ecologically responsible outdoor lighting - presented by bob parks, smart outdoor lighting alliance
TRANSCRIPT
Bob Parks, Executive Director
Smart Outdoor Lighting Alliance
www.SOLA.lighting
March 5, 2015
Anthropogenic or man-made
Artificial; not natural
Occurring during natural dark
cycle
Natural night brightness varies
due to moon phase cycle
(0.0001 - 0.3 lux at zenith)
WHAT IS LIGHT AT NIGHT?
18.7% of Earth’s surface is subject to artificial brightness of 10% or more above natural
61.8% of the United States
75% of US population lives under unnatural levels of LAN
LAN in major cities is typically 100 to 200 times brighter than a natural night sky
LIGHT AT NIGHT STATISTICS
LAN creates winners and losers
Attracts and repels
Disrupts:
Foraging
Predation
Migration
Reproduction
Communication
ECOLOGICAL IMPACT OF LAN
JP Stanley
Disruption of foraging patterns
Increases predation risk
Increases mortality on roads
Bats fly farther and use more
energy to avoid lights
Reduces body weight and
reproduction in females
MAMMALS
Disrupts natural cycles of
reproductive and migration
Birds fly into lighted buildings
Off-shore drilling platforms & towers
lighting causes significant attraction
Hydrocarbon flares attract and
incinerate night flying seabirds
BIRDS
Artificial light contributes to an
estimated
10 to 40 million
bird deaths annually in the
United States alone.
BIRDS
Jim Richardson
Diurnal (day) species extend activity
and exploit prey attracted to lights
Light attracts breeding frogs, who
stop calling
LAN has profound impacts on
physiology, behavior and
development
REPTILES & AMPHIBIANS
Reduces nesting habitat – Females avoid areas near lighted beaches
Hatching disorientation – Crawl towards area with brightest horizon
Which can often be roads or lighted development
Exhaustion/dehydration
Increases mortality
Increases predation
SEA TURTLES
Jelga
Fun Fact:
Great White sharks have now
learned to hunt seals at night
using city lights!
FISH
Most attracted to white light
Increases mortality at street lights
Confuses species that use light for communication (Fireflies)
Interferes with normal migration
Aquatic invertebrates – disrupts behavior and increases predation risk
INVERTEBRATES
PLANTS
Affects:
Germination
Leaf growth
Flower development
Fruit development
Leaf senescence
Abscission
Cessation of leaf production
Circadian Disruption
LAN disrupts immune system –
suppresses melatonin – affects all
species of animals and plants
Linked to insomnia, obesity, diabetes,
ADD, and cancer
Photo ganglion cells have peak
sensitivity ~480nm (Blue)
ECOLOGICAL IMPACT OF LAN
Jim Richardson
match and exceed older light sources over the next few years. Accordingly, LEDs have the
potential to meet many outdoor lighting requirements, including those utilizing advanced lighting
controls, variable brightness levels, precisely tailored light colors, shifting light colors and life
cycle cost. However, most LED installations so far ignore these potential features and instead
focus on a single metric – lumens per watt.
LEDs which emit in narrow spectral bands such as in the yellow (around 590 nanometers), for
example, have great potential to replace legacy LPS lighting systems long recommend for
protected zones around astronomical observatories if lighting is those areas is essential. Such
LED systems could also address concerns about protecting astronomical research, public
stargazing, and wildlife habitat.
Circadian Response
Artificial light sources have been shown to affect all living organisms through disruption of their
natural cycles that rely upon rhythms of daylight and night darkness. In humans, the peak
sensitivity of this response is in the range of 459-484 nanometers (blue).[4] [5]
The graph shows the visible spectrum, the human photopic sensitivity which defines the lumen, the
human circadian sensitivity and the typical output of a blue-rich white-light LED light source.
A large portion of light emitted by bluish-white LED source falls outside of the human photopic
vision range, but falls within the circadian sensitivity curve, where it does not aid photopic vision but
Broad Spectrum White Light
White LEDs start as blue
Highest CCD LED is the most
efficacious and have the most blue
spectral power distribution (SPD)
White light improves visibility
However, improvement in visibility
drops off above 3500K CCT
ECOLOGICAL IMPACT OF LAN
Broad Spectrum White Light
Efficacy vs. Ecological impact
As LED efficacy improves, compromise will become easier
Generally, use lowest CCD to minimize impact; however…
SPD & melanopic lux is best metric
Minimizing total lumens in the environment more important
ECOLOGICAL IMPACT OF LAN
LED SPECTRUM
5500 K CCT
LED SPECTRUM
2700 K CCT
Properly Shielded Fixtures
Direct light to the task area
Reduce skyglow and light trespass
Light for Visibility
Use just the illumination levels
necessary for the task
Eliminate glare
Reducing uniformity may improve
visibility by increasing contrast
BEST PRACTICES FOR ECOLOGICALLY
RESPONSIBLE OUTDOOR LIGHTING
Adaptive Controls:
Allows dimming to match pedestrian/vehicle
traffic illumination requirements
Employ timers/switches to turn off lighting
when no longer needed
Increase energy savings by 50% +
Reduce glare, energy costs and CO2
Increase fixture life
BEST PRACTICES FOR ECOLOGICALLY
RESPONSIBLE OUTDOOR LIGHTING
Tvilight
Tvilight
Spectrum
Narrow-band “true” amber and phosphor converted “PC” amber (~590nm) LEDs provide viable replacement for LPS
PC amber LED has greater efficacy 70-80 LPW than true amber LED at 35-40 LPW
“Turtle friendly” turns out to be best all around light source for ecologically sensitive areas
BEST PRACTICES FOR ECOLOGICALLY
RESPONSIBLE OUTDOOR LIGHTING
LED SPECTRUM
PC Amber
Dynamic Spectral Tuning
Arrays of different LEDs in fixture allow for
programming a variety of correlated color
temperature (CCT) over time
Locally or remotely controlled
Provide white light during peak activity hours
for maximum visibility; smooth transition
later to lower CCT
BEST PRACTICES FOR ECOLOGICALLY
RESPONSIBLE OUTDOOR LIGHTING
80% of outdoor lighting is used for Commercial & Public Exterior Lighting
~750 million Outdoor Lighting Fixtures* Worldwide
~160 million Outdoor Lighting Fixtures* in US
*Commercial & Public Exterior (Road, Street, Parking + Buildings)
WORLD OUTDOOR LIGHTING FACTS
Total Wasted Energy is approx. 60-70% overall from:
Unwarranted (not needed) = 25%
Over-lighting (excessive illumination) = 25%
Not dimmed or on curfew = 25%
Glare =15%
Uplight = 10%
WORLD OUTDOOR LIGHTING FACTS
Approx. Wasted Energy =
1.1 PetaWatt Hours Annually
The equivalent output of 500 power plants running 24/7/365
Could power ~ 7,750,000 homes
Producing 750 million tons of CO2
Cost = approximately $110 billion (US dollars)
WORLD OUTDOOR LIGHTING FACTS
