RE: Re: Do X10 Dimmers save electricity?

["Paul Gordon" <paul@xxxxxxxxxxxxxxxxxxxxx>]

Is it me misunderstanding fundamental principle's or does that table not
lo=
ok immediately suspect to anyone?

Specifically the efficiency column... - not sure just what is meant by
effi=
ciency in this context, but surely no electrical device ever invented by
ma=
n is 100% (or more) efficient? - If so the multi-mega-million =A3=A3=A3=A3
=
prize for a working perpetual motion machine would have been claimed?

Also, surely something being 120% efficient means that you get more energy
=
out than you put in!! - Surely contrary to the laws of physics!??? - and
if=
it were true, then why not hook up a photocell to regenerate leccy off the=
light bulb and get free electricity!!!

Paul G.


-----Original Message-----
From: David Buckley [mailto:db@xxxxxxx]=20
Sent: 17 February 2005 06:19
To: UKHA_D Group
Subject: [ukha_d] Re: Do X10 Dimmers save electricity?




Found on usenet:

For a standard tungsten filament lamp, the effect of varying the
supply voltage from the rated value (100%) is thus:

Voltage     Light output      Lamp life   Power consumption  Efficiency
110%           140%              32%         115%              120%
100%           100%             100%         100%              100%
95%            80%             200%          96%               83%
90%            65%             400%          88%               74%
80%            45%           >2000%          72%               63%
50%             8%      almost forever       35%               22%

The power savings from dimming lighting are enormous, if you burn
enough hours.  This is why any modern building has controlled
lighting, so as to save money whilst providing the design illumination
level.