LIGHTING SPECIAL FEATURE
Considered collectively , these loss mechanisms can result in a decrease in efficacy of greater than 30 per cent according to the US Dept of Energy . You can ’ t do much about the driver losses but heat generation needs to be dissipated effectively as it does harm the unit – and relatively few LED luminaires are designed with adequate cooling to my mind . However , a manufacturer ’ s choice of components and the design of the luminaire for optical efficiency can all deliver improved efficiency . You could argue that the energy savings are marginal at an individual user level , but it soon adds up for a whole building or business using dozens or hundreds of lights .
Broadly speaking , if you want output similar to an old 60W incandescent , look for around 800 lumens . For the equivalent of an old 40W bulb look for 450 lumens . Do compare the output efficiency . For instance , our LED floodlights deliver over 2,000 lumens while consuming only 32W and in terms of brightness and field of illumination compete with any energy hungry halogen .
Instant LED brightness should now be a given , of course .
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Quality
The biggest inefficiency of all , of course , is poor componentry or quality control so that the product needs to be scrapped or replaced . Saving a few pennies on a luminaire with a substandard driver or PIR switch , or that is liable to burn out from overheating , just does not make commercial sense . Doing a job twice is mightily expensive .
Yes , it ’ s true that LEDs generate relatively little heat – but even this is potentially a problem for enclosed LEDs , especially with outdoor lighting . Where the IP rating is high to protect the luminaire from the elements , the airflow and cooling to the luminaire can be restricted . Gradually , and eventually , the heat produced by the LEDs is going to degenerate the LEDs themselves and the electronic components surrounding . So look for proper cooling fins and pins , not just a few holes in the casing . The 30,000 + hour life expectancies we all have of LED lighting
WE NEED TO STOP BUYING LEDS ACCORDING TO THE ENERGY THEY CONSUME AND FOCUS INSTEAD ON THE LIGHT THEY GIVE OUT ( LUMENS ).
Instant LED brightness should now be a given .
these days are unlikely to be met if the circuitry is consistently overheating . So any design needs to incorporate a cooling mechanism . If the back ’ s smooth , with no cooling fins , then perhaps it ’ s a case of buyer beware !
Another consideration is the PIRs . Whether it is providing outdoor security lighting or automating internal lights and HVAC systems to conserve energy , PIR detectors are everywhere and , just when you thought these were products you could sell over the counter without too much thought , comes a warning about LED compatibility . All LED lamps and luminaires must use a type of driver or voltage reducing circuit as for AC LEDs and this driver or voltage reduction circuit can cause current spikes at switch-on
Not all LED luminaires deliver the same lumens per Watt .
Look for proper cooling fins and pins , not just a few holes in the casing .
Watts vs lumens
We need to stop buying LEDs according to the energy they consume and focus instead on the light they give out ( lumens ). Not all LED luminaires deliver the same lumens per Watt , and their efficiency is a good indication of the quality of design and construction .
While Wattage is the total power consumed by the luminaire after thermal effects , driver losses etc , lumens measure light output after optical inefficiencies , most of which are a function of the detailed design of the unit ( LED arrays , reflectors etc ).
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