lighting by linxiaoqin


									                                         NSF/IUCRC Center for Building performance and Diagnostics at Carnegie Mellon University
                                                          Advanced Building Systems Integration Consortium
                                                          Guidelines for High Performance Buildings 2004

              Replace outdated office lighting with quality lighting components featuring
                   high-performance lamps, ballasts, fixture and advanced controls
                  for 27 - 87% lighting energy savings, 0.7 - 26 % productivity gains,
                           and 27% headache reduction, with ROIs over 236%

Lighting systems in office buildings must be carefully designed for high lighting quality and energy conservation. Good office lighting requires
an adequate amount of light for variations in the types of work, distribution that supports dynamic space planning, balanced brightness-
contrast, good color rendition, user adjustability, and daylight and/or occupancy responsive dimming. Lighting quality is an essential part of
the quality of office working environment, contributing to long-term job performance and occupant health.

                                           Outdated practice ( minus 2-point solution)                                               Best practice ( 9-point solution)
                                           (lighting energy intensity > 2 W per square foot)                                         (Split task + ambient lighting <1 W per square foot)
Lamp                                       T-12 fluorescent or incandescent lamps                                                    T-8/T-5 fluorescent lamp or CFL lamp
Ballast                                    Magnetic or hybrid ballasts                                                               Electronic ballasts
Lens                                       Flush/K-12 prismatic lens                                                                 Lens to avoid direct and reflected glare
Fixture                                    Direct lighting fixture                                                                   Indirect lighting fixture for ambient light
                                           No reflectors, or large cell parabolic louvers                                            High performance reflector matched to lamp
Controls                                   Floor by floor “blanket” control                                                          Daylight dimming on ambient light,
                                           On-off switch only                                                                        User dimming and occupancy sensor on task light

Task light                                 Fixed underbin lights                                                                     Relocatable task light with articulated arm
                                           (often provided due to shadowing problems)                                                or relocatable ceiling based task-ambient light

High performance lighting pays!
Twenty-five studies have shown that high performance
lighting systems can pay for themselves in less than                                                           Costs and Benefits of High Performance Electric Lighting Systems
one year due to energy, productivity and health                                                       $1,800                                                                 $1,600
benefits.                                                                                                                                                                  productivity
CMU’s BIDSTM demonstrates that high performance                                                       $1,400
lighting yields annual total energy cost savings of $82
                                                                               Dollars per Employee

per employee ($0.41 per square foot), annual                                                          $1,200
productivity gains of $1,600 per employee, and annual
health cost savings of $20 per employee, for total                                                                 $720
savings of up to $1,702 per employee annually*.                                                        $800        retrofit

With a median first cost of $720 per employee for                                                      $600
lighting retrofits ($3.60 per square foot, range $0.63 -                                               $400                        $200
$7.45), and a median first cost increase of $200 per                                                                          new construction                     $82
employee for high performance lighting systems in                                                      $200                                                       energy                   $35
new construction ($1 per square foot, range $0.26 -                                                                                                                                       health
$10.65), an investment in high performance electric
lighting results in an ROI of 236% for retrofits and                                                            ONE-TIME first cost                                   ANNUAL benefits
851% for new construction!

*Using BIDSTM baseline assumptions (national averages)
                                NSF/IUCRC Center for Building performance and Diagnostics at Carnegie Mellon University
                                                 Advanced Building Systems Integration Consortium
                                                 Guidelines for High Performance Buildings 2004

Recommended High Performance Electric Lighting for Open Plan Office Setting
        T-8 / T-5 / CFL fluorescent lamp
        Electronic ballast (except CFL lamp)

Points: (Recommended to achieve greater than 5 points)
    SYSTEM                                            FIXTURE                                                        CONTROL                     TASK LIGHT

                                            Indirect/direct lighting fixture                            Daylight dimming on ambient light    Relocatable task light
      Split                                                    (2 points)                               (1 point)                            with articulated arm
 Task + ambient                                                                                         User dimming control on task light   or relocatable ceiling-
     system                                                                                             (1 point )                           based task light (1
 (ambient <30fc)                                                                                        Occupancy sensor on task light       point)
                     Medium cell parabolic louver           High performance reflector in fixture       (1 point)
   (2 points)
                     (1 point)                              matched to lamp (1 point)

                                            Indirect/direct lighting fixture                            Daylight-responsive dimming on       Ambient lighting
    Combined                                                   (2 points)                               overhead lighting                    fixture relocatable
Task and ambient                                                                                        or individual dimming control        according to user
     system                             High performance reflector             Lighting fixture 100%    (1 point)                            needs (1 point)
(>50fc throughout)   Medium cell        in fixture matched to lamp             aligned w/ workstation
    (0 point)        parabolic louver   (1 point)                              (1 point)
                     (1 point)

Benefits of High Performance Electric Lighting Systems
CMU’s BIDSTM has identified 15 case studies linking improved lighting design with a median of 60% savings in annual lighting energy worth
approximately $80 per employee per year.
                            NSF/IUCRC Center for Building performance and Diagnostics at Carnegie Mellon University
                                             Advanced Building Systems Integration Consortium
                                             Guidelines for High Performance Buildings 2004

Six case studies identify a link between improved lighting design and total annual energy savings, including reductions in lighting, cooling
and other HVAC energy consumption, with a median savings of 18% or $82 per employee per year. The average lighting energy savings is
4.9 KWh per square foot annually, and the additional cooling energy savings averages 0.2 KWh per square foot per year.

Nine case studies identify a link between improved lighting design and individual productivity gains, with a median improvement of 3.2%
or $1,600 per employee per year. Productivity is evaluated by a range of measured including improved working speed, reduced error rate,
improved reading comprehension, improved short-term memory and logical reasoning, or self-reported increases in productivity.

Finally, a 1988 controlled experiment by Aaras et al identifies a link between improved lighting design and a 27% reduction in the incidence
of headaches, which accounts for 0.7% of overall employee health insurance cost at approximately $35 per employee annually.
                          NSF/IUCRC Center for Building performance and Diagnostics at Carnegie Mellon University
                                           Advanced Building Systems Integration Consortium
                                           Guidelines for High Performance Buildings 2004

BIDS TM Case Study Examples of High Performance Lighting Systems
                              Reynolds Metals / Energy User News 2001
                              In a 2001 case study of the Reynolds Metals Company office in Richmond, VA, Energy User News identifies an
                              87% reduction in lighting energy consumption following a replacement of T-12 lamps and magnetic ballasts with
                              Ledalite’s ErgolightTM intelligent lighting system. The ErgolightTM system features suspended direct/indirect (70/30)
                              fixtures aligned to each workstation, with personal dimming, occupancy sensing, daylight-responsive dimming and
                              centralized network control.

   Building case study         Reynolds Saves Over 85% in Energy Costs, Improves Lighting Quality. (2001) Energy User News 26:2, pp. 26-
                              27; Audin, Lindsay (2001) A brainy luminaire for the 21st century, Architectural Record 189:11, pp. 208

                              Shavit and Wruck 1993 | CBPD/Steffy 1999
                              In a 1993 simulation study in 3 climates, Chicago, Washington, DC, and New Orleans, Shavit and Wruck identify
                              an average of 36.4% total energy savings, including cooling and associated HVAC cost savings, by introducing a
                              high-efficiency lighting system that uses dimmable electronic ballasts and incorporates four control strategies
                              (scheduling, lumen maintenance, daylighting, and fine-tuning), as compared to a base-case building with a
                              conventional lighting system.

                               Shavit, G., and Wruck, R. (1993) Energy Conservation and Control Strategies for Integrated Lighting and HVAC
    Simulation study          Systems. ASHRAE Transactions, Vol. 99, pp. 1; CBPD / Gary Steffy Lighting (1999) Life Cycle comparisons of
                              Direct and Indirect Lighting for Offices - Draft Research Report. Center for Building Performance and Diagnostics
                              (CBPD), Carnegie Mellon University, Pittsburgh, PA.

                              PP&L / Romm and Browning 1994
                              In a 1994 before and after building case study of the Pennsylvania Power and Light (PP&L) drafting office in
                              Allentown, PA, Romm and Browning identify a 13.2% increase in productivity, a 25% reduction in absenteeism
                              and 69% lighting energy savings following a lighting retrofit introducing high-efficiency ballasts, T-8 fluorescent
                              lamps and parabolic louver fixtures. The new lighting system was designed especially to reduce direct and
                              indirect glare. As a result, the time required for an engineer to complete one drawing decreased from 6.93 hours,
                              or 0.144 drawings per hour, to 6.15 hours, or 0.163 drawings per hour— a 13.2% increase in productivity. In
                              addition, the use of sick leave among engineers declined 25%, from 72 hours per year to 54 hours per year.

                              Romm, J.J., and W.D. Browning (1994). Greening the Building and the Bottom Line - Increasing Productivity
   Building case study        Through Energy-Efficient Design. Rocky Mountain Institute

                              Aaras et al 1998
                              In a 1998 controlled experiment, Aaras et al identify a 27% reduction in the frequency of headaches in computer
                              workers when conventional downlighting is replaced by user-controlled suspended direct - indirect lighting (75/25)
                              and venetian blinds are added to windows.

                               Aaras, A., Horgen, G., Bjorset, H., Ro, O., and Thorsen, M. (1998) Musculoskeletal, Visual and Psychosocial
  Controlled experiment       Stress in VDU Operators Before and After Multidisciplinary Ergonomic Interventions. Applied Ergonomics, pp.
                                      NSF/IUCRC Center for Building performance and Diagnostics at Carnegie Mellon University
                                                       Advanced Building Systems Integration Consortium
                                                       Guidelines for High Performance Buildings 2004

Energy Conservation
With a total area of 12 billion square feet, U.S. office buildings use over 86 billion kWh for lighting each year. Almost half of office buildings
are using outdated lighting systems with T-12 fluorescent lamps and magnetic ballasts. At the 2003 U.S. average energy cost of $0.08 per
kWh, the potential savings from implementing good practice high performance lighting systems (5-6 points) in 50% of office buildings is more
than $2.1 billion each year. Over 25.8 billion kWh would be saved annually—an amount of energy equal to:

 One-third the annual
 energy production of the
 Three Gorges Dam

 6.5 times the annual
 energy production of the
 Hoover Dam

 The annual energy use of
 955,000 U.S. households
 ( = 10,000 houses)

 The gasoline used by
 1,288,000 cars in a year
 (    = 10,000 cars)

Energy - Associated Benefits
The annual energy savings of 25.8 billion kWh achieved by implementing high performance electric lighting systems in 50% of U.S. office
buildings would generate valuable reduction in emissions and water consumption due to power generation, for a total additional savings of
$897.2 million annually, and one-time peak load reduction with a value of $6.98 billion.

                 Peak Load Reduction                                             Emissions Reductions                  Water Consumption Reduction
                                                                                 Annual              Annual
                                                                     Pollutant   reduction           cost savings
                                                                     CO2         36.1 billion lbs    $249.3 million       51.6 billion gallons / year
                       5,820 MW
                                                                                                                          with an estimated value of
               with an estimated value of
                                                                     SO2         156.7 million lbs   $374.7 million        $103.2 million annually
                      $6.98 billion
             (average 48.5% peak load reduction)                     NOX         76.7 million lbs    $262.9 million

                                                                     PM10        3.3 million lbs     $7.5 million

Productivity and Health Benefits
Given the average productivity and health benefits of $1,600 and $35 per employee, respectively, the total savings achieved by providing
high performance electric lighting to 50% of U.S. workforce is $49.1 billion annually.

All references and assumptions for these data are available online

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