Recommendations by Sector
SCHOOLS
Energy Use
School buildings are ordinarily built to last a long time, but many older
schools are plagued with energy systems that waste energy, cause discomfort, and
are costly to maintain—or all three. Planning and executing a comprehensive
retrofit can frequently alleviate all three problems cost-effectively. Lighting
in many older schools constitutes 40% of the energy budget, followed by HVAC and
plug loads at approximately 25% apiece and hot water at 10%. After reducing such
internal loads as lighting, it may be possible to install smaller HVAC
equipment.
Many programs aimed at improving the energy efficiency and physical plants of
schools to enhance the educational environment are available. These range from
U.S. DOE’s Rebuild America/Energy Smart Schools Campaign and U.S. EPA’s ENERGY
STAR for Schools Program to the Sustainable Buildings Industry Council’s High
Performance School Building Program. The Consortium for Energy Efficiency
maintains a directory of these programs at www.cee1.org/com/bldgs/ees_dir.pdf.
Measures that are frequently found to be very cost-effective include the
following:
High-efficiency lighting
- Replace T-12 fluorescent fixtures with T- 8 or T-5 fixtures with
electronic ballasts.
- Use compact fluorescent lights (CFLs) to replace incandescents and save
energy and maintenance costs.
- Install and adjust automatic dimming controls to take advantage of
daylighting.
- Install and adjust occupancy controls in spaces used intermittently like
conference spaces, lounges, and storage rooms.
- Install LED exit signs.
- Upgrade parking lot lighting to save energy and reduce environmental
impacts.
- Educate janitorial staff, students, and teachers to minimize the use of
lighting.
Daylighting
- Consider retrofitting skylights in classrooms, gymnasiums, and media
centers. If combined with a roofing retrofit (which may also include enhanced
thermal insulation), the incremental cost of installing skylights may be
diminished. Install light control by louvers or diffusers to avoid glare.
Install and adjust automatic dimming controls to take advantage of
daylighting.
- Install light shelves one-third of the way down existing window walls to
direct light across the ceiling while shading lower glazing from direct beam
solar, thereby avoiding glare. Accompany this retrofit with a fresh coat of
semi-gloss white paint on the ceiling or install new light-reflective
acoustical tiles.
- If light shelves are impractical, take advantage of existing windows to
provide daylighting by using overhangs or other shading devices to keep direct
beam solar from causing glare.
- Design supplemental electric lighting systems to optimize daylighting by
specifying dimmable ballasts, photosensors, and daylighting controls. When
installed, photocell daylighting controls should be carefully calibrated and
tested. School building personnel should be trained in the use of this
technology.
- The “Cool Daylighting” approach helps to control for glare, achieves
better light distribution, and lowers cooling costs (see
www.daylighting.org/what_is_cool_daylighting.htm).
High-efficiency HVAC
- Consider a modern two-pipe retrofit, particularly if adding air
conditioning to previously un-air conditioned school buildings.
- Choose high-efficiency packaged A/C units listed by the Consortium for
Energy Efficiency in their Tier 2 guidelines (www.cee1.org/com/hecac/ac_tiers/impcttbl.htm).
- Downsize to a new high-efficiency chiller in conjunction with lighting and
other retrofits. Maintain chilled water temperature as high as practical.
- Consider using evaporative cooling.
- Use condensing boilers with large turn-down ratios whose efficiencies
improve with turn-down. Maintain hot water temperatures as low as practical.
- Switch over to direct digital controls (from hydraulic or manual
controls).
- Install variable air volume air handling systems with variable speed
drives.
- Install premium-efficiency motors.
- Install demand-controlled ventilation to ensure good indoor air quality
while minimizing energy use. This strategy is especially effective in
intermittently used spaces such as auditoriums and gymnasiums, but is also
useful in classrooms.
- Install energy-efficient unit ventilators with face and bypass controls.
- Upgrade the energy management system; optimize settings to reflect
building usage, weather patterns, and to shave peak electric loads.
- Verify economizer function and control.
- Consider using cool air from the cooling tower with water-cooled chillers.
- Consider indirect-direct evaporative cooling.
Other Measures
- Install high-quality, low-flow shower heads. Lower hot water system
temperature to 120 degrees.
- Insulate hot water lines wherever accessible.
- Replace chilled water drinking fountains.
- Install energy-efficient office equipment and use energy-saving features
like sleep modes.
- Use the duplex mode on copying machines to save energy and paper.
- Educate students about energy efficiency. Involve them in turning off
equipment and lights, and encourage their input in suggesting operational and
retrofit options for saving.
- Continuously commission buildings; educate maintenance staff to anticipate
as well as respond to energy-related problems.
- Install Vending Misers on vending machines.
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