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The Pros and Cons of Low Energy LED Lighting

For most people, probably the biggest single factor against low energy  LED   lighting  as a substitute for the soon-to-be-phased-out regular incandescent  light   bulb  is the cost differential. There is no doubt that an  LED  equivalent  light   bulb  (for example a 6w  LED  spotlight as a direct replacement for a 35w GU10 halogen lamp) is significantly more expensive than either the original or a CFL alternative.

There are however three important points to bear in mind about the higher price for low energy  LEDs  as compared to incandescent and energy saving CFL  light   bulbs .

First, the price difference reflects the fact that the use of  LED  for general purpose domestic  lighting  is still quite novel, though increasing manufacturing levels and consumer take-up will drive the price down dramatically once both come fully on stream over the coming months.

Second, and partially related to the observation above, is that the cost of  LEDs  drops by a factor of twenty over the course of each decade. This characteristic is reliably predicted by Haitz’s Law (very similar to Moore’s Law for computer chips and for similar reasons, principally because  LEDs  are, just like computer chips, pure electronic devices). Haitz also states that  LED  performance (amount of  light  per watt of electricity) increases tenfold over the same decade.

Third and perhaps most intriguing is the fact that as far as the cost of domestic  lighting  is concerned, the price of  light   bulbs  is almost entirely irrelevant. It is an extraordinary yet easily provable fact that even if regular  light   bulbs  were totally free and  LED   lights  cost, let’s say something outrageous like $80 each, it would still be vastly more economical to purchase  LED  low energy  lights .

The reason for this is simple: the cost of electrical  lighting  is the cost of the energy i.e. electricity. It matters not one jot what the actual  light   bulbs  cost; it’s what it costs to run them that really counts. Also, since  LEDs  last for tens of thousands of hours (in practice, decades of use) you only need to pay the purchase price once, unlike regular  bulbs  which last only upto two thousand hours or just over one year.

The second biggest gripe about low energy  LED   lighting  is  light  levels and quality, or in technical parlance luminosity and  light  color.

The concern about luminosity stems largely from historical notions of  LED   lighting  applications such as  LED  Christmas  lights  and pocket torches which are clearly not capable of providing anything close to useable domestic  lighting . However, you could right now purchase one of the latest Sharp Zenigata  LED  series of  light   bulbs  which is rated at 80 lumens per watt (measure of luminosity).

To understand what this means, consider that a standard 40w incandescent  bulb  delivers about 360 lumens and a 60w  bulb  about 540 lumens, which gives a ratio of 9 lumens per watt. Anything that offers greater than 25 lumens per watt can be classed as an energy saving  light   bulb . Zenigata  LED   light   bulbs  consume 6.7 watts and thus produce 6.7 * 80 lumens per watt which is 536 lumens, on a par with the standard 60w incandescent  light   bulb .

So you could, right now, replace all your 60w  light   bulbs  with Zenigata  LED   light   bulbs  rated at 6.7 watts and consume 1/10th (or 90% less) electricity. And remember Haitz’s Law? Because of performance improvements, eighteen months from now you should be able to obtain the same 60w worth of  lighting  from just 3 watts.

 LED   light , in common with CFLs, has tended to be a somewhat cool blue colour, whereas we are more accustomed to a warmer yellow white colour. This is something that is now commonly addressed with the use of colored phosphors (these do reduce luminosity but this is in turn compensated for by the ever increasing lumens per watt yields for  LEDs ).

The third factor that might be considered to weigh against low energy  LED   lighting  is that the  light  emitted by an  LED  is intrinsically directional and doesn’t scatter in all directions the way that incandescent and fluorescent  lights  do. This is actually quite acceptable in a spotlight, flood  light  or bright reading lamp, but it’s not especially effective for emulating general ambient  lighting  such as a table lamp would provide. Though again, there are  LED  powered general  lighting   light   bulbs  becoming more commonly available that do a reasonable job here.

Two obvious plus points for low energy  LED   lighting  are ease of retrofit and ecological credentials (other than simply saving energy).

 LED   lights  are widely available for all common base fittings such as mains powered GU10 and 12v MR16 spotlights and the low energy standard base GU24 as well as regular bayonet mounts and Edison screw fittings.  LED   lights  also don’t suffer from the many inherent problems associated with CFLs such as: noticeably poor start-up times; reduced lifespan caused by frequent switching on and off; and bulky unattractive  bulbs .

But perhaps one of the most widely known advantages of low energy  LED   lighting  over energy saving CFL  light   bulbs  is that they don’t contain toxic mercury vapour or other unpleasant materials, and thus do not pose a serious health risk or require tiresome and expensive disposal procedures to protect the environment.

To sum up, the main perceived disadvantages of domestic energy saving  LED   lighting  are cost and application (luminosity and color). Yet as we have seen, the cost of a  light   bulb  is actually a red herring – the true cost of electrical  lighting  is the price of electricity and on this score ultra low energy  LED   lighting  puts everything else, including energy saving CFLs, completely in the shade (pun intended).

As regards luminosity and  light  quality,  LED   lights  on balance deliver a cleaner, sharper  light  than CFL  light   bulbs  and offer far more flexibility in terms of color choice and brightness.

Finally, the biggest advantage that low energy domestic  LED   lighting  has over its rivals is that the  lighting  industry itself regards domestic  LED   lighting  as the future and can barely disguise its contempt for CFLs.  Lighting  giants such as Philips are on record as stating that they will not invest a single dollar further into CFLs and that their entire research and development efforts are now directed at domestic  LED   lighting   technology .

Those who follow eco-technology trends are well aware that there is a world-wide phase-out of incandescent  light   bulbs  already well underway and scheduled to complete within the next couple of years. Given international legislation to ban incandescent  lighting  and lack of support for the already dated and unloved CFL, it’s near certain where the future of  lighting  lies – with low energy  LED   light . And as advantages go, I’d say that one’s pretty compelling.

Source by Megan S Jones

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