On 28 Apr 2021 at 00:14:26 BST, ""Dave Plowman" News)"
wrote:

Think it's generally known that dimming a tungsten bulb reduced its
efficiency dramatically. In other words, a 100w dimmed to half brightness
used a lot more electricity than a 50w on full. Although dimming did
extend the life of the bulb.

So how about LEDs? Since they generate far less heat are they still as
efficient when dimmed?

At a guess, if they stay as warm, pretty much, although light as a proportion
of heat is less. If the fitting gets cooler as you dim, then I'd say yes, the
efficiency is fairly linear.

--
Cheers, Rob