently offer around 30 lumens per watt. He predicts their prices will fall in the future. Additionally, he sees a future role for light emitting capacitors [LECs]. Their size, for example
3 ft. x 6 ft. panels, and their physical flexibility make them an adaptable technology although, Lien notes, they have lagged behind in performance.
Quantum dots technology, based on carbon nano crystals, is one to watch in the future. The size of the dot and the amount of stimulation it receives affects the intensity of the light it gives off. The smaller the dot, the higher the energy and intensity of its emitted light.
A dot’s colour depends on its size. LEDs can be made from Quantum dots, and the dots can also be used for indoor lighting. (2)
The most important trend in lighting technology is the move towards systems. Osram Sylvania started this movement with The System Solution®, a family of optimally balanced energy saving lamp and ballast combinations. This trend is now being extended with LED systems that are being used for signage applications due to their sturdiness, reliability, long life, energy efficiency and low maintenance. They have also opened new avenues in lighting with their colour mixing and colour sequencing capabilities. They offer unique capabilities for architectural enhancements and decorative lighting due to their small sizes and system flexibility.
To ensure that lighting design and systems are energy efficient and environmentally responsible lighting must be seen as affecting more than the immediate area it illuminates. The science and psychology of lighting design must also take into account the micro and macro environment of the building and the profound effect lighting can have on the health and comfort of occupants.
J. Lynn Fraser is a Toronto-based writer who specializes in design and construction subjects. .
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Manitoba Hydro Headquarters
Lighting design brings big energy savings
KPMB Architect’s The Manitoba Hydro headquarters under construction
in downtown Winnipeg is an example of the integration of best practices, energy efficiency, and environmental responsibility in one building.
The building comprises 700,000sf and will be “one of the most energy efficient large-scale buildings in the world,” according to KPMB Architects. Energy savings are projected to come in at 60%.
“Lighting is a major source of the energy reduction in the building,” according to Kael Opie, KPMB’s Project Architect for the Hydro project. One of the key features of the design of the building was the Integrated Design Process [IDP] which brought architects, consultants and engineers together intensely at the schematic level, including the Transsolar company from Stuttgart.
The building is based on an A-shape plan, with shallow flanking office loft spaces measuring 11m wide from the core to the face of the building. Large atriums in the north and south help natural light to penetrate deep into the core.
The building will use an automated blind system that can be adjusted to shade and bounce light up to the ceiling and reduce glare. Louvered and roller blinds will be tied to light sensors programmed to adjust to seasonal and immediate daylight changes.
The Manitoba Hydro building treats light, the physical environment of the building, and the needs of the occupants as an interactive process that lighting must adapt to. Ergolight, an intelligent and personal controllable light system from Ledalite, featuring both direct and indirect lighting and employing built-in occupancy sensors and photosensors, will contribute to efficient daylight harvesting. Direct lighting will illuminate work surfaces, while the indirect lighting will serve the surrounding areas. Each individual fixture is linked to a local area network, allowing individuals the potential to use their computers to turn lights on and off, and to set dimming levels.
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