down lighter energy saver bulbs

lucky-colm

hi all
i have 57 downlighters in my house these are the ones fitted with a 12v transformer most 35w bulbs with only a few 50w bulbs in there. they are never all on together but there would allways be between 20-40 on at any one time. i am not to sure what the energy consumption is with these as they are ran through the transformers but i do think that they are heavy on juice .

what i want to know is?

is there an energy saver alternative bulb for these?

how efficent are they with the transformers?

where would i get them?

what price are they?

or

woulld i be better doing away with the transformers and fitting 220v downlighters instead i was told that there is no problem getting energy saver bulbs for these, but this would in volve getting an electrician in for a day or two adding to the expense.

so advice on which option or what bulb would be greatly appreciated:D

2011

i am not to sure what the energy consumption is with these as they are ran through the transformers but i do think that they are heavy on juice .

A watt is a unit measurement of power.

The ESB charge you by the unit.

1 unit = 1000 watts for 1 hour.

With a purley resistive load (and a light bulb is almost exactly that):

Volts x Amps = Watts

(or Joule for 1 second = 1 watt)

Transformers are very efficient, nothing is 100% efficient but transformers are in the high 90s.

So if you had two 50 watt 12 volt downlighters switched on they would be consuming almost exactly 100 watts (2 x 50). If they were both switched on for 10 hours they would consume 1 unit of electricity. I dont know the exact price of a unit off hand, but it is in the region of 17 cent.


So regardless of the voltage your downlighters work at (mains voltage or 12 volts) if you want to work out the power consumed all you need to know is the total wattage and the time that they are on for.

So whay use transformers??

You could install 50 watt halogen down lighters that work on mains voltage. They will produce about 40% less light than 50 watt 12 volt down lighters! So for the running cost you get 40% more light. The 12 volt downlighter lamps also tend to give a whiter light and the transformers "self regulate" meansing that they keep the output voltage more constant resulting in extended lamp life.

woulld i be better doing away with the transformers and fitting 220v downlighters instead

The advantage of 12 volt dichroic downlighters like yours are:

1) Light quality is excellent
2) Bulb life is very good if the transformer are good quality
3) Dimmers can be fitted (if the transformers are dimmable)
4) Strike time, (how long they take to switch on completley) is very short.

Personally I would suggest that you install energy efficient down lighter lamps only in areas that are less important such as the hall, landing etc. The light quality is often poor and "cold". Some take 5 minutes or so to warm up fully and even then the light is very much reduced. Pay back can take a long time also as the lamps can be very expensive! The Green Pary are very fond of energy saving lamps, but in reality in thae average domestic installation they will result in tiny savings as lighting only represents a small part of the average domestic electricity bill and the lamps are so over priced.

What you could do is install 20 watt lamps in some areas (about €1.60 each) in areas that do not need so much light or are small, such as the en suite. You would be surprised how much light they give out.

Test one out and see what you think

Davy

lucky-colm wrote: »

is there an energy saver alternative bulb for these?

Yes, you can cfl type, or led

lucky-colm wrote: »

how efficent are they with the transformers?

Yes, you can run efficent on transformers, or for led better to use a led driver to get a longer life on the bulb.

lucky-colm wrote: »

where would i get them?

Wholesalers, or some places sell online now.

lucky-colm wrote: »

what price are they?

Vary, depends what your going for. Rough average €7 a lamp.

lucky-colm wrote: »

or

woulld i be better doing away with the transformers and fitting 220v downlighters instead i was told that there is no problem getting energy saver bulbs for these, but this would in volve getting an electrician in for a day or two adding to the expense.

Depends what you go for, you could use the existing transformers, or for led it would be best to swap the transformer for the led driver. You can also get 230v led. Both led options would required someone with some knowledge. Led would replace 35w no problem, they wouldn't be as bright as a 50w.

2011

you could use the existing transformers

Most down lighter transformers require a minimum load (IBL transformers require a load of 20 watts) to operate properly. LEDs tend to be rated at 1 to 8 watts. This can make things a little more complicated, but not impossible.

This is why "LED drivers" are often used instead of down lighter traffos.

I saw LED GU10s for €20 each! Perhaps they are cheaper now??
I have yet to see them perform to anything like 12 volt dichroic lamps in terms of quality.

Davy

Ye, not all transformers will work with led with some will, straight swap for swap. If they did, i would still advise a change to the drivers, they give a max life for the lamp.


Leds wouldn't give as good light no, but they would be ok to replace 35w imo.

davelerave

they're not equivalent but the reduced 'heat output' and 'long bulb life' are big plusses for installer and user when using led/cfl.

eoghan.geraghty

OP You have heard correctly, the greatest renge of energyefficient lamps are available in 220v, known as GU10 fittings.
I would agree with 2011, start off with areas where quality of light is not as important, ie, hall, stairs and landing.
There are some reasonably good cfls and leds for this, one is ecopal, price 8.50 plus vat in eurosales.
I wouldn't recommend swapping out your whole house right now.

I wouldn't buy any cfl/led gu10 or similar lamp for 7 euro, not worth a ****e.

lucky-colm

ok

what we have so far

options:

1; there is energy saver allternative that cost roughly €7 each

2; could get led equivelent but would have to replace transformers with led drivers and light may not be as good

3; alternativly oust the transformer fit gu10's at a cost of between €8.50 and €20 each with slow light up time.

realistically option 1 seems to be the winner but at €7 a bulb i think i will only change a few at a time