LED Lighting: A new notion in the field of
Illumination
Shital Kumar Gupta
Research Assistant
Dept. of Electrical & Electronics Engineering
Kathmandu University
Description of the Project
Solar and WLED for Greener and Brighter Nepal
Project Owner: Kathmandu University
Project Duration: Two Years
Partner Organization: Altitude Innovation Pvt. Ltd.
Project Team Members:
Project Leader: Diwakar Bista, Assistant Professor, KU.
Activity Leader: Sudan Basnet, Director, Altitude Innovation Pvt. Ltd.
Researchers: Shital Kumar Gupta & Dipendra Mandal
– As stated by World Bank, at the start of the 21st century, there are more
people without electricity than at the end of the 19th century and this rate
will increase due to increment in population and energy crisis
– Most common end use of electricity is for illumination
– Large majority of population from developing countries are not grid
connected and rely on fossil fuel for illumination
– Due to energy crisis and frequent load shedding people from urban areas
are also forced to find and alternative source for illumination
– Present scenario demands efficient, cost effective and reliable source for
illumination
LED lighting: A new notion in the field of Illumination
• Light Emitting Diode (LED)
– Semiconductor device capable of producing light
– Characteristic similar to other diode but are capable of emitting optical
radiation when exited by electrical field
– Available in different color and its emission spectrum is determined by
semiconductor material used
– LED emitting white light is referred as White Light Emitting Diode (WLED)
LED lighting: A new notion in the field of Illumination
• Light Emitting Diode
Low Power
5mm
High Power
Star
Super Flux
High Power
Piranna
Package
High Power
Low Power
SMD
SMD
LED lighting: A new notion in the field of Illumination
• White Light Emitting Diode (WLED) is considered to be light source for the
future and are superior to incandescent or discharge technology in many
aspects.
– High luminous efficacy
– Flexibility in luminary design (power rating, configuration, power
source etc.)
– Ease of deployment
– Long life (50,000 to 1, 00,000 hours)
– Quick start
• WLED based lighting is considered to be one of the most viable lighting
solutions for off grid rural areas
LED lighting: A new notion in the field of Illumination
Luminous Efficacy (Lumen/Watt)
LED lighting: A new notion in the field of Illumination
• Market Status
• 2005
6%
9.5%
• 2006
20%
• 2007
• 2008
12%
LED lighting: A new notion in the field of Illumination
• 2012
• Status of LED in Nepal
General purpose lighting for off grid rural villages
Alternative/ Emergency lighting during power cut in urban/suburban
areas
Sign and display (Traffic light, advertisement, mobile devices etc.)
LED lighting: A new notion in the field of Illumination
– Most of the off grid rural areas of developing countries rely on fossil
fuel for illumination
– Required level of illumination is very less for people living in these
areas. Basically for moving around, cooking and reading for children
(2-5 Lux).
– In accordance to early study made in Humla Nepal children are able to
read comfortably under illumination level of 25 lux and 10-15 Lux is
sufficient for cooking and other tasks
– Along with lighting level economy, friendliness to environment,
durability, reliability and robustness should be considered
– Advancement in WLED technology has made it suitable for general
purpose lighting application
LED lighting: A new notion in the field of Illumination
• Comparison Between WLED & Other Sources
Lamp Type
Luminous
Driver
Efficacy
Efficiency
Lumen /
Watt
CCT
CRI
Life
Degree
%
hrs
Kelvin
WLED Low Power
60-90
>90
4800-5500
70-90
20-50K
WLED High Power
80-161
>90
3800-4500
>90
50-100K
Incandescent
10-16
100
3300
95
1K
Halogen
15-20
100
3300-3600
95
3K
Fluorescent Lamp
35-60
80-90
4100
80
10K
Compact Fluorescent Lamp
50-80
80-90 3400-45000
75
15K
Tuki (Kerosene Lamp)
0.08
NA
NA
NA
NA
Jharro (Pine Stick)
0.04
NA
NA
NA
NA
LED lighting: A new notion in the field of Illumination
• Cost Analysis for Solar Home System
– Comparison in terms of illumination
SHS with CFL
SHS with WLEDs
Component
Rating
Price
Component
Rating
Price
Solar Panel
25 W
$49.66
Solar Panel
10 W
$19.86
Charge Controller
5A
$26.49
Charge Controller
5A
$26.49
Battery
38 Ah
$59.60
Battery
12 Ah
$35.76
DC/DC Converters
20 W
$9.9
Drivers
2*3 W
$1.96
CFL
2*7 W
$5.96
WLEDs Lamp
2*3 W
$11.92
Total installation cost
$151.61
Total installation cost
LED lighting: A new notion in the field of Illumination
$95.99
• Running Cost Calculation for Various Light sources
Incandescent
Life Span (hour)
CFL
WLED
1,000
15,000
75,000
Luminous efficacy (lumens/watt)
13
65
160
Power for equivalent illumination level (watt)
60
12
5
$0.25
$2.73
$20.00
4,500.00
900.00
375.00
$450.00
$90.00
$37.50
75
5
1
$18.75
$13.65
$30.00
$469.00
$106.38
$87.50
Cost of lamp (USD)
Electricity used in 75,000 hours (KWh)
Cost of power for 75,000 hours (Average Tariff: $0.1
per KWh)
Number of replacement bulb in 75,000 hour
Replacement cost in 75,000 hours (USD)
Total cost for operating one lamp for 75,000 hours
LED lighting: A new notion in the field of Illumination
• Economic Benefit in Long Run
Total cost for operating one lamp for 75,000 hours
Total number of household lamp
Total cost for operating 15 lamp for 75,000 hours
Saving in 75,000 hours by switching from incandescent to
WLED
Incandescent
CFL
$469.00
$106.38
15
15
$7,035.00 $1,595.70
$5,722.50
$283.20
Saving in 75,000 hours by switching from CFL to WLED
Estimated daily use in hour
Days in month
Electricity use per month (KWh)
Cost of power for one month
Electricity saving per month by switching from incandescent
to WLED
Electricity saving per month by switching from CFL to
WLED
LED lighting: A new notion in the field of Illumination
WLED
$87.50
15
$1,312.50
6
30
162.00
$16.20
6
30
32.40
$3.24
6
30
13.50
$1.35
$14.85
$1.89
Decorative
Lighting
Household Lighting
Flood Lighting
Automobile Headlamps
Aircraft Lighting
Message Displays
Street Lighting
•
WLED is youngest technology in the field of illumination but has already been considered
light source for the future
•
Development of WLED technology is somewhere around middle of its projected level of
efficiency and cost but has already exceeded all other light sources
•
In global context LED has already been accepted as primary source of illumination for
numerous applications
•
In Nepal lack of awareness and industrial development has limited use of WLED as
primary source of lighting in rural areas
•
Developing countries like Nepal should also take this matter seriously and start promoting
“WLED for General Purpose Illumination”
LED lighting: A new notion in the field of Illumination
LED lighting: A new notion in the field of Illumination