Facility managers (fms) have come to expect it; there will never be a let up in the pressure to reduce operating costs, save energy, improve sustainability, and achieve fast payback on investments in their buildings. These are permanent forces, and skilled managers must find ways to use them to their professional and personal advantage.
Lighting, as noted by U.S. Secretary of Energy Steven Chu, is still the low hanging fruit of energy savings. The four key components of a lighting system—lamps/light sources, luminaires (fixtures), ballasts, and controls—are all gaining rapidly improving technologies which fms can use to their advantage to stop wasting energy used for lighting. Most buildings in the U.S. contain old and outdated lighting systems; but even if a lighting system was renovated five years ago, there is still a significant opportunity to upgrade the system and save even more money.
Fms have a variety of resources they can call on to help evaluate and execute a lighting renovation project. Professional lighting advice can be sourced from lighting designers, architects and engineers, energy service companies (ESCOs), electrical distributors, electrical contractors, and others (see sidebar on incentives below). The scope of a renovation project should drive the decision on which expert to use for professional advice. Rebates and incentives are also widely available, with project payback often between six to 12 months.
Incentives and Other Support
Federal, state, and local tax incentives are commonly available for lighting renovation projects. Here are links to several sources.
EPAct 2005 Commercial Building
Lighting Services Companies
Energy Service Companies (ESCOs)
NEMA enLIGHTen America Initiative
In any case, a lighting renovation involves at least one of the four components of a lighting system. To get started, this article aims to update fms with information so they have the background to ask better questions, understand the options, and achieve the most cost-effective lighting renovation for their facilities.
Incandescent lamps, including the common 60 watt bulb, are being transitioned over the next few years due to federal energy legislation. Replacement options for 60 watt/75 watt/100 watt incandescent lamps include:
- halogens, which save about 17 watts in energy, are fully dimmable, and last about 1000 hours;
- compact fluorescents, which save about 46 watts in energy, and last 10,000 hours; and
- new LED lamps that can reduce energy use by 80%, are fully dimmable, and last 25,000 hours.
Traditional light sources for commercial and industrial settings are high intensity discharge (HID) and fluorescent lamps. These are still valid lighting choices and will remain viable for years to come. Meanwhile, induction lamps have always been an interesting alternative due to their low energy use and long life, and LED technology is rapidly gaining ground for all types of applications. Here is a brief overview of each of the four light sources.
Fluorescent lighting, in commercial use since the mid 1940s, is an inherently energy saving technology. Millions of fluorescent lamps are used in offices, stores, schools, warehouses, and factories. Obsolete T12 magnetic systems have been replaced with longer life T5 and T8 high efficiency electronic systems, but there are still millions of T12 lamps in use wasting a great deal of precious energy resources. Changing out T12 systems should be a top priority for fms.
HID lamps are specified for a wide variety of indoor and outdoor applications. There is a great deal of new HID technology, such as high efficiency ceramic metal halide pulse start lamps, and this lamp type offers a range of colors from warm to bright white. Fms might consider HID lighting for high bay fixtures, retail lighting, façade lighting, and outdoor area lighting. These average 110 lumens per watt, and over time the lamps maintain their brightness well. Expected life is 10,000 to 30,000 hours.
|Legislation Mandates For Lighting
In December 2009, the New York City Council passed major legislation to improve the energy efficiency of existing buildings in the city. Four laws known as the “Greener, Greater Buildings Plan” create a New York City Energy Conservation Code. The legislation addresses the fact that 80% of New York City’s carbon footprint is derived from its one million buildings. Lighting consumes 18% of the city’s energy. Among other aspects, the law requires buildings of more than 50,000 square feet to meet current energy codes by 2025.
Facility managers (fms) in New York City should move quickly and renovate now. If they do, energy savings will be realized sooner than later. Also, tax deductions may expire, and codes may become more costly to comply with by 2025. More information can be found at: www.nemasavesenergy.org and www.conedci.com.
Meanwhile, fms working outside of New York City should be aware that other states and municipalities are studying the “Greener, Greater Buildings Plan” and may adopt part or all of it in the future.
LED technology is gaining ground due to low energy use, reliability, long life, and controllability. It is a replacement light source for ordinary light bulbs, office lighting, and high and low bay lighting in factories and warehouses. LEDs are also popular for downlights, spotlights, façades, and garages. These feature 90 to 100 lumens per watt and show little loss of light levels over 30,000 to 80,000 hours. Initial cost for LED lighting is typically higher. [Read about a supermarket's use of LEDs in "Purchase Power", also in the April issue of TFM.]
Induction lamps are most often used in outdoor applications. With stable color, they offer low lumen loss over 50,000 to 100,000 hours of life, low maintenance, and 70 lumens per watt.
Many offices and retail spaces have obsolete lensed or parabolic troffers, often featuring obsolete T12 systems. New technology includes troffer relighting kits with just two T5 or T8 lamps—or LEDs—which not only reduce energy consumption by 66%, but also provide quality light by eliminating “cave effect,” or dark shadow patterns. Retrofit kits are easy to install, and the long life of these light sources reduces maintenance.
The T5 and T8 lamps and luminaires, along with luminaires for LEDs, are also available for manufacturing and warehouses with both low and high ceilings.
Fluorescent lighting ballasts are a component within a luminaire, but fms should know they play a critical role in energy efficiency and dimming. The maintenance staff should always replace ballasts with a model specified for the fixture, lamp, and system being maintained—and from a reputable manufacturer. Cheap, poorly made ballasts can ruin an entire system.
For instance, high efficiency, NEMA Premium-identified T8 ballasts should always be used with T8 lamps. And when paired with fluorescent lamps that meet new DOE efficiency standards (effective July 2012), this combination may help an organization meet building energy codes and qualify for utility rebates.
The best way to reduce energy use—and costs—is to turn lights off. Lighting controls can turn lights off, dim lights to reduce watts consumed, reduce the HVAC load, and maximize use of sunlight. There are nine basic lighting control strategies fms can employ in commercial, industrial, and institutional buildings, depending on the space and the lamps/luminaires involved.
- Scheduling: Lights automatically turn off or are dimmed at certain times of the day or based on sunrise or sunset.
- Occupancy/vacancy sensing: Lights turn off automatically when people vacate the space.
- Multi-level lighting/dimming: This approach provides users one or more light levels than full on and full off.
- Daylight harvesting: Light levels are automatically adjusted based on the amount of daylight in the space.
- High end trim/tuning: The target light level is set based on occupant requirements in the space.
- Personal light control: This allows users in a space to select correct light levels for the desired task. New wireless dimming technology is particularly applicable to lighting renovations.
- Controllable window shades: This allows users to control daylight for reduced solar heat gain and glare.
- Demand response: Facilities reduce lighting load at times of peak electricity pricing.
- Plug load control: This automatically turns off task lighting and other plug loads when they are not needed.
There is also opportunity to reduce costs in stairwells and parking garages with lighting controls. These infrequently used spaces can consume a high amount of energy for lighting if systems are not as energy efficient as they could be.
Chart A Course
There is no single formula for lighting renovations. Responsible fms must understand their specific opportunities and work with lighting professionals to design solutions that save maximum energy and cost, while also delivering the best light to the task at hand.
Baillie held senior communications posts at Siemens and Acuity Brands Lighting before retiring. He is involved with several groups in the lighting industry, including NEMA and the National Lighting Bureau.