If you are competing with other research and education facilities in the space of high-end conference and class rooms, high performance LED Lighting may be a good way to provide higher light levels when required and adjust the ambient light level to the task at hand while exceeding the code required maximum watts per square foot.
The right kind of LED lighting, that is flicker free has dimming modulation at 500 Hz or higher well outside any chance of human stroboscopic sensitivity.
Assembly and laboratory spaces as used by universities and other high-tech education and research institutions require high levels of lighting that can be adjusted to the task at hand, very high light levels for critical assembly work, and lower light levels for chemical analysis where too high light levels might influence indicators used in chemical analysis.
The key objective is to provide the specified foot candles for each area while meeting or staying well below the maximum allowable wattage per square foot to pass new commercial building energy codes.
According to Greg Roach, NTEC Director of Education and Laboratory Services, due to the intended use of the spaces being medical device manufacturing and classrooms involving detailed tasks, the specified maximum light levels required on demand were higher than normal office spaces.
You have to have a lighting strategy for your building and look outside the standard lighting representatives portfolio to get a comprehensive and coherent lighting system that satisfies those needs and in that quest you will find that not all LED Fixtures are created equal.
When creating or refurbishing a high-tech education facility biologically optimized lighting should be used. This is generally in the color temperatures between 2700K and 5200K. Higher color temperatures from 6000 to 10,000K are not suitable for classrooms as they have a too high a percentage of polarized near UV blue content that can make some people, that are sensitive to UV light, feel physically sick.
The blue light in LEDs is not hard UV but with a wavelength of 635 nm it is still in the upper end of the UV spectrum and can expose UV sensitive film. If you have flown in a new Boeing 737 aircraft and feel sick or uncomfortable when the blue-white light is turned on before landing, that is the reason why. You may get the same feeling looking down and walking on Orchard Street in Singapore where pure blue high intensity LED strips are embedded in the walkway.
Polarized blue light does not affect all of us but sure some. An education environment should provide the best quality lighting environment possible at the time to the largest cross-section of students possible.
Class Rooms, Auditoriums, Meeting Rooms and long hallways have always been problematic to dim with conventional dimmer and dimming technology for various technical reasons.
A digital dimming system by which each LED Power Supply, also referred to as driver, has a built-in digital dimming can control signal repeater, an infinite number of LED fixtures can be dimmed with one digital dimmer coming from a wall mount, a ceiling mount or a networked controller unit.
Another common problem of conventional dimming is flicker. The LED fixtures that were chosen have a 500Hz modulation rate which is well outside the widely accepted maximum flicker sensitivity of humans in panic of up to 180Hz and animals of up to 230Hz.
If you already have an investment in a lighting management system like a Crestron or others or want to keep the user interface the same with other parts of your facilities, the ability to interface with those systems is important. LED lighting systems provide a Building Management System (BMS) Adapter which allows 0 to 10 Volt input from a Crestron, Honeywell or other system to be converted to the digital signal controlling the LED lighting fixtures. These systems can be upgraded at a later time to a more comprehensive Lightspace and Energy Management System.
In some areas a significant reduction in energy use could be achieved by using motion sensors built into the fixtures or multiple ceiling mount sensors feeding into each other controlling a string of up to 40 fixtures.
Range of Fixtures
For NTEC, ActiveLED provided all the fixture types required for the building from Round Ceiling Down Lights in 4″, 6″ and 8″ diameters, 2′ x 4′ and 2′ x 2′ ceiling drop-ins with 72 Watt as well as 75 Watt and 150 Watt round High Bay lighting for the Warehouse and Prototype Manufacturing Area. All were dimmable using Lightspace digital controls in combination with a conventional 0 to 10 Volt dimming system.
Cost of Ownership
For a new build or a total refurbishment the Cost of Ownership is most important. LED light fixtures can provide warranties of 10 years with guaranteed light levels of 90% of the original light-level. This translates into a very low-cost of maintenance, whereas in the past re-lamping had to be put into any budgetary planning at least every 3..5 years, with LED light fixtures it may now be budgeted for a 10..12 year replacement or overhaul.
In trials many of the Fluorescent Tube replacement LEDs do not provide the required light output and if they do they do not last very long and sometimes shorter than a fluorescent tube. Screw-in or PAR 38 LED replacements of high wattage do not last very long and can not produce the same lumens per watt as their FL counterparts. Replacement lamps and tubes are generally not or only poorly dimmable with varying results from light bulb to light bulb or tube to tube.
Fluorescent Tubes, HID and Induction Lighting contain levels of Mercury that are highly poisonous. Cost of disposal will continue to increase and so will the requirement to keep students safe from exposure from mercury due to accidental breakage.
The best experience is with LED light fixture replacements rather than bulb or tube replacements. LED light fixture replacements use the whole fixture to dissipate the heat thus eliminating the issue of LEDs and heat. Fixture replacements have demonstrated that it is possible, to have no light loss nor any increase in energy use after 5 years of constant use as well as tens of turn-on / off cycles per day in covered parking applications the same 5 year period.
The energy used to light a place ends up completely in heat. It takes the same amount of money for energy to cool a place as you spend lighting it. So every $ saved in indoor lighting is an additional $ saved in air-conditioning.
Overall budgetary planning will still have to consider 3 to 5 year cycles as other parts like furniture and decoration may ware-out faster in high use areas. By implementing highly performing and performance guaranteed lighting systems at least during one or two budget cycles other high-tech advancements can be budgeted for improving the competitiveness of the facility and the productivity of research and students.