I am a great fan of LED lighting as the preferred method of low energy lighting and have successfully incorporated replacement LED lighting in several residential projects over the last couple of years. I am pleased to say to the total satisfaction of the owners. Therefore, inspired by the clarity of an article I recently read, I wanted to share these reasons. This blog might look counterintuitive at first glance, but having read it I may have convinced you that compact fluorescent light bulbs (perceived to be ‘energy saving’) are in fact redundant and that LED lighting is the future.

This does not just apply to the lights in the home – I also believe that the days are numbered for commercial fluorescent lighting as well.  


Reason 1 - Bulk: Every CFL bulb needs built-in ballast which acts to limit the current flowing into the bulb. This little box is why the bases are usually quite cumbersome-looking and may not fit into the socket. LED equivalents are available which match the halogens for light, and which fit with no problems at all.


Reason 2 - Dimming: Whenever you twist a dimmer switch, the voltage reaching the bulb is reduced. Tungstens and halogens can handle this without any problems. CFL bulbs start to strobe and will go pop very quickly. Most LED's are now dimmable.

Reason 3 - Energy Efficiency: The energy ratings on packets of light bulbs (the A-G rating) are measured on how much light (lumens) are produced per watt of power. A tungsten bulb will create around 12-18 lumens (which is very low), a halogen bulb 15-24 lumes (also low), CFLs 40-80, LED's 50-100 lumes. Another way of looking at this is that a 4W LED is the equivalent of ten 40W tungsten bulbs or two 9W energy savers.

 

Reason 4 – Compatibility & Flexibility: You can now buy LED bulbs that fit into a normal fitting which can come complete with a remote control. Not only are most LEDs now dimmable but it is also possible to change the colour as well. This may not be a day to day requirement or appropriate in the majority of instances but it is certainly a useful application in some circumstances.

 

Reason 5 - Instant Light: When new, a CFL is fast and bright but as it gets older the start-up and warm up time gets longer. The smaller the bulb is (for example halogen shape equivalents) the worse the delay. LED bulbs are instant and immediately 100% bright.

 

Reason 6 – Life Span: Tungsten bulb 1,000 hours, CFL bulb 5,000 hours, LED bulb 25,000 hours. The LEDs long life span not only represents a saving in the cost of having to replace bulbs but also represents a maintenance/services cost saving.

 

Reason 7 - Money Saving:

LED bulbs are more expensive to buy than CFL bulbs but the running cost/whole life cost savings are huge.

-          One 40W light bulb, used for four hours a day for a year at 16p a kilowatt equals £9.30 a year.

-          On the same basis a CFL equivalent costs £2.10 to run.

-          On the same basis an LED equivalent will cost less than a pound a year to run.

 

Therefore the potential savings more than make up for extra initial purchase price. A good illustration of this is for example in a commercial setting, changing 100 fluorescent tubes running 10 hours a day for LED equivalents would result in a saving of around £2,500 a year 


 Reason 8 - Mercury: LED bulbs do not contain mercury. Mercury is dangerous, expensive to dispose of and sits inside every fluorescent tube and CFL.


Reason 9 - Phosphor: This is used as a coating on the glass of fluorescents to give us a white glow. The problem is that we apparently have a world shortage of phosphor. This means prices for all fluorescents and CFLs are going to rise as manufacturer costs go up.

 

Reason 10 - Shapes and sizes: There is no CFL equivalent for capsule halogens or 12V downlights ...there are LED equivalents.

In conclusion: CFLs are difficult to dispose of, they need to warm up, they can't be used in all fittings and they can't dim. Tungsten produce less than 5% light for the power they use, definitely not a player in an energy efficiency world.  LEDs are energy efficient, flexible, have an extremely long life span and can also change colour via remote control (should you wish).

If you have not yet changed to energy saving bulbs, you should seriously consider LED bulbs and watch your electricity bill drop. If you've already got energy saving CFLs, it's probably not financially sensible to replace them with LED's until they reach the end of their life.


jb@riba.co
www.architectdevon.com
www.jonathanbraddick.co.uk