As I am sure you can appreciate being in the lighting industry I have
access to all sorts of fittings and lamp technologies. Some are great
and some not so great. The GU10 halogen I am afraid definitely gets
rated in the latter category
There are a few reasons why the GU10 halogen is a dud and here they are
in no particular order.
The first reason is cost. GU10 halogens are much more expensive than 12
Volt halogens. The reason for this is simple. There are a lot more low
voltage halogens manufactured in the world and hence the cost is lower.
The next reason they are a dud is their very poor light output. A 240
Volt 50 watt GU10 halogen puts out 800 candelas of light. The equivalent
12 volt low voltage halogen puts out 1450 candelas. As you can see the
light outputs between the two cannot be compared – the 12 volt wins
Another good reason not to go down the 240V halogen path is the lack of
range of globes available. There are only 2 different types of 240 volt
halogen available which are 35 watt and 50 watt. You don’t have a choice
in beam widths, wattage or lamp life. In 12 volt halogens you have a far
greater choice in lamp quality and type and can even buy a globe that
will last 10,000 hours. This is not possible with 240 volt halogens.
Lamp life is one of the most important factors to consider when choosing
between halogen lighting systems. The 240 volt halogen has a very short
life. This is due to a couple of reasons. Firstly there are no long life
versions of the 240V commercially available. The other reason is the
susceptibility of the 240V version to be affected by over voltage. As
the voltage changes on the mains power system the filament in the lamps
cops the whole voltage change where the filament in a low voltage
halogen lamps only gets a percentage of the change as the voltage change
has been reduced proportionally in the transformer.
Do you want to know the worst thing about the 240 volt halogens? Once
you have installed them and you find out about all this good stuff there
is absolutely nothing you can do about it. Sure there are compact
fluorescent GU10 varieties available but they are well short of 240V
halogen light out let alone the 12 volt halogen light outputs
9 watt 2700K Compact Fluorescent Megaman GU10 – 14.4 Lux
35 watt Halogen GU10 – 78 lux
50 watt Halogen GU10 – 104 lux
Do you have a mate that said you should look at GU10 in LED? Don’t even
bother contemplating it. Sure I sell them but unless you are looking for
mood lighting and are going to use alternative lighting as your main
source then don’t go there. They are very efficient in that they don’t
use much power but you would need so many of them to get sufficient
light for every day living that the efficiency just goes out the door.
I am not saying that 12 volt halogens are the preferred lighting option
for your home either but if you like the small recessed halogen
downlight look it is certainly the way to go. I moved into a house and
the previous owner had installed downlights. After initially playing
with LED (to find it was a waste of time) I installed electronic
transformers on all the downlights (as they have less electrical loss
than the old style wire wound ones) and use 20 watt IRC halogens. They
produce as much light as the 50 watt lamps but they give me a 60% energy
saving. The other good thing is that they last 5000 hours (which is
unheard of with a 240 Volt halogen GU10).
If you want to know what I would install if I had the opportunity to
start again – that is a different story!
Hope this helps