Compact Fluorescent Tubes & LED Globes
Also known as energy saver globes, they might just become Australian law when standard filament globes are no longer available for sale, but what are they and what are the benefits and pitfalls of using them? Compact fluorescent tubes (CFTs) are built around the same technology as standard baton fluorescent tubes used in most supermarkets as the main source of light.
How They Work
Normal incandescent globes run a current through a filament surrounded by an inert gas. The gas can’t burn or be consumed so it prevents the filament from combusting and prolongs its life. Fluorescent tubes, on the other hand, have a tube starter (which works like a match – a little fire gets the big one going) and they operate by running a current through a compressed gas. In a fluorescent tube it’s the gas which illuminates and provides the light. The pressure of the gas in kelvins (K) determines the colour (temperature) of the light emitted.
In terms of features, the globes tend not to be dimmable, so if you have fittings with dimmer switches, I’m afraid it’s all bad news. To achieve this effect in future, you may have to look at the latest technology dimmable compact fluorescent tubes (at around $20 each they are double the price) or consider ultra low wattage LED technology. In a compact fluorescent tube, there are 2 things that can cause the globe to malfunction: (a) the gas will eventually be useless, and (b) the starter will fail. Using non-dimming CFTs in dimmable sockets will dramatically reduce the life of the globe’s starter if the dimmer is less than 100%. This happens because the starter will be constantly trying to start the tube.
The start time is the time it takes for the globe to begin emitting light once the switch has been turned on. Some brands such as Mirabella, are virtually instantaneous, while other brands like Osram, can take as long as 1.5 seconds. Now while 1.5 seconds doesn’t seem like a long time, it can cause panic in young children and the elderly. I’ve also heard a few stories of elderly people switching the light off again before it has a chance to start and it has made them quite nervous.
This is the globe’s ability to cope with frequently being turned on and off. For example, globes placed in living or dining areas tend to be switched on and left on for an extended period. Our living room globes are switched on at around 5:00pm and remain on until we retire at around 10:00pm. However, the globes in our toilets and in our security sensor lights tend to go on and off more frequently. Some brands such as Nelson, have failed very prematurely in our experience if installed in a toilet or security sensor light, however, you can minimise this impact by increasing the time your security lights stay on with each detection. There is a dial that looks like a clock under every sensor; turn this dial to ¾ of the maximum setting.
When buying CFTs, you might notice different brands will advise a number of hours expected from their product before it fails. I’ve been using CFTs since the time they were only available in specialist electronics stores and they were seen as a bit of a gimmick, and I’ve never been able to determine whether the suggested hours are a minimum, maximum, average, or median result. From my experience I’ve had 10,000 hour globes from Mirabella fail after just 2,000 hours, and similar globes in the same light fitting containing 8 globes have lasted more than 9,000 hours. Same conditions, different results.
In every application in my house, I’ve never had a Nelson globe do more than 1,000 hours and some have failed after just 10 hours. However, of all the brands available, Philips tends to be the most consistent. Banks of their globes in the same light fittings tend to fail within 6 months of each other.
HINT: Before installing compact fluorescent tubes at your place, use a permanent overhead projector marker to write the installation date on the plastic starter or the metal part of the globe. This way you’ll be able to estimate the actual hours you’ve had from your globes. If your globes are real underperformers, solid brands like Mirabella and Philips will replace the product should yours fail under normal conditions much earlier than advertised.
One of the first compact fluorescent tubes I ever bought was a Vision 30w 3100K and it’s made in Korea. It burns for about 6 hours a day, has been serving me very well for about 7 years, and just doesn’t want to die. I bought its replacement about 2 years ago and haven’t yet opened the box yet I estimate it’s done about 14,000 hours. It goes to show that in many cases you just never know.
The temperature of a globe is just another name for the colour of light it emits. Temperature is measured in Kelvin and is normally a number upwards of 3000 but usually less than 6000K. It is a measure of the gas pressure inside the tube; lower numbers mean a softer yellowish orange light while a number from around 5000 to 6000 is a particularly icy pure white. The softest white is referred to as Warm White, the middle of the road colour is called Natural White, and the pure white colour is Cool White.
The more popular colour seems to be warm white because it feels more like a normal incandescent globe; some people find the Cool White makes their home feel too much like an office and is too harsh on the eyes BUT if you read on I’ll share an energy saving tip.
Cool White globes SEEM to give off more light so buy globes using half the power and watch your energy bill drop like a stone. For Example: Mirabella 8w Cool White globes seem to emit the same light as a Philips 14w in Warm White. While this is only an illusion, if you do this across your whole house your power bill is significantly reduced. In speaking to our local power company, most electricity bills in my street are around $680 to $920 per quarter, for mainly double-storey homes, while mine hovers around $240.
The recommended use of globe colours is as follows:
- Warm White: Bedrooms and table lamps.
- Natural White: Living areas, dining rooms, TV room, rumpus, recreation rooms.
- Cool White: Bathrooms, toilets, kitchen, office, laundry, verandas, garage, and external lighting.
While CFTs are much less likely to flicker as they age like their big brothers do, you may find your globes will under-perform and flicker after a while if you buy old technology or old stock. If you rush out and buy your globes from a hardware store this is more than likely going to happen to you. Buy your globes from a high-turnover location like a supermarket and you’ll also find your globes will last a long time from your installation date. I’ve bought dusty old Nelson globes from Bunnings that lasted about 10-20 hours before flickering out to a rather slow death. Getting a refund without a receipt is a story for another day!
As the technology continues to improve, the price comes down while the features and benefits increase dramatically. In general, stores like Woolworths, Coles, and Kmart tend to have the latest technology products at the lowest prices, while at some of the hardware chain stores and warehouses this is not the case! I’ve also noticed that the 5 Woolworths stores in my area tend to lean towards the warm white colours in their Philips and Mirabella ranges so do your home work, shop around, and make sure you map out a plan of your house and what you intend to do before just buying and possibly being disappointed.
In order of preference my favourite brands are:
- MIRABELLA: Lowest power consumption globes. Easiest to fit in the widest variety of light fittings. I also love their 23w replacement for the 150w exterior reflector spot lights. Good technical support and fast replacement globes.
- PHILIPS: Good quality products with very consistent performance. Nice higher power globes for large rooms or external light fittings, and now they have ultra compact CFTs which are perfect for coach lights, bunker lights, and very compact fittings.
- OSRAM: I haven’t owned any Osram globes long enough to comment on their longevity. I like their ultra slim twisted globes, but the long start-up delay can be quite painful. Visitors will often flick the switches on and off, wondering why the globes aren’t working.
- NELSON: I haven’t owned a Nelson globe I liked or that lasted long enough to adequately evaluate its performance other than longevity. In seeking technical support from the company my calls were not returned. Every Nelson globe I’ve bought has eventually been returned to its place of purchase for a prompt refund, however, I've recently noticed they now have some new models so they might be worth another try.
If you think Compact Fluorescent Tubes are ground-breaking and you just love them, don't buy too many spares because L.E.D. technology is well on the way. L.E.D. stands for Light Emitting Diode. It's a small piece of solid plastic containing a filament that emits very directional light. They have been around for well over 30 years but the technology in this area has developed in leaps and bounds in the last 10 years, so much so that they are now the preferred choice for torch users, traffic lights, cyclists, and many automotive applications.
The old 100W globes we used to use in our houses have been replaced largely by CFT globes using only 18W of power (some newer ones only using 15W). Shortly, diffused LED globes will be available to produce the same amount of light while only drawing 1W - 3W of current with a globe life of 100,000 hours or around 100 years. In other words, the power lost in your old copper cables between the fuse box and the globe, will be greater than the current used by the globe. Mirabella is now selling a small range of LED globes through Kmart stores. If you'd like to see more of them being made, you'll need to start buying them. I've bought a few for study lamps and courtesy lighting around my home and they're great.
My Last Hot Tip
The efficiency of light fittings is closely related to their cleanliness. Many light fittings (such as oyster lights) are made of glass, so if you have space in the dishwasher occasionally, put a few light fitting covers in for a good clean - they come out looking great and your lights will seem so much brighter.
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