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Saving energy Updated: 20 May 2009

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Light bulb power saving Posted by: R M Scaife 12 Jul 2010 10:46pm

If lighting accounts for 7.5% of the average household power bill and standard incandescent lamps are replaced by energy efficient versions then we only save 6% at best. I doubt any householders will notice the saving. We replaced most of our lamps about 3 years ago and nearly all have failed, so much for saving power when the lamps dont last as advertised.

Power Use When Turning Lights On Posted by: Eddie Groves 09 Jun 2009 12:55pm

I've heard from a few different people that switching a light on uses a lot of power initially, and that's why they leave their lights on.

I always though this sounded like an urban myth, was I right?

Reply 1: Posted by: John Cuthbert 10 Jun 2009 12:36pm

Eddie,

I saw a Myth Busters episode where they investigated this for different lighting types. It is true that start up has a spike in energy demand particularly for fluorescents. However the Myth busters conclusion was that the potential saving in this start up usage it very quickly (less than 1 second operating time) out weighed by the power used keeping the light on.

Reply 2: Posted by: Consumer Staff 11 Jun 2009 10:46am

Hi Eddie,

Technically it's true. But the effect is so small you can ignore it. Switch the lights off when you leave the room.

The only possible exception to this are tube type fluorescent lights - the type that go flick-flick-flick-on. They do take more power to switch on than other lamps (they have heaters inside) are are not as well suited to frequent on-off switching as others.

Kind regards,

Bill Whitley
Technical Writer