Lighting Design:
Energy Efficient Lighting Design:
Ways to Make the Right Choices
Sanford Lighting Design
Palo Alto, CA
1
How do you decide how to light your space?
• Assess how much general light you need for the space
• Consider visual tasks and where you need light
• Determine what highlighting and other lighting techniques you can
use to enhance the space
• Compare energy efficiencies and choose a source
• Choose a color temperature and confirm the color rendering index
• Consider where the light is going and choose an appropriate fixture
type
• Select the right auxiliary devices, if needed, for the lighting fixtures
you are using
2
Energy Efficiency Terms
Lumens
Output is the measure luminous flux (F) - the total amount
of light energy emitted from a source.
It is expressed in lumens.
Wattage
Power is measured in watts (W) - the rate at which energy is used.
Efficacy = lumens per watt
Efficacy is lighting efficiency, measured in amount of output in
lumens per watt.
Use of Electrical Power
1000W = 1kW
Energy use is measured in
amount of power used over
time.
Measured in Whrs (Watthours) or in kWhrs
Light Efficiency (efficacy)
The values of
lumens or lumens
per watt (lpw) are
often displayed on a
package.
Like gas mileage, the
measurement of
light efficacy is
similar to miles per
gallon. The higher
the number the
more efficient the
light source.
Standard
incandescent
A-lamp
LED
960 lumens/8W
= 120 lpw
1190 lumens/75W
= 15.8 lpw
Luminous Flux
Sample list of average lumens for traditional sources
32 W
Comparisons
13 lpw
18.6 lpw
65 lpw
72.2 lpw
White light – Color Temperature
C C T – Correlated color temperature is the color of a light expressed in degrees K.
Light sources that are called “white” can have a range of
color temperatures.
In residences, they usually are between 2700K and 4000K.
Color temperature
Many sources, such as CFLs and LEDs come in
a variety of colors.
Color rendering index (CRI)
The Color Rendering Index (CRI) measures how well
colors are rendered compared to a reference light
source on a comparative scale, from 0 –100.
By definition, daylight has a CRI of 100.
At lower brightnesses, the incandescent and halogen sources by
definition have a CRI of 100.
The CRI is critical for distinguishing color, or when you want to show skin
tones accurately.
California’s Title 24
Compliance

Minimum efficacy is
established

CRI must be 90 or higher

CCT of 2700K to 4000K
What do you want to light?
Step 1 - Consider your general lighting
Lighting a vertical surface
gives a sense of brightness
Recessed downlighting is often
the most basic lighting technique
Step 2
Apply high-impact
techniques:
Accent
Wall-washing
Niches and shelves
Grazing
Uplighting
Patterns
Exterior views
Randall Whitehead
13
Apply high-impact
techniques:
Accent
14
Apply high-impact
techniques:
Wall-washing
Chanel Encore
2010 IALD Award Winner,
Fisher Marantz, Stone
Las Vegas, 15
NV
Apply high-impact
techniques:
Grazing
Grazing exaggerates texture.
16
Apply high-impact
techniques:
Wall-washing vs grazing
17
Apply high-impact
techniques:
Niches and shelves
From above, point source
From above, linear source
Apply high-impact
techniques:
Niches and shelves
From below,
linear source
From above and below,
to light glass
Apply high-impact
techniques:
Niches and shelves
From above,
point sources too
spread out
Apply high-impact
techniques:
Uplighting
21
Apply high-impact
techniques:
Patterns
Pattern based on
beam layout
Pattern roughly
along cabinets
22
Apply high-impact techniques:
Exterior views
Creates a larger
visual space
23
How Much Light Do You Need?
Depends on room size, ceiling height, reflectances of
surfaces, quantities of fixtures
Light Sources are tending
towards LEDs
Incandescents, including halogens, produce
light with a glowing filament. They have
excellent color, short lives, and use energy to
generate heat, making them inefficient light
sources.
Light Sources are tending
towards LEDs
Fluorescents and compact fluorescents (CFLs) have electrodes that
generate a high voltage to create a mercury vapor, and emit ultraviolet
light.
The ultraviolet light strikes a phosphorescent coating on the inside of the
bulb and causes it to glow with visible light.
Benefits:
Low cost
High efficacy
Long life.
Color emitted from the lamp:
From mixture of phosphors
On the inside of the lamp.
Light Sources are tending
towards LEDs
LEDs (light emitting diodes)
generate light by passing
current over an diode, a
two terminal electronic
component that looks like a
tiny metal plate.
They are extremely
compact and durable with a
50,000 – 100,000 hour life
or longer.
White and Colored LEDs
New developments produced a white LED
with the inclusion of a phosphorescent
inner coating, similar to a fluorescent
lamp.
These are sometimes referred to as
phosphor based white LEDs.
There are white LEDs, RGB (red, green,
blue) LEDs, RGBW (red, green, blue,
white) LEDs and RGBWA (includes
amber) LEDS.
All have increasing lpw values, improving
output and controls.
LED
As an alternative to multitudes of small LEDs,
lamps were developed with much larger LED
modules.
Known as high power LED (HPLED) they greatly
increase the amount of emitted light but
introduce a major heat issue.
Diodes are very sensitive to heat and will fail in
seconds if too hot.
This problem is solved a number of ways; heat
sinks, heat distribution fins and even tiny fans.
All this technology increases the cost of each
lamp.
LEDs need drivers
LEDs require drivers to
operate.
They take an incoming
alternating voltage
(usually a range, and
should include 120V)
and change it to a
constant current lower
voltage the LEDs need.
(usually 12V or 24V)
LEDs need drivers
Drivers are often alongside the fixture, provided as
part of the installation.
LEDs need drivers
Most dedicated LED fixtures will state the
characteristics of the integrated LED driver.
Lighting Design – what do
you need to do?
Think about your specific application,
and
Consider the
output
Consider the
color
Consider the
distribution
Making Fixture Choices
Replacement lamps
Uses existing fixtures and lamp
bases
Making Fixture Choices
Recessed downlight trims
that include the LEDs can
replace existing trims and
keep existing housing.
Fixture locations remain
the same.
Choose appropriate
aperture (opening) size,
fixed or adjustable, output,
color, beam spread, trim
Making Fixture Choices- Recessed downlights
New lighting locations, new fixtures and IC (insulated ceiling) rating for
residential
Making Fixture Choices - Sconces
Glare could be
an issue
Making Fixture Choices – Linear lights
Making Fixture Choices – Linear lights
Under cabinet lights make the
cabinet look like it’s floating
Making Fixture Choices
Undercabinet tasks
Hide fixtures under cabinets
where tasks take place.
Controls
Drivers are usually dimmable. Each driver type must be compatible with the
dimmer type on the wall or the automated control system.
It is important to check the dimming protocol for each dimmable driver.
Often a replacement LED lamp or recessed trim assumes the input will be
from an incandescent residential dimmer. But some companies have
products that work with a variety of sources and drivers.
Controls – Protocols for
dimming LED drivers
Compatibility
Technical paper
1000.bulbs
Thank you!
Questions?