On 03/04/2021 16:20, ARW wrote:
On 03/04/2021 14:34, Dave Plowman (News) wrote:

I really hate that when they claim to have the same light output when any
fool can see they're lying. But only after you've bought them.

I'd love to see some truly independent tests of LED versus decent
florries. I've yet to see any which give the same quality and intensity.
And think the claims for energy saving - like for like - vastly
exaggerated.


My outdoor front floodlight has failed. I have just stuck a 50W LED
replacement up until I can get new control gear for the 35W CDM-T.


The 35W was brighter than the 50W and the CRI was much better. It's run
as dusk till dawn and needed a new lamp every couple of years. At £15 a
lamp it seemed a fair trade off.

That outside light is 20 years old and as it has no ferrous components
it has no rust.

Won't the LED be far more efficient?

This suggests:
https://en.wikipedia.org/wiki/Luminous_efficacy
for an LED 100lm/W

Whereas for the 35W CDM-T it will be 79l/W

https://www.lighting.philips.co.uk/p...125_EU/product

I guess the LED efficency will be dependent on the manufacturer, hence
why I tend to go for a name.