Building Construction, Renovation, Maintenance & Advice

LEDs Compared With Other Types of Light Bulb

"Lights From Edison Are Dead But His Screw Lives On"

Last week a friend of mine was complaining that the lights in his restaurant keep blowing. He is getting just a little bit peeved with having to keep changing them. His is a problem suffered by probably thousands of people across this island – miniature spotlights.

They look good don't they – when they work that is. The original miniature spots are incandescent lights with halogen inside the glass bulb which makes them burn much brighter than normal light bulbs.

Incandescent tungsten filament lights

Incandescent, of course, means they work by electricity heating a filament so hot that it gives off white light but, unfortunately lots of heat as well.

Back in 1879 a rather clever chappie called Thomas Edison was inventing all sorts of things like phonographs (the forerunner to the ipod) and belly button warmers. He was granted a patent for the first commercially practical light bulb, a design that, with a few modifications, has served us well for nearly 130 years. He really was a bit of genius.

His early production light bulbs had filaments made from carbonised bamboo (I kid you not) and as time progressed the carbon filaments were replaced by far more reliable tungsten.

Halogen lights

Halogen bulbs have halogen gas inside the glass bulb which allows the tungsten to burn even hotter (and therefore brighter) than the ordinary incandescent bulbs. This also makes them fragile so jolting them while they are on or, more likely, fluctuations in the power supply can easily blow them and hence our problem.

The miniature halogen spotlights that have become so popular are known as MR16 lights. MR16 does not, as you might think, stand for “Multiple Replacement 16 times a week” but for Multifaceted Reflector with the 16 referring to the diameter of the front face in terms of the number of 1/8ths of an inch (what strange sort of person thought of that one?) so an MR16 is, in sensible measurement, 2” or 51mm across the face.

Compact fluorescent lights

Over the past few years we have seen huge changes in household lighting as the old tungsten filament incandescent light bulbs have vanished almost overnight to be replaced by compact fluorescent lights. These produce less heat and are far more efficient but they do contain mercury. We can expect that compact fluorescents will be around for quite a while yet but many of us will soon be using LED lighting.

LED lights

LED (Light Emitting Diode) lighting has been around for a few years now but only recently have they become sufficiently developed to be considered a replacement for compact fluorescent lights.

Unfortunately LED lighting has been suffering from an over enthusiastic Chinese manufacturing industry that has been churning out poor quality LEDs by the container load. The market has been saturated with lights that have not been particularly bright, have poor colour and, worst of all, last as long as a cream bun in a kindergarten.

This flood of LED lights has also been particularly frustrating in that many have been designed with the light units built into their fittings so that if the light fails you have to replace the whole fitting.

But now the game has changed, the lighting professionals have done some serious research and we are able to buy high quality LED lights that fit into standard electrical fittings.

Standard lightbulb types and codes that identify their fittings

First let us quickly look at standard light bulbs or, more importantly, the fittings they go into:

Fitting Description Cap Design Comments
ES or E27 Standard A19 light bulb with screw thread. 27 mm diameter screw. ES - Edison screw. US origin used worldwide
SES or E14 Small light bulb with screw thread 14mm diameter screw SES – small Edison screw.
CES or E12 Even smaller light bulb with screw thread 12mm diameter screw CES - candelabra Edison screw
BC or BA22d Standard A19 light bulb with bayonet fitting 22 mm diameter bayonet BC – bayonet cap. British origin used worldwide
SBC or BA15d Small light bulb with bayonet fitting 15 mm diameter bayonet Small bayonet cap
GU5.3 Standard halogen “push in” mini spotlight 12 volt 2 parallel pins 5.3 mm apart Used on 12 volt MR16 miniature spotlight units
GU4 Small halogen “push in” mini spotlight 12 volt 2 parallel pins 4 mm apart Used on 12 volt MR11 miniature spotlight units
GU10 Standard halogen “twist to install” mini spotlight 220 volt 2 bayonet pins 10mm apart Used on 220 volt MR16 miniature spotlight units
G13 Standard fluorescent light tubes 2 pins 13mm apart Used on T8 (25mm dia.) And T12 (38mm dia) tubes
G5 Small diameter fluorescent light tubes 2 pins 5mm apart Used on smaller T5 (16mm diameter) tubes

 

Some years ago I heard that Philips, noted for their very good light bulbs, had stopped all development of incandescent lights and were working on compact fluorescents. They went on to produce what are probably the best compact fluorescent light bulbs available with good warm colour, plenty of brightness and longevity. Their spiral “Tornado” bulbs are particularly good and set a benchmark.

But then a couple of years ago, just as the world was changing to compact fluorescents, Philips stopped all further development of those totally focussing its research efforts into LED light bulbs. They knew the future.

In the past year Philips have released high quality LED light bulbs that set high standards with very good colour, noticeably brighter than other led products available and with a life expectancy said to be in the 10 year range. They fall into 2 basic types.

The first are replacement units for the small halogen 25 and 50 watt MR16 miniature spotlights. The old halogen bulbs look great but they use a lot of electricity and are notorious for blowing easily and don't last long.

Philips LED miniature spotlights are designed to fit into existing MR16 fittings. They come in several different power outputs from 4 to 10 watts and give excellent light quality both in terms of colour and brightness. They also come in 12 volt and 220 volt versions and use the same small transformers that the old halogen mini spots did. Some are dimmable. Unlike the dreary LEDs we have been able to get up until now these really do match the performance of their halogen predecessors.

The second is a “screw in” type of light that fits the same fittings as the old standard A19 incandescent and compact fluorescent bulbs. The most technically advanced light in general production is the Philips L-Prize light so named because it won the L-Prize from the US Department of Energy. It replaces any standard 220/240 volt light bulb with a standard E27 screw fitting. It is LED, uses 10 watts of power while producing as much light as a previous 60 watt bulb and, like an incandescent bulb is fully dimmable. It is said to last 22 years (we'll have to wait a while to see about that), has no mercury in it and, most importantly, it won't fade the curtains (dear me, it must be good)!

So the Edison's incandescent light bulb is now a dead duck but his screw lives on.

Different types of lighbulbs compared

Here is a comparison between different types of light bulbs:

Type Power
watts
Brightness
lumens
Lumens
per watt
Life
hours
kWh
per year
Cost per
year Rp*
Incandescent 60 858 14 1,000 132 Rp 198,000
Halogen 50 870 17 1,000 110 Rp165,000
Compact Flouro 18 880 49 8,000 40 Rp59,000
LED 10 850 85 15,000 22 Rp33,000
LED Philips L Prize 10 940 95 30,000 22 Rp33,000

* Based on usage of 6 hours per day.

As you can see the latest generation of LED lights use only a little more than half of the power per lumen when compared to compact fluorescent bulbs and less than a sixth of the power needed to illuminate the old incandescent lights.

This is only part of the story but is important because, by having bulbs available that replace existing standard light bulbs, LED lighting becomes accessible to the majority of existing houses.

If you go and try and buy a fluorescent strip light these days for your garage or office you may be surprised to find they won't have many in stock. Suddenly the market is offering 14 watt LED strip lights to replace the old 36 watt fluoro lights. They look good too, very compact and light in weight, good colour choice and not too expensive.

LED lights are leading a lighting revolution

You might also note that LEDs are starting to be used for street lights and even flood lights.

We are seeing a revolution in lighting technology and this is only the beginning, LED lighting offers far more potential for creative lighting ideas than the old incandescent lights.

Good quality LEDs are expensive with the miniature spotlights costing almost Rp200,000 ($20) each. But with considerably reduced electricity costs and life times of up to 10 years this high cost can be justified. We can expect prices to fall considerably as worldwide sales climb.

Finally a word of caution. Here in Indonesia the electricity supply is notoriously unreliable with blackouts very common but of more concern spikes and surges that regularly destroy light bulbs. It is a good idea to put voltage regulators on your lighting circuits. Look for a good one that incorporates surge protection.

Copyright © Phil Wilson 2014
This article or any part of it cannot be copied or reproduced without permission from the copyright owner.

17 July 2017 Copyright © Mr Fixit,
Jl Bypass Ngurah Rai, Gg Penyu No 1, Sanur, Bali 80228, Indonesia
Telephone: +62-361-288-789, Fax:+62-361-284-180