Tag Archives: lighting

The Drive Toward Energy Efficiency

Energy-efficient light-emitting diodes (LED) luminaires provide consistent light levels for increased visibility and a secure environment.

Energy-efficient light-emitting diodes (LED) luminaires provide consistent light levels for increased visibility and a secure environment. Photos © Kelly Lee Flora Photography

By Jeff Gatzow

The parking lot at the National Corvette Museum in Bowling Green, Kentucky has upgraded its illumination with light-emitting diodes (LEDs) to improve light quality and provide better lighting control.

Located across the street from General Motor’s Bowling Green Corvette assembly plant—the only place in the world Corvettes are made—it was constructed in 1994, and showcases more than 70 Corvettes.

Visitors can see mint-condition classics, one-of-a-kind prototypes that never went into production, racetrack champions, and modern-day wonders of engineering and design. Attendees also have the opportunity to interact with educational hands-on exhibits, enjoy a film in the theater, and see rare collectibles and memorabilia.

Lighting upgrade
The museum’s upgrade to its three parking lots with LED luminaires was a one-for-one replacement—17 1000W metal halide fixtures were replaced with the same number of 240W LED luminaires. Also, 27 400W metal halide fixtures were switched to 27 120W LED luminaires. At the time the decision to retrofit the parking lots’ lighting was made, the museum had two key priorities for the upgrade: improve the quality and color rendition of the lighting, and enhance control of lighting energy use while maintaining or improving the lot’s safety.

The LED luminaires provide consistent light levels for the entire parking lot, reduced hazardous waste disposal, and provide more efficient light distribution than the metal halide fixtures. Additionally, these luminaires are virtually maintenance-free, offering another opportunity to further reduce expenses.

“The exterior lighting allows us to dramatically reduce operating expenses,” said Bob Hellmann, the museum’s facilities and displays manager. “Additionally, the new lights help make the parking lot bright and secure.”

The retrofit of these 44 fixtures is expected to save the museum $9300 annually in energy expenses and virtually eliminate the $2000 spent in annual maintenance and repair for the incumbent metal halide fixtures. The National Corvette Museum will have a payback of only three years. Further, the utility company, Tennessee Valley Authority, provided $9350 in incentives for the upgrades.

Commitment to sustainability
The National Corvette Museum is committed to sustainability through several green initiatives with the goal of enhanced energy conservation and lessening its carbon footprint. Through these efforts, the museum not only realizes bottom line cost savings, but also works to strengthen business relationships and inspire environmental action by the facility’s patrons.

In addition to the recent retrofit of exterior LED luminaires of the parking lots, the museum has also upgraded other exterior and interior building fixtures to further reduce energy costs and improve the quality of lighting.

“The energy-efficient lighting allows us to drive down operating expenses, present our cars and exhibits in the best light, and contribute to the greening of our community,” said Hellmann. “We installed the LED luminaires and the more efficient fluorescent lights because they pay back in so many ways and it’s the right thing to do.”

Recently, the museum was the site of a 12-m (40-ft) wide 6-m (20-ft) deep sinkhole that swallowed eight vehicles and caused extensive damage.

Before the light-emitting diode (LED) upgrade, metal halide fixtures consumed a lot of energy and required ongoing maintenance at the National Corvette Museum in Bowling Green, Kentucky.

Before the light-emitting diode (LED) upgrade, metal halide fixtures consumed a lot of energy and required ongoing maintenance at the National Corvette Museum in Bowling Green, Kentucky.


Jeff Gatzow is national sales and marketing manager, lighting with Optec LED. The California-based supplier of high efficiency LED lighting fixtures feature a patented thermal management system for cool operation and extended life. Gatzow can be reached by e-mail at jgatzow@optec.com.

Industrial Daylighting

Increasing light quality and reducing energy load

All images courtesy Acuity Brands

By Brian Grohe

For an electrical conduit design and manufacturing company in Roselle, Illinois, a new plant would represent as much as a 60 percent increase in company production and 25 new jobs in the community. However, before expanding manufacturing operations to a 4923-m2 (53,000-sf) space, there needed to be major changes to the 14-year-old building.

The building would be reclassified from industrial to heavy manufacturing, and it would be made as environmentally sound as possible. This meant improved energy efficiency where it was most achievable—in the building’s thermal properties and lighting system. Specifically, the company wanted vegetated roofing assemblies, lowered indoor temperatures, and improved energy efficiency, as well as daylighting solutions.

Two years ago in another project, 15 skylights were retrofitted with new ones from a California-based manufacturer specializing in high-performance prismatic skylights for the commercial market. Having seen the enhanced performance of those skylights, project manager Ed Berbeka opted for them again.

This photo shows the 55 to 62 footcandle (fc) readings inside the facility after the installation of prismatic skylights.

This photo shows the 55 to 62 footcandle (fc) readings inside the facility after the installation of prismatic skylights.

A total of 56 skylights were installed in the Roselle facility last October, at the same time the insulation and new roofing was installed. For the insulation upgrade, R-25 insulation would meet the latest international standards for long-term, thermal-resistance values. For the roofing upgrade, the existing ethylene propylene diene monomer (EPDM) black membrane was replaced with more reflective white—and more energy-efficient—thermoplastic polyolefin (TPO) material. The TPO assembly, lightweight and time-tested since the mid-1970s, reflects the sun’s rays to reduce incoming heat, and does not require rock ballast.

New electrical and energy-efficient lighting was also part of the upgrade to the building. After the roof renovation, the building’s interior temperature decreased by an estimated 17 C (30 F)—a measure taken during the month of August, just before the entire project was completed.

Lighting also significantly improved. The new skylights cover three percent of the roof area, which is relatively standard for industrial buildings. Thanks to their prismatic properties, however, the lighting inside the building, which has a ceiling height of about 12.19 m (40 ft), is anything but standard.

Generally speaking, warehouse lighting varies from as few as 5- to 10-fc (footcandles) in inactive storage areas, to as much as 30- to 40-fc output in more active spaces such as loading docks or receiving areas. After the installation of the skylights, light-level readings in the building reached from 55 to as much as 62 fc—without any use of electrical lighting.

A new roofing membrane and insulation to reduce the HVAC load were installed.

A new roofing membrane and insulation to reduce the HVAC load were installed.

The electrician took note of the lack of ‘hot spots’ created by typical bubble-dome skylights, which can allow heat to build in the space below. The specified skylights, however, diffuse the incoming light through its prismatic lenses, eliminating hot spots, glare, or haze, as well as dissipating any heat. All that remains in the space is fully captured, evenly distributed and ultraviolet (UV)-stable daylighting coverage.

In addition to increasing the interior light source and providing increased energy savings, the building owner says the daylighting solution also boosted employee morale in the manufacturing plant.

Brian Grohe, LEED AP, is the corporate accounts manager–industrial for Acuity Brands. He holds a bachelor’s degree from Columbia College in Chicago. With more than nine years in the daylighting industry, Grohe has held roles in regional sales and business development. He can be contacted by e-mail at brian.grohe@acuitybrands.com.

LED Luminaires Provide Lesson in Energy Savings: Current initiatives

There are hundreds of initiatives, both grassroots and national, to help transform the nation’s approximately 13,900 public K–12 school districts to reduce energy costs and consumption, and lessen their carbon footprint.*

Mayors’ Alliance for Green Schools
Recognizing sustainability in schools must come from grassroots efforts. The Mayors’ Alliance for Green Schools unites mayors from major cities and small towns across the country around the common goal of bringing the benefits of green schools to local communities.

The program was initiated in October 2008 by two mayors—Manuel A. Diaz of Miami, and Greg Nickels of Seattle. It works in conjunction with U.S. Green Building Council (USGBC) and its national network to harness the leadership and creativity of local community leaders nationwide.

A major initiative of the group is the development of public-private partnerships (P3s) with local businesses to enable schools to install vegetated roofs and solar panels, implement recycling and sustainable purchasing programs, and advance other green improvements.

Participating mayors also champion innovative legislation to promote the construction and retrofits of green schools and related projects, such as safe biking and walking routes for students, developing and integrating green curriculum, and making facility operations and maintenance more efficient.

Green Schools Alliance
Created by schools for schools, the Green Schools Alliance (GSA) is a global network of sustainability coordinators—faculty, staff, students, and administrators—working together to solve environmental and climate challenges. GSA member schools share and implement sustainable best practices, and promote connections between schools, communities, and the environment by offering programs, exchanging resources, and creating peer-to-peer forums.

The GSA has an annual competition, Green Cup Energy Challenge, which is the largest national electricity use reduction competition among K–12 schools. This year, students from 120 schools across the country competed to reduce energy consumption. The challenge, now in its sixth year, is designed to raise awareness about energy conservation and provide concrete action towards reduction.

The Congressional Green Schools Caucus
The Congressional Green Schools Caucus, now approaching 70 members, was formed as a way to educate and inform members of Congress on the impact they have on the nation’s sustainability approach to new and existing school buildings. With support from USGBC, it empowers federal legislators to make schools greener.

The caucus hosts regular briefings on the benefits of green schools, supports policy discussions, creates opportunities for caucus members to work to advance legislative and programmatic goals together, and equips members of Congress with resources for constituents. Caucus members and their staff also participate in educational programs to learn what is going on nationally and in their districts, including site visits to green schools and educational panels with teachers, architects, and school officials from across the country.

* For more information, see U.S. Department of Energy’s (DOE’s) Buildings Technologies Program book, Guide to Operating and Maintaining EnergySmart Schools.

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LED Luminaires Provide Lesson in Energy Savings

Photos courtesy Kenall Lighting

Photos courtesy Kenall Lighting

by Mark Bolton, IESNA

A distressing fact faces those who operate K–12 educational institutions across the country. According to the U.S. Department of Energy’s (DOE’s) and Environmental Protection Agency’s (EPA’s) EnergyStar, primary and secondary schools are spending a staggering $6 billion annually on energy—more than on textbooks and computers combined. This equation is disturbing, and there are ways to lower schools’ utility costs.

According to the U.S. Green Building Council (USGBC) Build Green Schools website:

If a green school saved $100,000 per year in operational costs, it is roughly enough to hire two new teachers, buy 200 new computers, or purchase 5000 new textbooks.

Additionally, USGBC has determined if all new school construction and renovations went ‘green’ today, energy savings alone would total $20 billion over the next decade.

California is the nation’s largest school system with more than 10,000 schools, 70 percent of which are more than two decades old. According to the California Energy Commission, schools in the state spend $700 million a year—or nearly three percent of their total budget—on energy. By employing energy efficiency in the state’s schools, the system could reduce energy bills by 20 to 40 percent, leaving funds for other educational priorities.

The following statistics are notable:

  • according to EPA, the average school retrofit reduces energy costs by approximately 30 percent;1
  • more than 80 percent of average school energy consumption is used for heating, cooling, ventilation, and lighting systems;2
  • energy improvements, such as increased daylighting, have the potential to save schools $1.5 billion annually while simultaneously creating a better learning environment; and
  • the country’s least energy-efficient schools use nearly four times as much energy per square foot as the most efficient.3

Additionally, DOE’s Guide to Operating and Maintaining EnergySmart Schools suggests nearly one-third of the energy consumed in the average U.S. school is wasted. For example, gymnasium and stairwell lights are left on at full brightness during periods of non-occupancy. This wasted energy consumption can be easily addressed through use of sensorlight-emitting diode (LED) lighting systems, which translate into cost and energy savings to the school.

The good news is energy is one of the few expenses that can be decreased without negatively affecting classroom instruction. By implementing improved operations and maintenance strategies, and incorporating efficient equipment into retrofits, school districts can generate substantial cost savings while improving the physical environment for students and teachers alike.4

Moving the needle
The U.S. Department of Energy has calculated lighting in institutional facilities can consume up to one-third of a building’s total energy cost. Traditionally, lighting has been viewed as a fixed expense, but this statistic, combined with technology advances and engineering, means lighting can be given a closer examination as a budgetary line item.

Former U.S. Secretary of Energy, Steven Chu, has repeatedly said, “Energy efficiency isn’t just low-hanging fruit; it is fruit lying on the ground.” To that end, one of the quickest return-on-investments is retrofitting traditional lighting fixtures with LED luminaires.

DOE has heralded LEDs as the future of lighting because they have an extremely long lifespan when compared to fluorescent lighting, in many cases lasting 10 times longer.


LED background and advantages
LEDs have been around for more than 40 years. The small, solid-state devices can be used to produce millions of different colors and brightness of light, while using less energy than traditional lighting methods.

LEDs fall under solid-state lighting (SSL) technologies. The term solid-state refers to the fact the light in an LED is emitted from a solid object (i.e. a block of semiconductor), rather than from a vacuum or gas tube, as in the case of incandescent and fluorescent lighting. Solid-state refers to electronic components, devices, and systems based entirely on the semiconductor.

LEDs create light differently than conventional forms. Other lighting technologies, such as halogen and incandescent sources, heat up a fragile filament until it radiates light, wasting large amounts of electrical energy through infrared radiation. Conversely, LEDs convert an electrical current directly into light so less energy is wasted. LEDs do not burn out as a standard lamp does, so individual diodes do not need to be replaced. Instead, the diodes gradually produce lower output levels. In fact, well-designed fixtures can last up to 50,000 hours or longer; further, when one LED fails, it does not necessarily result in a complete fixture outage.

Due to their long life, LEDs are virtually maintenance-free and the energy savings they represent is often quite dramatic. LEDs also re-strike instantly after a power interruption and can be controlled with occupancy sensors. Well-designed LED luminaires may operate between 50,000 and 100,000 hours, and deliver at least 70 percent of their initial performance at their ‘end of life.’

Lumen maintenance describes how long a lighting fixture retains a certain percentage of its initial light output. White light sources, such as LEDs, used for general illumination are commonly considered to be at the end of their useful life when the light output falls below 70 percent of initial output.

LEDs are solid-state devices containing no moving parts, no filaments, or fragile glass to break—this eliminates the risk of damage during transportation, installation, and operation, even in the toughest environments such as public access areas where fixtures are routinely subjected to attempts of vandalism and abuse. Additionally, as explained above, LEDs have longer lifespans than various other traditional light sources.

LEDs are considered more sustainable because they decrease the need for additional power plants, which cause the release of potentially damaging carbon dioxide (CO2) into the atmosphere. Additionally, LED luminaires have an environmental advantage as they contain no mercury and are Restriction of Hazardous Substances (RoHS)-compliant.

RoHS restricts the use of lead and other materials in electronic component products. The program’s purpose is to reduce the influence of these substances on the environment.

Since LEDs do not contain significant amounts of harmful components and are RoHS-compliant, they can be disposed of and recycled in the same way as an ordinary light bulb. Additionally, some manufacturers offer product recycling to customers at the end of the LED’s lifetime. At least 80 percent of the luminaire’s material by weight is recyclable at end-of-life and is designed for disassembly per International Standards Organization (ISO) 14021, Environmental labels and declarations–Self-declared environmental claims (Type II environmental labelling).

High-source efficacy (i.e. lumens per watt)
Efficacy is a term normally used in cases where input and output units differ. In lighting, the amount of light (in lumens) produced by a certain amount of electricity (in watts) is the concern. Significant advances in LED efficacy have recently been introduced by suppliers. As a result, the lumen output of these LEDs has substantially increased. How long is 100,000 hours? Based on the length a fixture is illuminated per day, the translation of a 100,000 hour lifetime into an annual basis can be seen in Figure 1.

LEDs in action
With more than 350 schools covering more than 2.2 million m2 (24 million sf), the Clark County School District (CCSD) is the fifth largest and fastest growing school district in the United States. CCSD’s Facilities Division is also one of the most comprehensive, sophisticated, and sustainable design-oriented districts. They are in the process of building more than 100 new schools to meet the tremendous growth of the greater Las Vegas metro area. All of the new schools will target Leadership in Energy and Environmental Design (LEED) Gold certification.

The light-emitting diode (LED) lights are an alternative to traditional high-intensity discharge (HID) fixtures and are helping Ed W. Clark County High School to reduce its energy consumption by 75 percent.

The light-emitting diode (LED) lights are an alternative to traditional high-intensity discharge (HID) fixtures and are helping Ed W. Clark County High School to reduce its energy consumption by 75 percent.

In addition to this new construction, the district is implementing extensive renovation and modernization at existing facilities, such as Ed W. Clark High School. Built in 1964, the high school serves approximately 2070 students. Steve Johnston, CCSD design manager for the modernization project, is overseeing the ongoing $30-million renovation that includes:

  • HVAC and plumbing upgrades;
  • locker room improvements;
  • food service kitchen;
  • science labs;
  • fire/sprinkler system;
  • technology advances such as local area network (LAN) and classroom projector installations; and
  • daylighting in the student activity center.

Additionally, because of a federal grant, an upgrade to the inadequate and outdated exterior lighting system was considered.

Working with Johnston on this renovation was Jeff Iverson from TJK Consulting Engineers. Wanting to reduce energy consumption and costs, Johnston and Iverson looked into LED luminaires compared with other lighting technology but found no comparison regarding the efficiency or quality of illumination. Previously, the school had 91 of the 70-Watt high intensity discharge fixtures installed in overhangs and doorways. In a one-for-one replacement, the school now has the same number of 23.1-Watt LED canopy and wall-mounted exterior luminaires—almost a full replacement of exterior luminaires on the school grounds. This LED installation is reducing the school district’s energy consumption by 75 percent over the incumbent fixtures.

Providing a safely illuminated campus during evening hours was also an important reason for selecting new lighting.

Reduced luminaire maintenance is a benefit welcomed by Jack Viscosi, CCSD’s electrical/mechanical repair coordinator, responsible for the electrical maintenance at Clark High School. The lifetime of an LED, approximately 100,000 hours, allows for increased performance and reduced maintenance compared to traditional lamp sources.

Las Vegas has a dry desert climate leaving little moisture in the air to retain daytime heat resulting is low night temperatures. LEDs can thrive in cold environments, unlike fluorescent light whose performance is greatly affected by cold temperature.

This is the CCSD’s first LED luminaire installation, but it will not be the last. A commitment to reducing energy consumption and environmental stewardship will help facilitate additional sustainable projects as funds become available.

The $30-million renovation is funded largely through a 1998 voter-approved bond fund, and federal grants specifically for the lighting upgrade, as well as a solar thermal grant for the installation of an adsorption chiller in the central plant to control the school’s cooling.

According to the U.S. National Center for Education Statistics (NCES), there are currently 98,706 public schools and 33,740 private and parochial schools in the country. The amount of resources that could be redirected toward education, hiring teachers, and buying necessary classroom materials if an energy-efficiency program was implemented is clearly sustainable.

DOE reports state and local agencies are planning to invest more than $60 billion over the next three years to build or renovate schools. Now is the time for schools to employ more sustainable products, such as LED luminaires, as a catalyst to significant improvements in energy efficiency.

1 For more, see the U.S. Environmental Protection Agency’s (EPA’s), Energy Efficiency Programs in K–12 Schools: A Guide to Developing and Implementing Greenhouse Gas Reduction Programs. (back to top)
2 For more, visit www.tcng.org/blog/post/browns-budget-reflects-need-to-invest-in-school-energy-efficiency. (back to top)
3 See U.S. Department of Energy’s (DOE’s) Buildings Technologies Program book, Guide to Operating and Maintaining EnergySmart Schools. (back to top)
4 Visit www.energyright.com/business/pdf/Schools_ESCD.pdf. (back to top)

Mark Bolton, IESNA, is regional sales manager at Gurnee, Illinois-based Kenall, which produces and supports lighting solutions for demanding environments. He has worked for lighting manufacturers for the past 34 years in numerous sales capacities, such as regional sales manager and regional vice president of sales. Bolton can be reached at mbolton@kenall.com.

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