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Lamp Efficency
Efficiency of Different Lamp Types
The job of a lamp is to convert electrical power (Watts) into light
(lumens). Different lamps do this with varying efficiencies.
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Lamp Type
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Conversion Efficency (Lumens per Watt)
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Life (Hours)
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GLS
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10
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1000
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Low Voltage Halogen
|
20
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2000 to 5000
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Mercury Vapour
|
40 to 60
|
22000
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Fluorescent
|
64 t0 90
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7000 +
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Metal Halide
|
70 to 90
|
12000 +
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High Pressure Sodium
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90 to 125
|
25000
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Low Pressure Sodium
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120 to 200
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20000
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The customer should be made aware of lamp efficiencies and operational
life in situations where a lamp is to be left on for long periods
of time or is not easily accessible for replacement. The energy
consumption of a large lighting system is considerable. For example
in a commercial building the energy costs of the lighting system
may be 30 to 50% of the total energy costs.
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