Energy Saving! Lighting costs on low voltage

[The_Monk]

Just working through some figures for some new lights in a room. Now this room is used frequently but not for long periods, anyways...

I've been told that low voltage lighting does not make a difference when working out cost because it is the wattage that counts, e.g. a 50watt halogen bub at 12v, uses the same amount of energy as a 50watt normal bulb. Can anyone shed some light on this (no pun intended)? This does seem to make sense but can anyone 100% confirm this or direct me somewhere that woud tell me? I've been Googling all morning and im going round in circles to the same pages!

[iaint]

The problem with a standard bulb is that most of the energy (watts) is used to generate heat and is therefore wasted energy.

Energy saving bulbs generate less heat than a standard bulb so you get more light per watt.

Therefore you can use a lower wattage bulb than you would if you used a standard one and this is where the savings are made. If you look on the box of an energy saving bulb it will give the wattage of the bulb and an indication of what wattage standard bulb you would need to get the same amount of light.

Hope this makes sense
Iain

[The_Monk]

Originally Posted by iaint

The problem with a standard bulb is that most of the energy (watts) is used to generate heat and is therefore wasted energy.

Energy saving bulbs generate less heat than a standard bulb so you get more light per watt.

Therefore you can use a lower wattage bulb than you would if you used a standard one and this is where the savings are made. If you look on the box of an energy saving bulb it will give the wattage of the bulb and an indication of what wattage standard bulb you would need to get the same amount of light.

Hope this makes sense
Iain

I understand that, it was the low voltage bit that was confusing me. I thought low voltage would mean less cost but apparently this is not the case. I was debating between a flourescent tube and low voltage halogen spots. I was told a 50watt 12v halogen bulb would use the same energy as a 50watt 240v bulb. Just wanted a comparison of costs. Although after working through the sums voltage plays no part in the costing, so now i'm thinking i've been told right.

[iaint]

I've found this on the National Energy Foundation website.

http://www.nef.org.uk/energyadvice/lighting.htm

The main explaination given on that page is for the energy saving bulbs I originally thought you wanted the details on, but I now realise you mean the low voltage 2 pin bulbs in the silver housing.

The last paragraph does briefly cover the low voltage lights though and states:

Low voltage lights are usually small bright halogen bulbs, often needing a transformer to work. They are commonly used in kitchens where they give a bright narrow beam, often requiring several lights on a single unit. Although each halogen bulb uses less power than a conventional light bulb, they use a great deal more than a CFL and if several halogen bulbs are used, they will use more energy in total than conventional lights.

So to answer your original question you would be best going for the energy saving bulbs followed by the flourescent strip lighting. The low voltage bulbs are meant to provide a narrow beam of light and need several to light a whole room.

I hope this is of use
Iain

[The_Monk]

Originally Posted by iaint

I've found this on the National Energy Foundation website.

http://www.nef.org.uk/energyadvice/lighting.htm

The main explaination given on that page is for the energy saving bulbs I originally thought you wanted the details on, but I now realise you mean the low voltage 2 pin bulbs in the silver housing.

The last paragraph does briefly cover the low voltage lights though and states:

Low voltage lights are usually small bright halogen bulbs, often needing a transformer to work. They are commonly used in kitchens where they give a bright narrow beam, often requiring several lights on a single unit. Although each halogen bulb uses less power than a conventional light bulb, they use a great deal more than a CFL and if several halogen bulbs are used, they will use more energy in total than conventional lights.

So to answer your original question you would be best going for the energy saving bulbs followed by the flourescent strip lighting. The low voltage bulbs are meant to provide a narrow beam of light and need several to light a whole room.

I hope this is of use
Iain

Top stuff thanks! I'll be doing my sums now!