4 FM quick reads on lighting
1. LEDs: Specification Challenges
This is Chris Matt, Managing Editor of Print & E-Media with Maintenance Solutions magazine. Today's tip focuses on lighting with light emitting diodes, or LEDs.
Few technologies have seen as much change — and gotten as much attention — in the last few years as LEDs. Despite the presence of this technology for decades, LEDs recently have entered the lighting market for institutional and commercial buildings and established a foothold faster than any other source available.
The increased lamp life and energy efficiency the technology offers has caught the attention of maintenance and engineering managers, as well as other lighting specifiers, but LEDs do face hurdles and challenges.
The tallest hurdle facing the LED industry is price. LED=based lighting fixtures can cost 1.5-2.5 times more than their traditional counterparts. In some cases, managers might be able to recoup the higher initial cost through energy savings or lower maintenance costs.
Factors such as luminaire spacing, orientation and desired uniformity of the lighting levels create a unique set of criteria for each project. Rarely is the decision to use LEDs a hands-down winner over more traditional technologies. More often, the decision relates to the traditional, or base-case, application to which the LED system is compared.
LEDs have entered the lighting market at break-neck speed, and standard-setting groups have struggled to keep pace with the change. Published works defining standards for comparing life and output of LED systems have not been sufficiently updated.
Without clear definitions and guidance, managers and other specifiers have struggled to get a clear picture regarding LED performance. Many have been burned by early adoption of LEDs. Most designers and engineers believe the best way to select LEDs is through mock-ups and real-world installations.
Specifiers often elect to view a sample to judge first-hand whether the product under consideration will meet their criteria. Subtle variations in color temperature, color rendering and light distribution tend to get lost on cut sheets and photographs. The variety of energy savings potential drastically affects LED products during a life-cycle cost comparison.
New and Established Automation Companies Offer Energy Options
A spurt of innovation is offering new options for automating buildings to save energy.
Energy efficiency has become a high-profile national issue, driven by concerns about climate change and volatile energy prices plus a growing desire of businesses to present a green image. Those factors help explain why established building automation system providers are expanding their offerings, while new companies are entering the market.
Those new companies aren't limited to building automation providers. Some start ups offer products designed to improve control of lighting systems, including LEDs. Other start ups target building automation. This new generation of start-ups includes companies funded by venture capital and it draws talent from around the world.
In part these innovations are driven by advances in technology from outside the building automation arena. Faster, cheaper information processing power is one example. Another is the advance of touchscreen technology, which has now become available for use with building automation systems.
One area where technology development is evident is with energy dashboards. These fall into two categories. One type of dashboard reports on energy use in the past. These dashboards can be used to monitor and report on energy consumption for facility management purposes or to educate occupants or visitors about a building's energy use.
Another type of dashboard provides real-time energy information, reports Lindsay Audin, president of EnergyWiz and a contributing editor for Building Operating Management. These dashboards receive energy-use data from utility "smart meters" and present it in graphical form so that it can be grasped quickly. Information may include how fast power, fuel or energy dollars are being used; load profiles; and comparisons of past and present energy use. Facility managers can use the dashboards to find problems with HVAC systems and controls that are wasting energy and money. Some dashboards can help with demand response or fuel switching efforts.
Lighting Controls: Daylighting and Dimming
This is Chris Matt, Managing Editor of Print & E-Media with Maintenance Solutions magazine. Today's tip is strategies for daylighting and dimming.
Daylight is a highly desirable light source and provides opportunities for energy savings. When sufficient daylight is present, control systems can turn off or reduce lighting in steps or through dimming in a slow, continuous manner.
Studies reveal occupants who are stationary and perform critical tasks, such as open offices, prefer dimming to happen slowly so they do not notice it. Stepped switching can be jarring and break a person's concentration, but it can work well in public-transition spaces, such as lobbies.
Not every light source is dimmable, so managers need to coordinate the lamp type with dimming options. The appropriate ballast or driver can dim most fluorescent and light-emitting-diode, or LED, sources. Some metal-halide lamps are also dimmable, but they usually have a smaller dimming range with more color shift, so they might be inappropriate for some spaces.
Technicians can install photocells on ceilings, walls, light fixtures or the building's exterior to control the flow of electricity based on the amount of daylight measured as reflected from task surfaces or entering the space at the daylight apertures, such as windows. Managers need to consider the location of photocells carefully to ensure they read the available daylight at a meaningful location.
Photocells also require calibration in the field to make sure they trigger lights at appropriate settings. Most products have factory presets, which technicians can adjust in the field or remotely, in the case of some digital control systems. Technicians also should test them periodically to see if adjustments are necessary.
Successful Lighting Retrofits
I'm Dan Hounsell, editor of Maintenance Solutions magazine. Today's topic is, successful lighting retrofits.
Commercial and institutional facilities measure the success of building retrofits in a variety of ways, including cost savings, reduced energy use, and improved occupant productivity and satisfaction.
One important indicator that is difficult to quantify is the level of interest from peers outside the organization. A prime example of this dynamic is occurring at the University of California, Davis, where lighting retrofits are garnering a great deal of attention.
The university's Smart Lighting Initiative has turned the campus into something of a lighting laboratory, thanks in large part to the university's relationship with the California Lighting Technology Center, a demonstration and education facility on campus that develops energy-efficient technologies. Chris Cioni, the university's associate director of utilities, uses lighting center staff as a sounding board when considering cutting-edge lighting technology for retrofit projects. Cioni, his team, and the lighting center joined forces in retrofitting fixtures in campus parking structures and surface lots. Their next set of projects will focus on pathways, roads, and fixtures on building exteriors.
The opportunities for savings are great, considering the number of exterior fixtures on campus — 2,300 fixtures in parking structures and surface lots, as well as 700 fixtures on roads, 1,300 on pedestrian and bicycle paths, and 3,000 on building exteriors.
The university spent almost $1 million retrofitting fixtures in its surface lots and parking structures, which generated about $300,000 in utility rebates. The projects have resulted in a host of additional benefits, including energy savings, reduced maintenance, and improved safety.