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Does using a light dimmer save energy, or does the dimmer just dissipate about the same amount in heat?
Does it depend on the dimmer type?
- Roger Kaiser (age old)
U of I Alum, West Grove, PA
Modern light dimmers are actually much more efficient than they
used to be. Back in the "old days", they were basically just resistors
that limited the current in a circuit. Since resistors dissipate power,
this is a wasteful way to do it. Most modern dimmers use what are
called Silicon Controlled Rectifiers (SCR's), which limit the power
sent to lights by quickly switching on and off rather than by resistive
Have a look at http://www.epanorama.net/documents/lights/lightdimmer.html
(republished on 07/17/06)
Follow-up on this answer.