This document discusses lighting efficiency and power density. It begins by asking about the differences between various lamp types from an energy efficiency perspective. It then discusses luminous flux, illuminance levels, and how to estimate the lighting power density for a house by counting lamps, determining lumens and recommended illuminance levels for rooms, and calculating watts per square meter. Finally, it outlines steps for determining the lighting power density for spaces by establishing illuminance levels, calculating lumens and watts, and verifying if the power density meets regulatory limits.

1. Instituto Tecnológico y de Estudios Superiores de Monterrey
Campus Querétaro
LIGHTING EFFICIENCY
Edification & Energy Efficiency
Prof. M. Arch. Susana García-San Román, LEED AP BD+C

2. LIGHTING BASIC CONCEPTS
What is the difference among:
•INCANDESCENT LAMPS
•FLUORESCENT TUBES
•FLUORESCENT COMPACT LAMPS (CFL)
•HALOGEN LAMPS
•LEDS (LIGHTING EMITTING DIODES)
from the point of view of energy efficiency?
What is the luminous efficacy of each type (lumens/watt)?

3. LIGHTING BASIC CONCEPTS
LUMINOUS FLUX (lumens) and ILLUMINANCE LEVEL (lux)

4. HOUSE HOLD LIGHTING POWER DENSITY
(watts/m2) ESTIMATION ACTIVITY
FOR YOUR HOUSE:
1- COUNT LAMPS AND MAKE A LIST SPECIFYING POWER (watts) OF EACH
ONE, ORGANIZED FOR EACH SPACE
2- DETERMINE LUMINOUS FLUX (lumens) OF EACH LAMP BASED ON ITS
EFFICACY
3- ESTIMATE ILLUMINANCE LEVEL (LUX) OF EACH ROOM BASED ON
SQUARE FOOTAGE (LUX = LUMEN / M2)
4- CHECK RECOMMENDATION BY IESNA:

5. HOUSE HOLD LIGHTING POWER DENSITY
(watts/m2) ESTIMATION ACTIVITY
FOR YOUR HOUSE:
5- ESTIMATE LIGHTING POWER DENSITY (LPD) FOR EACH ROOM
(watts/m2)
6- CHECK COMPLIANCE WITH RECOMMENDED LIMITS OF LPD (NMX-AA-
164-SCFI)

6. LIGHTING BASIC CONCEPTS

7. LIGHTING POWER DENSITY (watts/m2)
1- FOR ENERGY MODELING: INTERNAL HEAT GAINS
2- FOR ELECTRICAL BALANCE: PV ARRAY SIZING

8. LIGHTING POWER DENSITY (watts/m2)
STEP 1: DETERMINE ILLUMINANCE LEVEL IN EACH SPACE
(LUX) BASED ON IESNA (ILLUMINATION ENGINEERS
SOCIETY OF NORTHAMERICA) RECOMMENDATIONS FOR
DIFFERENT TASKS

9. LIGHTING POWER DENSITY (watts/m2)
STEP 2: DETERMINE LUMINOUS FLUX IN EACH SPACE
(Lumens) BASED ON SURFACE AREA OF EACH SPACE (lux x m2 = lm)
Space 1…
X m2
X lux
X lm
X watts
Space 2…
X m2
X lux
X lm
X watts

10. LIGHTING POWER DENSITY (watts/m2)
STEP 3: DETERMINE LIGHTING POWER IN EACH SPACE
(watts) BASED ON EFFICACY OF SELECTED LAMPS (lm/watt)
Space 1…
X m2
X lux
X lm
X watts
X watts/m2

11. LIGHTING POWER DENSITY (watts/m2)
STEP 4: ESTIMATE LIGHTING POWER DENSITY IN EACH
SPACE (watts/m2) AND VERIFY THAT THIS IS BELOW THE
LIMIT LPD ACCORDING TO THE MEXICAN NORM NMX-AA-
164-SCFI
Space 1…
LPD
X watts/m2