"R!" writes:

Seán O'Leathlóbhair wrote in
oups.com:

snip


I also have qualms about the overall value of these bulbs. They are
complex devices and I have not heard of any schemes for recycling or
safe disposal. It is very hard, as an end user, to judge the pros and
cons. From a selfish point of view, I can look at the cost to me.
The low energy bulbs cost considerably more. The hope is that the
longer lifetime and lower energy use compensate for this. The longer
lifetime seems to be linked to the physical size. The larger ones do
indeed seem to have a long life. The first ever ones I bought, about
15 years ago, are still working but they are huge by modern
standards. The larger of the newer ones have a good life time but I
have had a few failures. The small new ones, which are required for
some applications, seem to have a noticeably shorter life time. In
this case, is not so obvious that I am spending less on the bulbs than
on incandescent ones. Also, I find the energy saving not as great as
claimed. I usually don't find them as bright as the claimed
equivalents. I guess that the equivalence claims are true in some
sense but not in my subjective judgment. If I replace an incandescent
bulb with a low energy with the same claimed equivalent power, it
usually looks dimmer. I often have to buy one step up from the
claimed equivalent power and hence make a smaller saving. An
exception to this last point is the one that inspired this thread. It
actually seems brighter than the incandescent that it replaced despite
having the same claimed equivalent power. Of course, I have no idea
of the life time yet.

On the heating point that same raise. I am aware that the heat from
the incandescent bulbs will be slightly reducing the heat required
from other sources. However, even here in the UK, I am not running
the heating all the time, and electricity costs me more per joule than
gas. Even when using the heating, I like the cooler running of the
low energy bulbs, I hope that it reduces the fire risk in some of the
cramped places that bulbs are used. I have seen lamp shades scorched
quite worryingly by incandescent bulbs (even when within the stated
limits of the shade). I have never seen this with a low energy bulb.
Finally, not everyone lives in a cold country. I have a house in the
Philippines, there heating is unknown but air conditioning is
desirable. The stray heat from incandescent bulbs is a double waste
since it is increasing the load on the air conditioning.

I have dropped the long list of apparently irrelevant groups.

--
Seán Ó Leathlóbhair



I think CFL's just don't wash..

I have bought several in various price ranges...

The really cheep ones only last about 3 months...

The medium priced ones last about 1 year to 18 months.

The one I paid the most for has been going for about 5 years.

Based on this it only makes sense to buy the longest lasting ones...

At $22.00 US I could buy aproximately 88, 60W 120V lamps.

Which gives me 88,000 hours of light.

The life of the lamp that has lated five years was promoted at

30,000 hours...

So that makes the inital cost about 1.5 times as much as the standard
bulb.

Cost of 60W incandescent lamp: $0.25 cents.
Cost of electricity to run a 1000 hour 60W lamp over its life at 10
cents/kWh: $6.
Total cost over life: $6.25.

Cost of electricity and lamps to run 60W lamps over 30,000 hours: $187.50.

Cost of 60W equivalent CFL + electricity over 30,000 hours assuming it
uses 25 percent of the power of a 60 W incandescent lamp: $22 + $45 = $67.

Around here, good quality spiral CFLs with 5,000 to 8,000 hour claimed
lifetimes cost around $5-6 in hardware stores (much less at large home
centers).

But even at $6, a 60 W equivalent CFL just about pays for itself if it
only lasts slightly longer than one incandecent lamp. They typically
last much longer - guessing 2 or 3 years of normal use which is probably
close to their claimed 5,000 to 8,000 hour life.

I also use 2, 100w 120 lamps as a heat source to keep the water pipes
from freezing in really cold weather...

I haven't figured out a safer or more economical way to heat a 5' x 5'
pump house.

Now, if you're really using the waste heat of the incandescent lamp - which
accounts for around 95 percent of the power used - then the savings will
not be as great. But although resistance heating is 100 percent efficient
as far as conversion of power to heat is concerned, heat pumps and even
gas or oil ends up being cheaper.

Of course, if it's hot and you need to run the A/C, you're paying twice!

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