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Energy saving LED home lighting is without doubt the future of domestic lighting. Though some critics still harp on about cost and comparison with conventional domestic lighting solutions, they miss the point as completely as comparing an abacus with an electronic calculator.
And, as ever, it’s the money that really talks. A typical 50w GU10 halogen lamp costs about £3 GBP in the UK and lasts (let’s be generous) 2,000 hours. An EXERGI LED equivalent (a high quality UK brand) will at present set you back 7 times that but will last 25 times longer; so on true like-for-like purchase costs you actually save (3*25 – 21) £54.
But that’s not even close to being the end of the matter; assuming modest domestic usage of 5 hours per day, the electricity savings from just one LED bulb compared to the equivalent brightness halogen lamp work out at £19.83 per year and £543.21 over the full lifespan of that one light bulb.
It may not seem like much but if you’re like most folk your lighting usage is almost certainly somewhat is excess of one bulb for five hours per day. If you crank the maths you start to see typical savings for an average household that start at £400-£500 per year (or £11,000 – £15,000 over the typical lifespan of an LED) and go up from there.
You want to leave that kind of money on the table?
The critics are right on one point though – LED lighting is not the same. Low energy domestic LED lighting should be installed, used and thought about differently because the new generation of home LED lights makes possible a whole new world of innovative, adjustable and cost-efficient designs never before dreamed of.
One of the most straightforward ways to begin your move to energy saving LED home lighting technology is by replacing your halogen lamps, since retrofit LED spotlights are fully compatible with the various types of existing halogen fittings (GU10, MR16, ES) and provide a similar form of light i.e. very bright and directional.
Replacement options commonly include GU10 LED bulbs for mains voltage, MR16 LED for 12v lighting and the new GU24 base introduced for low power consumption light bulbs (this was originally intended to delineate CFL bulbs before LED technology started parking its tanks on the low energy lighting lawn).
Note: Originally all light bulb fittings were designated ES (Edison Screw), sometimes abbreviated to E i.e. E27 or ES27 (ES26 in the USA). The numbers designate the size of the lamp fitting i.e. the base diameter in millimeters. Later developments include the Bayonet Mount i.e. B22 or BC22 common in Europe. Rival manufacturer Westinghouse, invented the bi-pin fitting to get past Edison’s patent and this is prefixed by G or GU. However, the popular GU5.3 standard for low-voltage fittings has become commonly referred to as MR16.
So what actually is an MR16 lamp? The prefix MR stands for Multifaceted Reflector and the suffix 16 is the diameter expressed in eights of an inch, so 16/8 is 2 inches across at its maximum width. The MR11 format is thus basically the same but quite a bit smaller.
The reflector is what controls the beam angle and color of the light from the lamp, and a multifaceted reflector has small dimples (facets) which result in a much softer light and reduces harsh contrasts. Note however that it is possible to obtain MR16 and MR11 lamps that have smooth (non-faceted) reflectors.
Most people associate MR16 spot lights with 12v low voltage lighting, but many MR16 lamps are suitable for use with unmodified mains voltage. The difference is in the type of base. What most people refer to as MR16 spotlights use the 2 pin GU5.3 base whereas main powered MR16 spots use the twist lock GU10 base and have thus come to be commonly termed GU10 lamps.
So there you have it; MR16 denotes the type and size of the bulb and strictly speaking the low voltage variants should be described as GU5.3 MR16 and the mains powered types GU10 MR16. The picture below shows from right to left GU10, MR16 (GU5.3) and MR11 light bulbs.
As a generalisation it is common to find that for recessed spot lights (which these days pretty much means halogen lamps) most people opt for MR16 GU5.3 low-voltage lamps and for track mounted lighting they choose instead GU10 line voltage (mains) lamps. The main reason for this split is probably simply to do with the practicalities of fitting the light bulbs. Also, many desk lamps use low voltage simply because with 12v lighting you can make significantly smaller bulbs such as the popular G4 halogen capsule.
The twist and lock mechanism on a GU10 bulb means that you need to maintain a firm grip on it, which is near impossible if the darn thing is recessed inside a hole. Some manufacturers supply a rubber suction cup that attaches to the face of the bulb and makes this slightly easier, but by and large most folk solve this problem by using push fit bi-pin GU5.3 MR16 bulbs instead.
But fitting and replacing bulbs aside, what are the essential advantages and disadvantages of using either mains or low voltage lighting?
Low voltage bulbs actually consume slightly more electricity since although the lamps may use a low-voltage input, the transformers certainly don’t, and in combination they draw more power than mains equivalents. Remember that On the plus side though, low voltage halogen lamps typically last longer than mains versions. A typical line voltage bulb will last about 1000 hours in contrast to a low voltage equivalent that can last 2 to 3 times longer. Needless to say, neither really compares to LED lifespans which average about 50 times longer than a stand mains voltage lamp.
Low voltage lamps are noticeably brighter, the reason being that they burn at a higher temperature and use shorter, thicker filaments, which means a more intense light is produced from a smaller area and thus appears sharper and brighter. However there is an obvious downside to this, namely that they get very hot and, depending on where and how they have been installed, can pose a fire risk. This can be offset by using aluminium (or aluminum if you’re American) backed lamps to project the heat forward rather than back into the recess, and also by fitting fire resistant hoods.
Another notable benefit with low voltage lamps is the enormous range of styles, wattages and particularly beam angles whereas line voltage lamps offer much less choice.
Both types tend to be easily dimmable, but low-voltage halogen lamps are especially well suited to dimming, assuming you have suitable transformers. On the subject of which, it is normal practice to configure one transformer per lamp since it makes the wiring much easier and the overhead cost is not that big a deal. It’s worth noting however that low voltage transformer can emit a distinctly audible buzz which is made worse by using them in conjunction with dimmers. The best solution is usally nothing more complicated than ensuring you fit good quality electronic transformers and suitable low voltage capable dimmers.
When it comes to LED lighting, the same broadly applies except that there are no issues with heat or differences in luminosity. What is not so straightforward however is the topic of LEDs and dimmers.
Halogen lamps in general, and halogen spotlights and down lighters in particular, are very popular and have become extremely common in many households. Used in lighting clusters in kitchens, bathrooms and hallways especially they can really bring a space to life with excellent light coverage that creates a uniform and clean, bright look.
But like most conventional forms of domestic lighting, halogen spot lamps are terribly inefficient and use far more power than is necessary since nearly all the energy is wasted as heat, which brings with it the further problem that they run incredibly hot and often require fire-rated covers. They also don’t last that well with bulb replacement required after about 2,000 hours of use.
To put bulb life figures into context, if you use a lamp for approximately 4 hours each evening you would use nearly 1,500 hours each year.
Overall then , the running costs (or total cost of ownership) for halogen lamps are certainly nowhere near as dreadful as for normal incandescent lighting, but with rising fuel bills and creeping legislation targeted at energy efficiency this is still Not A Good Place To Be ™.
But there is a very simple solution. Although LED energy saving lighting has yet to fully penetrate the domestic market, it does already provide a simple and very effective substitute for domestic halogen lighting, especiallly in areas such as kitchens, bathrooms and hallways.
A quick trip to any good lighting store and ten minutes replacing bulbs is all it takes to install mains or 12v LED kitchen lighting that is equivalent in brightness to old 35w halogen lamps; and in an area such as a kitchen that typically gets a lot of use in most homes that can add up to significant electricity savings just by itself.
Energy saving retrofit LED lamps roughly equal to 50w halogen lamps are now commonly available (particularly GU10 LED lamps) but with output running at 4w – 7w instead and nearly all those watts producing light with almost none lost as heat. The cost comparison for LED is simply staggering in terms of overall financial savings.
Ironically, where energy saving LED home lighting does not yet fully compete (in the area of non-directional table lamps and the like) the increased availability of halogen equivalents for regular GSL bulbs provides an opportunity to replace ordinary household bulbs with halogen lamps while at the same time replacing halogen mains powered and 12v lights with ultra low power LED lamps.
Of course, if you don’t already have halogen lighting installed somewhere in your home then you aren’t constrained by retrofit isssues and could switch directly to an energy saving domestic LED lighting installation and gain all the benefits of a great look with super low energy consumption and running costs and the smug satisfaction that at least you’re not wasting precious energy (and paying for it)!
Halogen lamps cannot be easily replaced with standard low-energy CFL bulbs. Not only are the fittings unsuitable, CFL bulbs are bulky and frankly ugly with a poor light quality. They are also with rare exceptions not dimmable. In fact, there are so many problems with CFL light bulbs that they are realistically a non-starter as retrofit substitutes for halogen spotlights,
However, both low-voltage and mains halogen bulbs can be very simply replaced with equivalent GU10 LED bulbs (for mains) or MR16 LEDs (for 12v lighting) and the benefits are considerable.
For a start, even though the initial costs for LED low energy light bulbs are quite a bit higher than for regular halogen fittings, they last a great deal longer; somewhere in the order of 50,000 hours compared to a measly 2,000 for a standard halogen (some mains GU10 LED bulbs now claim in excess of 90,000 hours). That’s a staggering 30 to 50 years from one bulb!! Most conventional bulbs currently available last only slightly over 1 year.
Put another way, whatever the initial cost for purchasing your domestic LED spot lights, divide by 25 (50,000 hours compared to 2,000 gives a ratio of 25:1) to arrive at the true purchase price compared to an ordinary light fitting, as this then accounts for the very low power consumption and replacement frequency of energy saving LED home lighting.
But that’s just the capital cost. You also need to factor in the fact that domestic LED lighting (whether mains AC or 12 volt DC) uses a fraction of the energy required to power conventional lighting. And also consider that whereas regular lamps waste up to 98% of their input energy as heat (not light), LED light bulbs output almost no heat with almost all the energy converted to pure light.
So the real capital cost of switching to LED home lighting is actually a fraction of the upfront figure and you can look forward to years and even decades before you ever have to change another bulb. All the while costing peanuts to run, as fuel and electricity prices continue to ramp up, making those conventional light bulbs ever more expensive to both run and continually replace.
There are a few key points to consider before you install home LED lighting systems.
First, the low power consumption of LED lamps means they use tiny amounts of electricity – a replacement for a very bright dichroic MR16 12v light bulb rated at 35 watts would be less than 5 watt – so become familiar with the ratings for LED lamps. Update: Less than 2 months on and the common replacement for a 35w halogen lamp is now a 3w LED. To keep pace with the rapid rate of development in this area check out this review of LED replacements for halogen lamps.
Note: you might have noticed the term “Dichroic Halogen” used a fair bit to describe some halogen bulbs – if you don’t know what it means, it simply refers to the special reflective coating used on MR16 halogen lamps that reflects more heat and light and helps keep the lamp body cool.
This very low power consumption means you also need to consider transformers (for low-voltage 12v LED lights) and dimmer switches. Regular dimmer units and 12 volt light transformers require a minimum load and unless you are driving a lot of 12v LED spot lights there won’t be sufficient load and you will need to replace existing transformers and dimmers with special 12v constant voltage LED drivers (as LED transformers are termed) and LED dimmer switches if dimmability is an issue.
A typical unregulated 12 volt transformer is designed to push out 12v when attached to a “normal” load such as 6 x 25w; if you decrease the load down to the tiny amounts that LEDs soak up, the output voltage is likely to increase. This can easily and rapidly lead to premature failure of your expensive 12v MR16 LED light bulbs, so be aware and ensure that you are using regulated transformers or drivers that will not exceed the expected voltage. A solution that many adopt is to simply leave one halogen bulb in the circuit as this will normally increase the load sufficiently. Find out more here about LED drivers and dimmers.
Second, check the beam angle. Generally speaking these should match up easily with halogen spotlight angles which are often in the 36 – 40 degree range, but it is worth confirming. A common cause of confusion is misunderstanding between luminous intensity and luminous flux, or in plain English brightness and total light output. A narrow beam angle focuses all the light into a small but very bright area whereas a wider angle disperses the light more evenly but less brightly.
The point is that a narrow beam LED can appear brighter yet deliver less overall light than one using a wider angle. If in doubt check the rated luminous flux measured in lumens (abbreviated to “lm”) or better still ask for the “Standard Wattage Equivalent” – in other words how it compares against a conventional incandescent lamp of known brightness.
Third, the light emitted from LED light bulbs is pure in colour. Unlike traditional light bulbs which give off a wide spectrum of light, LEDs emit a single color so you should check the color (or more specifically, color temperature) will be suitable for your intended purpose.
White light can vary between “cool” white and “warm” white (hence the term “color temperature”), giving either a closer approximation to daylight or to a conventional incandescent light source. The bulbs themselves contains a cluster of about 20 individual small LED units and can thus be manufactured to produce any given mix of color by varying the colors of the individual LED units.
The best match with halogen lamps is produced by warm white LEDs in the range 2700 – 3500 Kelvins; temperatures higher than about 4000 K start to look quite bluish and rather stark, thought they can be used to good effect in some circumstances (modern kitchens for example).
The best advice is to try and see your intended purchase in use, or at least in a photograph, before you buy. These bulbs are not (yet) especially cheap and do last for potentially decades. A good place to start is LED kitchen lighting, as discussed more fully below.
Lastly query what is meant by “expected lifespan”. LED luminosity decreases slowly over time and the universally agreed point at which an LED reaches the end of its useable life is when its luminous flux (total light output) hits 50% of its orginal luminosity.
Most manufacturers do state the correct “useable” lifespan but some less scrupulous (or ignorant) suppliers will bandy about total lifespan figures. Most LEDs available today last effectively for up to 50,000 hours (i.e. they’ve lost 50% brightness at that point) so you can usually take claims of 100,000 hours with a large pinch of salt. If in doubt, base your calculations on half what the manufacturer claims – you’ll still be making huge savings even then.
If you already have mains powered GU10 halogen lamps anywhere in your home then you can experiment right now with energy saving LED replacements, since retrofitting halogen lamps with GU10 LED bulbs really is just a matter of unscrewing your old halogen lamps and replacing with retrofit GU10 LED equivalent fittings.
For MR16 12v lighting a transformer is already required to run each conventional low-voltage halogen bulb and these may need to be replaced with an LED “driver” (the term used to describe an LED transformer, confusingly also sometimes called a constant voltage controller) in order to power 12v LED lights.
Once all the transformers have been replaced with one or more LED drivers then again it is simply a matter of pulling out the old halogen bulbs and substituting equivalent 12v LED replacement spot lights in their place since the actual fittings are identical for the specific purpose of ensuring LEDs can be easily retrofitted.
Phillips, an established global leader in lighting technology are “betting the farm” on the new generation of home LED lighting that is only now starting to become available to consumers.
The Phillips Color Kinetics eW MR16 12v 5w replacement spot lamp that works with an existing 12v AC transformer and can be dimmed.
As noted above, LED spot lights are ideal for kitchen lighting. Many people already incorporate halogen downlights in their kitchen design precisely because it provides a clean crisp light quality with excellent CRI (Color Rendering Index – how vibrant and true to life things look under articificial lighting) properties that CFL light bulbs can only dream of.
Modern LED bulbs provides the same excellent light quality as halogen spot lights but without the super high temperatures and at a fraction of the running cost. If there is one room in the house that gets most use and where the lights are of necessity switched on for long periods, it is the kitchen.
And yet it is so incredibly simple to pull out existing halogen lamps and in their place push in LED spotlights. Sharp, for example, offer the Zenigata LED Series that can rival a traditional 60w spotlight but consuming just 6.7 watts – in other words costing 1/10th as much to run. That of course is quite bright, even for kitchen lighting, and many would opt for 3 to 4 watt LED bulbs which are equivalent power to 35w halogen lamps.
Kitchen lighting is available in both GU10 LED mains format and as low voltage 12v MR16 LED bulbs, and the savings are such that it actually makes sound financial sense to pull out and throw away existing halogen lamps even if they’re are still fullly functional. In fact, leaving halogen spotlights in situ and waiting for them to fail could cost more in unnecessarily high costs (compared to LED lighting) than dumping perfectly good bulbs.
A common way to illuminate display cabinets, kitchen dressers, open shelves and the like has up till now been with 12v low-voltage slim-line halogen downlighters, typically using the small 10w G4 halogen capsule bulbs. These certainly provide excellent crisp lighting but suffer from the problem that halogen bulbs get very hot. There are now plenty of slim-line LED downlights that provide comparable light quality but generate negligible heat.
These slim-line LED cabinet lights are widely available for both mains and low-voltage fittings and provide plenty of choice in power, ranging from 1w thru to an ultra bright 8w, with fixtures covering surface mounted (6mm depth is common), recessed, round, square and rectangular in a variety of sizes. Each unit typically contains 12 to 20 SMDs (surface mounted diodes – a cluster of individual LEDs) and offer a choice of colors, including color changing.
Best of all, cabinet and other forms of display lighting tend by nature to be awkward to get at for changing bulbs, but with the extremely high lifespan of LED cabinet lights you can more or less fit and forget.
Anyway, that’s it. Job done. Now just switch the lights on without worrying about what it’s costing you or the harm it’s doing to the environment. How simple was that?
Simply replacing those halogen spot lights you’ve got in the kitchen and bathroom (and wherever else you have these ubiquitous little devices installed around your home) with low power consumption LED spotlights (either mains GU10 LED bulbs or 12v low voltage MR16 (GU5.3) or GU24, dichroic or non-dichroic) will save you big money down the line as energy prices just keep on climbing.
Not only that, home LED lighting opens up a new world of lighting ideas that were until recently simply not possible.
You don’t have to make huge sacrifices to save on household energy bills or to reduce your carbon footprint. Energy saving LED lights have very low power consumption, very low heat output and a very long life. Replacing halogen lamps with energy saving LED lighting will save you money and help save the environment.
Furthermore, you don’t have to switch to LED low energy light bulbs all in one go. You can quite easily combine a mix of LED low energy light bulbs and halogen spot lights in order to reduce the initial outlay and also blend the light levels. Or tackle one area at a time, for example install LED kitchen lighting then maybe move onto bathroom lighting later.
This is straightforward with GU10 LED mains powered lamp fittings since you can mix and match halogen and LED lamps at will to suit your requirements.
With 12v low voltage MR16 LED fixtures, you would be best advised at present to use separate circuits (unless it clearly stated that both types of lamp fitting can be attached to the same circuit – as is often the case with for example 12v LED garden lighting). Although it might appear to be extra effort to use dedicated wiring for your 12v LED lights this does set things up nicely for further down the line if you choose to go the next step and generate your own electricity and run solar powered lighting.
Also be prepared to accept that you won’t always get it right first time. Replacing incandescent bulbs with LED versions is still a bit of an art and it takes a bit of getting used to the differences. But if you do, for example, buy some LED G4 or MR11 compatible lamps and find they’re not quite what you wanted for indoors, then consider reusing them elsewhere. They can be put to good use as garden lighting or used around the house as night lights perhaps. Some folk rig up indoor PIR sensors that switch on low level LED lights at night so that people can move around safely without having to switch on a blaze of lights.
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