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Opportunities to save energy exist in all aspects of government operations, from building construction and lighting to large-scale transportation activities. The following case studies describe some of the energy management initiatives adopted in other cities and counties in the United States. For more information on how to save energy, see energy efficiency.

San Diego County, California:
Energy efficient lighting and a mechanical upgrade

The City and County of Denver, Colorado:
LED traffic signals

Housing Authority, Chicago, Illinois:
ENERGY STAR® volume purchases

Montgomery County, Maryland:
Resource conservation program

City Hall, Ann Arbor, Michigan:
Natural gas-powered chiller

City of Bowling Green, Ohio:
Green lights program

Frank J. Lausche State Office Building, Cleveland, Ohio:
Comprehensive energy management program

City of Portland, Oregon:
City energy challenge program

Department of Natural Resources, Salt Lake City, Utah:
The "whole-building" approach


Energy-efficient lighting and a mechanical upgrade

As part of the ENERGY STAR Buildings and Green Lights Partnership, leaving NYCWasteLess San Diego County, California leaving NYCWasteLess installed energy-efficient lighting in 95 percent of its 5 million square feet of building space. Fluorescent lights replaced incandescent lights, and more efficient T8 fluorescent lamps took the place of existing T12 lamps. Exit signs were also retrofitted with LEDs (light-emitting diodes). The lighting project cost $1.4 million at 82 percent completion, with annual cost savings of more than $1.12 million.

During the lighting upgrade, the County's energy management team designed a mechanical upgrade for a nine-facility government complex, replacing chillers and fan system motors. The building upgrades saved San Diego money and addressed concerns about CFC phase-outs. Since the upgrades, the County's electric bills have stabilized at $9.5 million per year.

See building improvements for more information on increasing energy efficiency through building upgrades.

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LED traffic signals

As part of the International Council for Local Environmental Initiative's (ICLEI) leaving NYCWasteLess Cities for Climate Protection program, the City and County of Denver leaving NYCWasteLess replaced traditional incandescent bulb traffic and pedestrian signals with LED (light-emitting diode) signals. LED signals use less electricity than traditional traffic signals and have a longer life expectancy, dramatically reducing maintenance and replacement costs.

The City and County of Denver replaced approximately 30,000 traffic signals with LEDs. Each installation replaces a 150-watt or 69-watt incandescent bulb with LEDs requiring only 14 or 8 watts of electricity respectively. The project initially focused on red and orange lights, and then moved on to green lights once advances in LED technology made this color available and affordable. The LED signals have a payback period of less than four years and the total cost savings over the lifetime of the fixtures is estimated to be more than $6.1 million.

Denver also installed nearly 90,000 square feet of low-E (low-emittance) window film on glass in more than 1.4 million square feet of floor space.

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ENERGY STAR® volume purchases

The U.S. Department of Energy leaving NYCWasteLess works with partners, such as the Consortium for Energy Efficiency, leaving NYCWasteLess to organize buyer groups to purchase large quantities of efficient appliances, lowering manufacturers' and buyers' costs and speeding market introduction of efficient appliances. Through this national initiative, public housing agencies and utility companies in Chicago and 37 other cities purchased at least 71,000 Magic Chef brand refrigerators, produced by Maytag. leaving NYCWasteLess The refrigerators use compressor technology developed by the U.S. Department of Energy. These refrigerators saved an estimated $4.04 million in electricity costs annually for housing agencies and low-income consumers across the country. The DOE also develops procurement specifications for the volume purchases and validates the energy savings.

The Chicago Housing Authority leaving NYCWasteLess in Illinois purchased 10,000 Magic Chef brand refrigerators, which reduced annual electric bills by more than $500,000.

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Resource conservation program

Montgomery County, Maryland leaving NYCWasteLess has become a national leader in the field of commissioning buildings, recognizing the need to continually refine facility operations and systems. For new construction, the County meets an aggressive goal of saving 40 percent of the energy used in a typical new facility. As a participant in the Green Lights Program, now part of Energy Star, leaving NYCWasteLess the County also placed considerable emphasis on retrofitting existing facilities. The County converted lighting in all facilities to new technology lamps, ballasts, and controls. As a result of these retrofits, Montgomery County anticipates $5 million in cumulative energy cost savings.

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Natural gas-powered chiller

In Michigan, Ann Arbor City Hall leaving NYCWasteLess replaced an obsolete 200-ton, electric-powered chiller with a new, 150-ton gas-powered chiller to provide air conditioning for the 90,000-square-foot building. After the energy utility's incentive rebate of $35,000, the cost to install the chiller came to $156,000. The installation of the new chiller reversed the trend of increasing electric costs, leading to average annual savings of $28,000 per year. Ann Arbor realized additional electric bill savings through lighting retrofits and a building energy management system.

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Green lights program

In 1993, the City of Bowling Green, Ohio leaving NYCWasteLess joined the U.S. Environmental Protection Agency's Green Lights Program and launched an initiative to upgrade its lighting systems. (The Green Lights Program, now part of Energy Star, leaving NYCWasteLess aims to prevent pollution by encouraging U.S. institutions to use energy-efficient lighting technologies.)

The City of Bowling Green replaced 300 old fixtures in the city administration building with energy-efficient lamps, reflectors, and electronic ballasts. Fluorescent "EXIT" signs replaced incandescent signs, and the city installed occupancy sensors to switch off unneeded lights. These changes resulted in a 50 percent reduction in electricity use for lighting, saving more than $4,000 per year, achieving payback in 1.8 years.

The city also replaced pedestrian and traffic signal lamps with fiber optic and LED (light-emitting diode) lamps. These changes resulted in a 69 percent reduction in electrical usage and savings of more than $350 annually. The low-wattage LED lamps will last for at least 10 years, or 10 times longer than the old incandescent ones.

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Comprehensive energy management program

Through the implementation of a comprehensive energy management program, the Frank J. Lausche State Office Building in downtown Cleveland, Ohio, reduced its electric bill by $90,000 per year. Components of the program included retrofitting the building's lighting system with new lamps and ballasts, installing lighting motion sensors in restrooms, retrofitting the heating, ventilation, and air conditioning (HVAC) controls, weatherizing the building shell, rebuilding the domestic water and fire pumps, and replacing entry door seals.

The U.S. Environmental Protection Agency leaving NYCWasteLess includes the Frank J. Lausche State Office Building in its registry of ENERGY STAR Labeled Buildings. leaving NYCWasteLess This registry lists the top 25 percent of energy-efficient buildings in the nation.

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City energy challenge program

Through the City Energy Challenge leaving NYCWasteLess program, the City of Portland, Oregon, leaving NYCWasteLess identified more than $1.3 million in annual energy savings for city government facilities, and completed projects that saved $1.1 million. In municipally owned buildings, the City of Portland promotes cost-effective energy savings (simple paybacks of ten years or less) and takes advantage of utility, state, and federal technical and financial assistance programs.

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The "whole-building" approach

When the Utah Department of Natural Resources leaving NYCWasteLess designed and built its new office building in Salt Lake City, it incorporated a "whole-building" approach to ensure that the entire building worked as a single system to reduce energy consumption. The improved design reduces energy use by 42 percent compared to similarly sized buildings.

The building's orientation minimizes solar heat gain and maximizes natural light. Light shelves shade the building from glare and heat while reflecting natural light into the building. Strategically placed windows with coated glass admit sunlight while blocking harmful and heat-producing rays. High-efficiency ceiling and task lighting supplement natural lighting. LED signs, occupancy sensors, and dimmers further reduce energy consumption. Innovative evaporative cooling technology reduces the need to use mechanical chillers. The cooling and air exchange systems operate using high-efficiency motors and variable speed drives, which saves energy. The building's landscaping also maximizes energy efficiency.

For more information on whole-building design, see resources, or visit the Whole Building Design Guide, leaving NYCWasteLess and High Performance Building Research. leaving NYCWasteLess

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