You can compare bulbs by checking their efficiencies on a watts to lumens chart.
Luminaire lumens per circuit watt.
Luminous efficacy is a measure of how well a light source produces visible light.
That s more than 4 5 times as efficient as the ge incandescent light bulb.
It is the ratio of luminous flux to power measured in lumens per watt in the international system of units si.
Leds are most efficient.
A 40w equivalent ge spiral cfl light bulb uses 10 watts of electricity to put out 580 lumens so the energy efficiency of that light bulb is 58 lumens per watt.
It is very important to compare this figure correctly other manufacturers may state led efficiency for example which does not include all losses within the system and could therefore be a misleading much higher figure.
Lumens are units of brightness and watts are units of energy.
The luminous flux φ v in lumens lm is equal to the power p in watts w times the luminous efficacy η in lumens per watt lm w.
In calculating the average luminaire lumens per circuit watt the circuit watts for each luminaire may first be multiplied by the control factors in table 45.
Leni is a change of philosophy looking at energy use rather than installed load.
General lighting in other types of space.
So i need to know the levels of luxs that are required for vets and then find a lamp like t8 fluorescent tubes the have a lef of around 85 lumens and.
A light engineering term exists for the measurement of the rate at which a lamp is able to convert electrical power watts to light lumens this is referred to as luminous efficacy or just efficacy and is expressed in lumens per watt lpw or lumens per circuit watt.
Leni lighting energy numeric indicator has also been included as an alternative to minimum luminaire lumens per circuit watt.
The problem is to achieve this 85 lumens per circuit watt i could just install one light in each room that has a lef of 85 lumens this how ever wont light the installation enough for it purpose.
φ v lm p w η lm w watts to lumens calculation.
The 2010 standards introduce a requirement to assess and improve the energy performance of an existing building.
So there are now two options to calculate energy use and show compliance.
The average initial efficacy should be not less than 60 lamp lumens per circuit watt.
Lumens to watts calculator watts to lumens calculation.
Luminaire lumens per circuit watt the luminaire efficiency including all optical and gear losses.
Energy saving lamps have high luminous efficacy more lumens per watt.
Luminaire lumens per circuit watt is the lamp lumens x lor summed for all the luminaries.
