On Thu, 16 Nov 2017 10:03:26 +0000, Clive Page wrote:

On 15/11/2017 13:48, Brian Reay wrote:
I'm unconvinced re LED lights in the domestic setting, not so much due
to the life (although it is good to see a seller honouring his
warranty) but more the light output.Â* We have them in our motorhome
and, in the confined space, they are OK. However, we tried them in the
kitchen (replacing some halogen bulbs - 2x40W halogen per fitting) and
with LEDs they were hopeless. I forget the rating of the LEDs but they
were, supposedly, equivalent to 40W bulbs. At a guess, they were more
like 25W.

It must depend on the type of bulb and the context, because I've found
the opposite. These 13W bulbs have a rated output of 1060 Lumens which
is supposed to be equivalent to 75W of incandescent filament. But I've
put them in places where there used to be 100W or even 150W
incandescents and found them adequate, because, I think, they are not as
omnidirectional. Since more of the light goes downwards which is where
we need it, the effective brightness is rather similar.

But one thing I forgot to mention: the replacement LED I got has an
almost identical box to the original except that (1) the price is 50%
higher, and (2) the guarantee has gone down from 3 years to 2.
Obviously I'm not the only one to have had a bulb fail after just over 2
years!

Well, 13W for a mere 1060lms is only 81.5 LPW, an efficiency level we've
put up with for almost 5 years now. Even Home Bargains offer a much
better 1520lm 12W "100W" lamp at a mere £2.99 in both LES and BC22 forms
with colour temperature options, from memory, of 2700K to 6500K[1].

If you can spare the odd 3 quid, it seems to me it would be worth your
while paying Home and Bargains a visit to pick up one of these lamps. Be
careful over the colour temperature choice though otherwise you might
grab a 6500K lamp by mistake which most of the population would deem a
little too cool (or thin) for comfort.

BTW, £18 for a mere 1060lm lamp is even more expensive than the price of
the 1600lm 12W LEDs being sold in Asda. Considering their competitive
pricing on general goods and produce, either their electrical buyer
doesn't keep abreast of LED technology developments and pricing or, more
likely, they're just taking the **** out of their customers with massive
mark ups on LED lamps.

Incidentally, you'll almost certainly see a much longer life if you
replace those 13W 1060lm lamps with the cheaper and brighter 12W 1520lm
Home Bargain lamps. Two reasons for longer life being 1 watt less input
power to start with and less of that energy being converted into waste
heat since more of it is used to generate light. In essence, a win-win
situation for a quarter of the original (or a sixth of the current) price
of those 13W LEDs you currently use.

[1] ISTR colour temperature options of 2700K and 6500K but I may be wrong
regarding the 2700K option, it might have been 3000K and there might also
have been a 4000K option which two options both tend to be more
acceptable by most than the extremes I quoted. You'll probably want to
avoid the 6500K (possibly 6000K) lamps as that tends to be a little too
'cool' for most people.

--
Johnny B Good