Lighting Efficiency
HEALTHCARE - TOP 5 GREEN BUILDING STRATEGIES
EPA Publication 909-F-07-001
What? People intuitively prefer natural light to artificial light. Daylight and optimized
artificial lighting can benefit hospital employees, patients and visitors. With rising
energy costs and climate change concerns, using energy efficiently is financially
prudent and expected. In addition, evidence suggests quantifiable benefits for
staff retention, patient healing, and customer satisfaction.
Why? Enhanced Community
Reputation:
Increases energy efficiency
and reduced climate impact
Improves building aesthetics
Demonstrates environmental
stewardship
Environmental /Staff/Patient
Benefit:
Improves indoor environment
for staff, patients, and visitors
Increases patient/staff satisfaction and comfort by providing more control of
indoor environment
Cost Competitive:
Improves facility's overall operational efficiency
Potentially reduces staff error rates, increases staff retention, and hastens
patient recovery
How? Use site selection and integrated building design
Maximize available natural lighting
Select lighting fixtures based on intended purpose
Optimize energy use with sensors, timers, and control features
Conduct audits to ensure continued effectiveness
Case Emory University
Studies ' University of Florida
Green Guide for Health Care (GGHC) Criteria: Construction: Energy & Atmosphere, Environmental Quality,
Operations: Energy Efficiency www.gghc.org
This is one of 5 Building Healthy Hospitals case studies developed by EPA's Pacific Southwest Regional Office,
with Resource Conservation Challenge and Pollution Prevention funds.
www.epa.qov/reqion09/waste/p2/pro1ects/hospart.html
Indoor Air Sustainable Flooring Process Water Efficiency Lighting Efficiency Energy Efficiency
Building Healthy Hospitals 1
This fact sheet was produced by EPA's Pacific Southwest Regional Office. Mention of trade names, products, or services does not
convey, and should not be interpreted as conveying official EPA approval, endorsement, or recommendation.
Printed on 100% recycled paper, 50% post-consumer content - process chlorine-free
2007
':
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Lighting Efficiency
HEALTHCARE - TOP 5 GREEN BUILDING STRATEGIES
CASE STUDY: DECREASED LIGHTING POWER DENSITY, EFFICIENT FIXTURES,
AND OCCUPANCY SENSORS
Applicability:
Environmental
Impact:
Other Benefits:
New construction, major renovation, or remodeling
projects.
Winship Cancer Center: 31% savings in lighting
energy
University of Florida: Lighting energy
consumption/savings not monitored
No other potential benefits such as worker satisfaction
or productivity or patient outcome are monitored by
either Emory or Univ. of Florida
Background
Improving lighting efficiency can be an inexpensive and effective way to
achieve LEED Energy & Atmosphere credits. All of the case study facilities
used strategies for maximizing natural lighting and minimizing artificial
lighting. Emory implemented several strategies to improve lighting
efficiency, including:
- Incorporate Natural Lighting Features into Design. Strategic
building siting and orientation, skylights, large and strategically-placed
windows, and locating high-use rooms in parts of the building with the most
potential for natural light all can maximize daylighting.
Decreased lighting power density. Lighting power density is expressed in watts
per square foot for a given occupancy and individual space; maximum allowable
lighting density is defined by ASHRAE 90.1. Energy use can be minimized by
designing spaces that require a lighting power density less than the allowed
maximum while still providing adequate light to meet occupant needs and visual
comfort.
Efficient lighting fixtures. Similar to varying efficiency of light bulbs, lighting
fixtures are available with a variety of technologies that impact their overall
efficiency. Fixture efficiency is simply the amount of light leaving a fixture compared
to the amount of light generated by a given light source within the fixture. Energy
use is directly impacted by the efficiency of fixtures installed throughout a facility.
Use of occupancy sensors. Occupancy sensors control lighting based on the
presences or absences of motion or heat. Occupancy sensors reduce energy use by
automatically turning-off lighting when a space is unoccupied.
Building Healthy Hospitals
An EPA Region 9 P2 Project
2007
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Lighting Efficiency
HEALTHCARE - TOP 5 GREEN BUILDING STRATEGIES
Performance
None of the case study facilities monitored lighting energy use separately from other energy
use in their building. Based on energy use modeling conducted during the LEED certification
process, and using the strategies above, Emory estimates its reduced energy consumption
by 31 percent for compared to a similar facility (see Exhibit). Specific strategies Emory
used at the Winship Cancer Institute are as follows:
Emory decreased lighting densities throughout building from 1.6 watts per square
foot (baseline case facility) to 1.1 watts per square foot. Emory University did not
reduce the number of lighting fixtures installed through the facility.
High-efficiency lighting fixtures were installed throughout the Winship Cancer
Institute. Emory uses T-8s throughout campus; they do not use T-12s and have
considered T-5s, but their electrical engineer does not believe the cost/benefit is
sufficiently attractive; very few incandescent light bulbs are typically only used for
dimming; compact fluorescents are use in can lights.
Infrared occupancy sensors were installed to control lighting, in offices, laboratories
and non-clinical spaces. The sensors detect both heat and motion and include a 15-
minute timer with override controls. Emory University installed wall mounted
sensors in offices and small occupied spaces and ceiling-mounted sensors in
hallways, large classrooms and bathrooms. Emory estimates that the sensor alone
can decrease lighting energy use 10 to 25 percent depending on the location.
Specific strategies used at the University of Florida Orthopedic Center:
Installation of high-efficiency lighting fixtures, mainly fluorescents (CFLs and T-8
bulbs) throughout the facility along with a very limited number of other less efficient
bulbs used for specialty tasks.
Lutron brand occupancy sensors were installed throughout areas of the building with
lower occupancy including patient rooms, hallways, and offices. The University of
Florida building maintenance staff indicated the need for additional ongoing
maintenance effort from adjustments required by building occupants. In addition to
the initial adjustments made immediately after installation, staff turnover and
equipment "calibration" required a sustained maintenance effort.
Cost
Emory stated that the initial lighting cost for the Winship Cancer Center was less
than 10 percent higher than other similar facilities with conventional lighting systems
and that the estimated payback was less than 2 years.
Building Healthy Hospitals 200?
An EPA Region 9 P2 Project 3
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Lighting Efficiency
HEALTHCARE - TOP 5 GREEN BUILDING STRATEGIES
Generally, occupancy sensor costs depend on the type and function of the sensor
and range from $20 to $100 each. Watts Stoper, Novatos, Lutron SensorSwitch are
common brands offering occupancy sensors.
[4~U4~iĞ- Case Study Vitals
The following summarize success criteria for implementing this project at other healthcare
facilities:
Gather input from building occupants prior to designing artificial lighting systems,
particularly when installing sensors in patient care areas and incorporate comments
into implementation.
Educate building occupants about the lighting efficiency features of the building to
gain acceptance and reduce maintenance/adjustment. Consider using stickers,
signs, and regularly updated energy consumption reporting to inform and encourage
continued support and compliance.
Track and record any labor savings associated with less frequent lamp changeout
(e.g., from longer lasting fluorescent and LED lamps) to help justify initial cost
premiums of high efficiency equipment.
The sensitivity of occupancy sensors should be appropriate for room size and relative
occupancy. There are two primary sensing technologies: passive infrared and
ultrasonic that are suited to different applications (see the following description for
further explanation:
httD://www.lutron.com/Droducts/OccSensors.asDx?Did = PIRUSDT&cid=0
Building Healthy Hospitals 200?
An EPA Region 9 P2 Project 4
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Lighting Efficiency
HEALTHCARE - TOP 5 GREEN BUILDING STRATEGIES
USGBC LEED CALCULATOR 2.0 - EMORY WINSHIP CANCER CENTER
EA4 Results.xls
EA Prerequisite 2 / EA Credit 1 / EA Credit 2
ECB Table
Energy Summary by End Use
Proposed Building
End Use Energy Type
Energy
Lighting - Conditioned
Space Heating
Space Heating
Space Cooling
Pumps
Tower
Fans
Electricity
Gas
Electricity
Electricity
Electricity
Electricity
Electricity
Service Water Heating Gas
Equipment
Energy and Cost
^^^H
Type
Electricity
Natural Gas
Process Energy*
Total Nonrene'vV.rible
Electricity
TOTAL BUILDING CONSUMPTION
Summary by Fuel Type
DEC1 Use
[103Btu/hrl
22,253.057 $
57,731,562 $
(2.844,042) $
77,140.577
no' Btu/hi
2,866,353
57.527.451
786.875
6.897.085
1.059.853
1.528,590
6.270,260
204,111
2.844,042
79,984,619.1
DEC1 Cost
r$i
326,106
279,812
(41,677)
564,241
Budget Building
Energy
[10sBtu'hl
4,131,598
57,062.680
760,924
11.921,538
1.758.030
2.914.732
6.270,260
204,111
2,844.042
87,867.913.2
ECB' Use
[103 Btu/hrl
30,601.123
57,266.791
(2.844.042)
85.023.871
Optimized 1
Energy 1
Performance 1
[%] 1
69%
101%
103%
58%
60%
52%
100%
1 00%
100%
ECB' Cost
F$l
$ 448.441
$ 277,559
$ (41.677)
684,323
91%
DEC' / ECB1
Energy % Cost %
73% 73%
101% 101%
100% 100%,
Renewable
Total including Renewable 154.281,154 $
564,241
170.047.743
$ 684,323
Percent Savings = (ECB' $ -DEC1 $)/ECB' $ = 17.55%
* Cost calculated using virtual rate ($/kWh) computed by Visual DOE
Building Healthy Hospitals
An EPA Region 9 P2 Project
2007
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