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Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient...

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Are LEDs an efficient light source for high mast lighting? by Johann Schleritzko
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Page 1: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

Are LEDs an efficient light source for high mast lighting?

by Johann Schleritzko

Page 2: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

Are LEDs an efficient light source for high mast lighting?

Goldwyn Lighting claims, by converting existing high mast lighting to LED light sources:

BEKA states that LEDs are not suited for use on high mast

lighting, since:

• An energy saving of 80%

can be achieved.

Their use will not result in

energy saving

• Higher lighting levels are

attained.

To achieve the same lighting

levels, as their HPS equivalent,

capital costs would have to be

be 8-10 fold, without any energy

saving benefit.

Page 3: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

LED system efficacy:

LED system efficacy =

LED efficacy x driver efficiency x optical efficiency x Thermal efficiency

Page 4: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

Efficacy of light sources

Page 5: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

Driver efficiency:

220/230 V ~ AC/DC Power Supply

24/48V Current Source

350 mA

LEDs + PCBs

EFFICIENCY

85-90

%

90-95

%

72-86

%

X =

Page 6: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

Optical efficiency:

Optical efficiency of TIR optics:

85 % - 90 %

Additional cover glass

+ ~ 8 % losses due to Fresnel reflection

Page 7: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

Thermal efficiency:

LED efficacies are specified at a junction temperature Tj = 25 °C

Realistic condition: Tj = 70 °C Efficacy ~ 90 %

70

Page 8: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

LED system efficiency:

LED system efficacy =

LED efficacy x driver efficiency x optical efficiency x thermal efficiency

120 lm/W x 90 % x 90 % x 95 %

= 93 lm/W available

Page 9: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

Luminaire power

Lumen ( lamp )

Lumen / system efficacy

Efficiency (PRL floodlight )

Lumen floodlights

Utilization factor k ( area lighting )

Lumen on the area

High Mast 9*400W

HPS-T flood lights

9*432W=3,888W

9*55,000=495,000lm

495,000/3,888=

127lm/W

77 %

381,150lm

70 %

266,805 266,805

80 %

333,506

80 %

93lm/W

416,882

4,482W

(15% more)

LED (93) lm/W)

Let us compare power:

Page 10: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

Let us compare power:

High Mast 9*400W

MH-T flood lights

LED (93) lm/W)

Luminaire power 9*432W=3,888W 2,608W

(33% less)

Lumen (lamp) 9*32,000=288,000lm 242,550

Lumen / system efficacy 288,000/3,888=

74lm/W 93lm/W

Efficiency (PRL floodlight) 77 % 80 %

Lumen floodlights 221,760lm 194,040

Utilization factor k (area lighting) 70 % 80 %

Lumen on the area 155,232 155,2325

Page 11: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

Let us compare costs:

High Mast 9*400W

HPS-T flood lights

LED (93) lm/W)

Luminaire power 9*432W=3,888W 4,482W

(15% more)

Capital Cost Floodlights 9*2600=

R23,400

R 189,000

(estimated)

Energy Costs/annum (0.5R/kW) 8,500 9,800

Saving per year 1,300

Page 12: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

Let us compare costs:

High Mast 9*400W

MH-T flood lights

LED (93) lm/W)

Luminaire power 9*432W=3,888W 2,608W

(33% less)

Capital Cost Floodlights 9*3000=

R27,000

R 110,000

(estimated)

Energy Costs/annum (0.5R/kW) 8,500 5,700

Saving per year 2,800

Page 13: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

Verification by SABS:

Page 14: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

Verification by SABS:

Page 15: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

Comparison, based on Goldwyn’s claims:

Luminaire power

Lumen ( lamp )

Lumen / system efficacy

Efficiency (PRL floodlight )

Lumen floodlights

Utilization factor k ( area lighting )

Lumen on the area

Actual Measurements ( average )

High Mast 9*400W

HPS-T flood lights

LED flood lights,

8*250W

9*432W=3,888W 2,000W

(50% less)

9*55,000=495,000lm 186,000

495,000/3,888=

127lm/W 93lm/W

77 % 80 %

381,150lm 148,800

70 % 80 %

266,805 199,040

(55% less)

3.17 1.35

(57% less)

Page 16: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

1. The claims made by Goldwyn Lighting that:

• 80% energy saving can be achieved, and

• Resulting in higher lighting levels

are incorrect.

2. The LED technology is, based on today’s LED efficacy not

suited to achieve energy savings for High Mast lighting

installations.

3. We urge all serious lighting companies to refrain from

making misleading statements, which would harm the

markets long terms acceptance of LEDs.

Page 17: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

17 BEKA LED Seminar 01 June 2010

LED Efficacy

HID 100 lm/W

White LED 80 lm/W

50% utilization efficiency 70% utilization efficiency

Effective: 50 lm/W Effective: 56 lm/W

Utilisation coefficient

Page 18: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

Street lighting: Let us compare power:

Street light 250W MH-T

(92lm/W)

LED (93) lm/W)

Luminaire power 285W 145W

(49% less)

Lumen (lamp) 23000lm 13,600lm

Lumen / system efficacy 23,000/285=

80lm/W 93lm/W

Efficiency (PRL floodlight) 77 % 80 %

Lumen floodlights 17,700lm 10,900

Utilization factor k (street

lighting) 43 % 70 %

Lumen on the road 7,600 7,600

Page 19: Are LEDs an efficient light source for high mast lighting? highmasts.pdf · Are LEDs an efficient light source for high mast lighting? Goldwyn Lighting claims, by converting existing

Conclusion:

LED technology is well suited to achieve energy and cost

savings in many applications as of today!


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