fluorescent (?) lights on or off??

jimbob_3

Hi,

im in a school and we are trying to cut our £55,000 yearly electricity bill.

i wonder if there are any lighting experts here who can tell us whether it is better to leave on our fluorescent lights on all day, or turn them on and off when we leave a class room.

each room has at least 4 lights and somebody suggested it took more power to turn them on and off rather than leaving them on?

has anybody got any answers?

thanks

mum2kathryn

Hi Jimbob,

Turn them off!

Old fluorescent lights had a high start-up energy use, but modern ones use a lot less. Certainly if you are going to be out of the room for more than 10 minutes its better to turn them off.
As your energy bill is over £50k you might be able to get a free Carbon Trust Energy survey (you'll need to check if schools are eligible but I don't see why not). They'll send an energy expert to look round the whole school and make recomendations on where you can save energy.
See the carbon trust website www.carbontrust.co.uk .

Niki

mum2kathryn

Just checked - schools are eligible, and there is a special section devoted to schools, with links to relevant publications etc.

www.carbontrust.co.uk/energy/startsaving/schools

Cardew

It is one of the 'urban myths' that have grown up that fluorescent light should be left on to save power.

As stated above they should be switched off.

This is from the Energy Saving Trust( a Government sponsored site)

Question
Is it true that you use more energy to turn lights on and off than to leave them running?

Answer
There is a widely held belief that it is better to leave fluorescent lights (like energy saving light bulbs) on rather than switching them off. It is true that they draw more power when they are warming up however this only takes a few seconds at most so is equivalent to a couple of minutes electricity use when they are on.

Although CFLs do not use much electricity it is still best to keep them switched off when they are not needed as otherwise you are wasting money and energy. If you are going to leave the room for more than a few minutes, turn off the lights.