On Wed, 9 Jan 2008 20:33:08 +0100 someone who may be David in
Normandy wrote this:-

I've been disappointed with low energy bulbs. They
don't seem to last any longer than ordinary filament bulbs

They do in the houses I look after. Perhaps there is something with
your electricity supply, or you are getting the lamps from a
supermarket.



--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

Alternatively, make your own 162W compact fluorescent...
http://www.emanator.demon.co.uk/bigclive/hamster.htm

While that is impeccably DIY, I wish I could buy the 2 to 1 BC adapters
I grew up on. I promise I would use them only for CFLs and not these
days for the toaster, kettle, etc.

I have failed to find them by searching the net (and looking in stores
in France and the USA) so ask if the expert and eagle-eyed here know
where they (or similar ES adapters) are still available? Some
unreconstituted country perhaps? Car boot sales??

--
Robin

In an earlier contribution to this discussion,
neverwas wrote:

Alternatively, make your own 162W compact fluorescent...
http://www.emanator.demon.co.uk/bigclive/hamster.htm

While that is impeccably DIY, I wish I could buy the 2 to 1 BC
adapters I grew up on. I promise I would use them only for CFLs and
not these days for the toaster, kettle, etc.

Yes, I remember those - but haven't seen one for years. When I was a kid we
had one in the livingroom light socket - with a bulb in the (switched, I
think) straight ahead outlet and a bayonet adapter in the unswitched side
outlet with a flex going across the ceiling, round the picture rail, and
down to the steam radio.

I think the iron must have been powered off a similar one in the kitchen -
'cos we didn't have any power points until we got our first (one bar)
electric fire, and had to have one (round pin, 15A) specially installed.

Those were the days! g
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

Is one problem with CFLs the fact that most light comes from the sides - an
incandescent bulb probably (due to the filament location)pushes most light
up and down (relative to the cap)

On Thu, 10 Jan 2008 09:45:31 +0000, Dynamo Hansen
wrote:

I assume it's more - so is there a real net /overall/
saving over the bulb life?

The people who have studied these things in detail say so and I
believe them.

Oh well if *They* say so and *you* believe them.

*That's it then*

If you want to look at the figures try using a search
engine to study them.

Or alternatively ask on uk.d-i-y .

DG

On Thu, 10 Jan 2008 11:10:08 GMT someone who may be "John"
wrote this:-

Is one problem with CFLs the fact that most light comes from the sides - an
incandescent bulb probably (due to the filament location)pushes most light
up and down (relative to the cap)

I think that would only be a particular problem to someone trying to
design one to produce a narrow beam of light. It would be difficult
to design a mirror to do that. Wide beams are no problem and are
also rather more useful in lighting houses.



--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

On Jan 9, 8:10*pm, "Mark" wrote:
"Mark" wrote in message

...

I'll keep an eye open for higher wattage ones then. I don't
think I've ever seen ones higher than 20 / 22 watt.

Are the 27 watt ones the same size or larger?
--
David in Normandy

I've found these 60watt, equivant to 300 watt tungsten.

How much? king hell!

oops! Forgot the link. Here it is:-

http://www.lightbulbs-direct.com/var...l.asp?var=4119


They would be great, but they cost £47 EACH!!!!

Robert

"David Hansen" wrote in message
...
On Wed, 9 Jan 2008 20:33:08 +0100 someone who may be David in
Normandy wrote this:-

I've been disappointed with low energy bulbs. They
don't seem to last any longer than ordinary filament bulbs

They do in the houses I look after. Perhaps there is something with
your electricity supply, or you are getting the lamps from a
supermarket.

They do in our house too. We mark each one with the date of start of use and
the source when we put them in a holder. Of course that doesn't measure the
number of hours used but we've found that they do last for many years. We've
been replacing our conventional lamps with them for years.

Halogens don't perform well.

Our latest experiments are with LEDS, so far we're very please but it's
early days.

Mary

wrote in message
...
On 9 Jan, 20:04, "Mary Fisher" wrote:
"Roger Mills" wrote in message

...

...



Even if he is, it's a very valid question - and one that seems to be
ignored by the government when thrusting these token green measures on
us.
Just as your average suburban domestic windmill will take more energy
to
manufacture it than it will ever generate in its lifetime.

Evidence?



Well you could try asking someone who's got one.

An owner doesn't usually know the energy cost of manufacture.

The trouble is there
is nowhere near enough wind in most urban/suburban settings. It's a
bit old hat - even the most credulous innumerate greenies now accept
they don't work where there are trees and buildings.

Nobody is thrusting windmills on anyone.

We considered one and when we asked a supplier we were told honestly that
our suburban situation was unsuitable. We assumed that they were being
honest so I refer others to them.

Mary

"Roger Mills" wrote in message
...
In an earlier contribution to this discussion,
Mary Fisher wrote:

"Roger Mills" wrote in message
...

...

Even if he is, it's a very valid question - and one that seems to be
ignored by the government when thrusting these token green measures
on us. Just as your average suburban domestic windmill will take
more energy to manufacture it than it will ever generate in its
lifetime.

Evidence?

Tom Harrigan has kindly supplied that by the bucketful - saving me looking
up the references.


I've not yet found a low energy light bulb which comes anywhere near
the claimed tungsten equivalent for light output.

Do you just have one tungsten bulb per room?

Mary

No of course not. But if I can't replace tungsten with low energy on a one
for one basis, I'll have to install a lot more lighting points which -
quite apart from any cost and Part-P inplications - will spoil the look of
many of my rooms.

So the look of your rooms is more iomportant than the future of the
environment and your power bills.

It's your choice.

Some rooms have low voltage halogen downlighters. What am I supposed to
replace *those* with?

There's no 'supposed' about it.

I wouldn't have them anywhere but it's about personal taste.

Mary

In article ,
"Mary Fisher" writes:

"David Hansen" wrote in message
...
On Wed, 9 Jan 2008 20:33:08 +0100 someone who may be David in
Normandy wrote this:-

I've been disappointed with low energy bulbs. They
don't seem to last any longer than ordinary filament bulbs

They do in the houses I look after. Perhaps there is something with
your electricity supply, or you are getting the lamps from a
supermarket.

They do in our house too. We mark each one with the date of start of use and
the source when we put them in a holder. Of course that doesn't measure the
number of hours used but we've found that they do last for many years. We've
been replacing our conventional lamps with them for years.

Most of the ones I've bought have lasted too long -- i.e. they
have well exceeded their rated life and carried on working after
I should have replaced them (which is an issue as they don't
always die at end of life in the way we have come to expect of
other lamps, just get dimmer). These are mostly well know major
name ones, plus a load of IKEA ones I bought 7+ years ago which
just go on forever.

I've had a few which have had unacceptably short lives. These
have been no-name (or unheard-of-name), where I've had to search
for something unusual in order to fit in a particular fitting.
Otherwise, I've avoided no-name ones.

Halogens don't perform well.

In what sense? They are only slightly better than regular filament
lamps in efficiency (more so the LV ones, although they're all too
commonly used in very inefficient lighting schemes).

Our latest experiments are with LEDS, so far we're very please but it's
early days.

That's amazing.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Si wrote:
In message , Peter Parry
writes
On Wed, 09 Jan 2008 18:49:23 GMT, Mike Scott
wrote:

Shame about the dimmers in other rooms
though: are there dimmable low-power lights around?

Sort of, but as you dim them the colour rendering, which isn't
particularly good to begin with, gets badly skewed and the resulting
output tends to be shifted towards the blue end of the spectrum
creating exactly the opposite effect to the one you want.

You presumably have measured this Peter. My human experience of dimming
my 70W CFL is that the colour balance is reddish when first switched on,
becomes more neutral as it warm up, and having got to temp' doesn't
change as it's dimmed.

The very best CFLs I have installed will at 17W just about match a 60W
ordinary bulb, but are nowhere near as good as a 50W halogen.


The 11W devices are practically useless.

I reckon at best a real life gain of 3:1 on energy.

If they don't pop in the first few months, they seem to last better than
bulbs, true. I have put them in a lot of places that are sub
critical..outside lights mainly.

Mary Fisher wrote:
"David Hansen" wrote in message
...
On Wed, 9 Jan 2008 20:33:08 +0100 someone who may be David in
Normandy wrote this:-

I've been disappointed with low energy bulbs. They
don't seem to last any longer than ordinary filament bulbs
They do in the houses I look after. Perhaps there is something with
your electricity supply, or you are getting the lamps from a
supermarket.

They do in our house too. We mark each one with the date of start of use and
the source when we put them in a holder. Of course that doesn't measure the
number of hours used but we've found that they do last for many years. We've
been replacing our conventional lamps with them for years.

Halogens don't perform well.


My LV stuff significantly outlasts the filament bulbs. The high usage
areas - corridors and kitchens - seem to last about 2 yeras. The low
usage stuff (toilets bathrooms) still hasn't had a replacement in 5-6
years. Whereas the 60watt conventional bulb in the lumiere in the other
bathroom has gone about once a year.

Mains halogens are as bad as candle bulbs, agreed..complete waste of space.

Our latest experiments are with LEDS, so far we're very please but it's
early days.


Theres other promising technologies around the corner..

Mary

Huge wrote:
....
I cannot believe you are criticising him for simply asking for help in
obtaining the knowledge he needs to make an informed choice.

That's because the use of these things is a religious matter, not a technical
one. If you question religious orthodoxy, expect the Spanish Inquisition.


Nobody expects......

Sorry, couldn't resist. :-)


Judging by the various responses in the thread, the information isn't to
hand. But thanks anyway to all. If I ever find out, I'll post the info.


--
Mike Scott (unet at scottsonline.org.uk)
Harlow Essex England

On Thu, 10 Jan 2008 11:42:53 +0000 someone who may be Derek Geldard
wrote this:-

I assume it's more - so is there a real net /overall/
saving over the bulb life?

The people who have studied these things in detail say so and I
believe them.

Oh well if *They* say so and *you* believe them.

I looked into the subject in some detail at the time. Nothing has
been brought to my attention that implies things have changed
materially since then.

I don't carry the detailed discussions round in my head. If I wanted
to look them up I would start with a search engine.



--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

David Hansen wrote:
On Thu, 10 Jan 2008 11:42:53 +0000 someone who may be Derek Geldard
wrote this:-

I assume it's more - so is there a real net /overall/
saving over the bulb life?
The people who have studied these things in detail say so and I
believe them.
Oh well if *They* say so and *you* believe them.

I looked into the subject in some detail at the time. Nothing has
been brought to my attention that implies things have changed
materially since then.

I don't carry the detailed discussions round in my head. If I wanted
to look them up I would start with a search engine.



I am fairly sure that yes, CFLS do save energy. The real question is how
much, is it relevant, and are the disadvantages worth it?

My own personal opinion is that the answers a-

Not very much
Its not hugely relevant
In many cases the disadvantages are NOT worth it.

I use the things because in many case they are adequate, and work out
slightly cheaper in the long run.

However the main reason I use them is the longer bulb life. Its a pain
to keep replacing bulbs. Particularly in the lanterns outside the doors.

On Wed, 09 Jan 2008 16:44:27 +0000, Mike Scott wrote:

I'm curious. "Low energy" bulbs are very much in the news - but how much
extra energy is expended in their manufacture compared to a standard
incandescent? I assume it's more - so is there a real net /overall/
saving over the bulb life? If so, how much?


I don't think your question is actually answered here, but this page
gives a lot of info: http://sound.westhost.com/articles/incandescent.htm

One estimate is about 1kWh to manufacture a GLS and over 4 kWh for a CFL!
That is without taking end-of-life disposal into consideration.

It also looks as if, to get the same light output as a GLS, you really
need to choose a FCL that's "one size up" than the stated size, so use a
30W to get the equivalent of a 100W incandescent. Then the poor power
factor power factor of CFLs comes into it, and the power station has to
generate 60W to light your 30W CFL (although you are only charged for
30W). OK, it's an overall saving of 30%, but not as much as it initially
looks. You do get to have slightly cheaper bills though. :-)

--
Mick (Working in a M$-free zone!)
Web: http://www.nascom.info http://mixpix.batcave.net

In an earlier contribution to this discussion,
Mary Fisher wrote:

"Roger Mills" wrote in message
...

Some rooms have low voltage halogen downlighters. What am I supposed
to replace *those* with?

There's no 'supposed' about it.


OK, so what *is* the situation? If these are to be banned, the 'powers that
be' have *hopefully* thought about a suitable replacement which doesn't
involve demolishing and re-building my house?

I don't currently know what that is - although LED-based lights do look
reasonably promising.

I'm all for saving the planet, and reducing my fuel bills - honest - but
virtually every measure introduced by New Labour has been far more effective
at grabbing headlines than at achieving any real results. This has left me
cynical enough to suspect that banning the sale of conventional light bulbs
is yet another such measure.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

"Roger Mills" wrote in message
...
In an earlier contribution to this discussion,
Mary Fisher wrote:

"Roger Mills" wrote in message
...

Some rooms have low voltage halogen downlighters. What am I supposed
to replace *those* with?

There's no 'supposed' about it.


OK, so what *is* the situation? If these are to be banned, the 'powers
that be' have *hopefully* thought about a suitable replacement which
doesn't involve demolishing and re-building my house?

If the powers that be didn't enforce downlighting on you then they have no
responsibility to replace them.

I don't currently know what that is - although LED-based lights do look
reasonably promising.

I think so too. People dismiss them for their relatively (as yet) lopw light
emittance, their colour (which I like) and for other imagined problems but I
think they're the future. I might not be here to see it but I shan't be here
to see many other exciting things.

I'm all for saving the planet, and reducing my fuel bills - honest - but
virtually every measure introduced by New Labour has been far more
effective at grabbing headlines than at achieving any real results. This
has left me cynical enough to suspect that banning the sale of
conventional light bulbs is yet another such measure.

I don't like NL any more than anyone else and I agree that they go for
headlines but I don't think this matter is 100% theirs, it's going to come
through Europe (which is not liked either) or some other agency.

There are more important things to worry about though :-(

Mary
A greater cynic you couldn't find

On Jan 10, 12:22*pm, "Mary Fisher" wrote:
"Roger Mills" wrote in message

...





In an earlier contribution to this discussion,
Mary Fisher *wrote:

"Roger Mills" wrote in message
...

...

Even if he is, it's a very valid question - and one that seems to be
ignored by the government when thrusting these token green measures
on us. Just as your average suburban domestic windmill will take
more energy to manufacture it than it will ever generate in its
lifetime.

Evidence?

Tom Harrigan has kindly supplied that by the bucketful - saving me looking
up the references.

I've not yet found a low energy light bulb which comes anywhere near
the claimed tungsten equivalent for light output.

Do you just have one tungsten bulb per room?

Mary

No of course not. But if I can't replace tungsten with low energy on a one
for one basis, I'll have to install a lot more lighting points which -
quite apart from any cost and Part-P inplications - will spoil the look of
many of my rooms.

So the look of your rooms is more iomportant than the future of the
environment and your power bills.

The environment will suffer far more from the dumping of end of life
CFLs and all they contain, than a bit of tungsten, glass and some
inert gas.

MBQ

On Jan 10, 12:28*am, "OG" wrote:
"The Medway Handyman" wrote in nder.co.uk... Mike Scott wrote:
I'm curious. "Low energy" bulbs are very much in the news - but how
much extra energy is expended in their manufacture compared to a
standard incandescent? I assume it's more - so is there a real net
/overall/ saving over the bulb life? If so, how much?

Assuming that low energy bulbs are more efficient & give off less heat for
a given amount of light, would you not have to replace that heat in order
to maintain the same room temperature?

Yes but

No buts about it.

If your room needs heating, use a heater and put it where the heat needs to
be. It's madly inefficient to put a heater about 10 inches from the ceiling

Why? Give us the science.

(which is in effect what you are doing with incandescent bulbs).

Where do you think the air warmed by a heater ends up? If there's
already warm air there because it's been warmed by a bulb, what
happens to the heat from the heater? Think of the bulb as providing
the heat that would anyway dissipate through the ceiling to save the
heater from having to do it.

Same applies to TVs on standby.

MBQ

Man at B&Q wrote:
On Jan 10, 12:28�am, "OG" wrote:
"The Medway Handyman" wrote in nder.co.uk... Mike Scott wrote:
I'm curious. "Low energy" bulbs are very much in the news - but how
much extra energy is expended in their manufacture compared to a
standard incandescent? I assume it's more - so is there a real net
/overall/ saving over the bulb life? If so, how much?
Assuming that low energy bulbs are more efficient & give off less heat for
a given amount of light, would you not have to replace that heat in order
to maintain the same room temperature?
Yes but

No buts about it.

If your room needs heating, use a heater and put it where the heat needs to
be. It's madly inefficient to put a heater about 10 inches from the ceiling

Why? Give us the science.

(which is in effect what you are doing with incandescent bulbs).

Where do you think the air warmed by a heater ends up? If there's
already warm air there because it's been warmed by a bulb, what
happens to the heat from the heater? Think of the bulb as providing
the heat that would anyway dissipate through the ceiling to save the
heater from having to do it.

Same applies to TVs on standby.

MBQ


Anyway, its all ********. With enough nuclear power stations we can all
use incandescent bulbs to heat our houses without feeling guilty about it.

There is no *energy* shortage, just a fossil fuel shortage. And s
shortage of stuff upstairs in many peoples heas, and an overabundance of
money in certain industrial sectors that can see the writing on the
wakll and want to erase it before everyone else sees it.

The message
from The Natural Philosopher contains these words:

Whereas the 60watt conventional bulb in the lumiere in the other
bathroom has gone about once a year.

I have a 3 bulb enclosed fitting in my living room that used to eat
conventional bulbs at the rate of several a month. (Horizontal bulb
holders to add to the enclosed problem)*. Since switching to CFLs I have
had very few failures. Last one was last year and I think the date on it
was circa 2001. The 3 bulbs in at present are 2 off 11 watt dated 8/8/07
and 1/3/06 and 1 off 13 watt dated 21/9/03. I don't think that last one
will last much longer as the tubes are rather blackened.

*As my ceiling height is only about 6' 8" I am a bit limited in the type
of light fitting I can use and as I have small windows the light gets
switched on a lot more than your average sitting room light. The fitting
in question is a bit of a family heirloom having originally been one of
a pair installed in the new build family home in 1953 or 4 and moved to
my parents retirement bungalow in 1968. After my BiL broke one of the
covers changing a bulb the surviving example was passed on to me.
Funnily enough I don't recall these light fittings eating bulbs when I
was a child but perhaps bulbs were tougher then or more likely it is a
memory that hasn't survived the test of time.

--
Roger Chapman

The message
from Huge contains these words:

BTW, we went to India for a 2 week holiday a couple of months ago, and
didn't
see a single filament bulb the whole time - all the lighting in hotels,
restaurants, etc., was CFLs. I have no idea what that means.

Even when the wages are low it still costs labour to replace dud bulbs?

--
Roger Chapman

On 2008-01-10, Mary Fisher wrote:

"Roger Mills" wrote in message
...
[snip]

Some rooms have low voltage halogen downlighters. What am I supposed to
replace *those* with?

If they're MR16s, then there are 3 and 4W LEDS available (search for
Brilux/Luxeon/Cree MR16)


There's no 'supposed' about it.

I wouldn't have them anywhere but it's about personal taste.

Mary



I've been trying 3W and 4W 230V GU10 LED lamps. I like the cool/soft
white (6500K?) ones. However, although the LEDs may have an expected
life of 20- to 50,000 hours, the switched mode? PSUs in the bases of 3
out of the 8 I've been using have gone pop in less than the year I've
been using them for. (Several hours a day, can't be more specific.
2 of the failures were out of 4 from Initial Lights
http://www.initiallights.co.uk)

The others came from Hong Kong via eBay:
http://stores.ebay.com.hk/ledlightinghouse 1 failure out of 2

My suspicion that these are power supply failures comes not only from
hearing one go 'pop', but from experience with high powered LED cycle
lights which seem to be indestructable.

I've also tried and liked very much the cold cathode GU10s that Initial
Lights used to sell. These aren't direct replacements as you have
to connect them to a 500V high frequency power supply. They need a
minute or so to achieve full brightness, but the light that these 5W
bulbs produce is excellent - I have used them to illuminate framed prints.

--
Jan

On 10 Jan, 12:20, "Mary Fisher" wrote:
wrote in message

...



On 9 Jan, 20:04, "Mary Fisher" wrote:
"Roger Mills" wrote in message

...

...

Even if he is, it's a very valid question - and one that seems to be
ignored by the government when thrusting these token green measures on
us.
Just as your average suburban domestic windmill will take more energy
to
manufacture it than it will ever generate in its lifetime.

Evidence?

Well you could try asking someone who's got one.

An owner doesn't usually know the energy cost of manufacture.


It is a difficult question to answer. For my own purposes, I assume
10% of the final cost to me, unless the item is manufactured in an
economy where energy and labour is cheap, where I assume 20%. So, a
1000ukp turbine will have to produce 200ukp of electricity, or 2000kWh
of electricity before it fails to energetically pay for its
manufacture. At 5 quid a year, not very likely.

The trouble is there
is nowhere near enough wind in most urban/suburban settings. It's a
bit old hat - even the most credulous innumerate greenies now accept
they don't work where there are trees and buildings.

Nobody is thrusting windmills on anyone.


I don't agree. The grants available, the extra points on your home
energy assessment, the example set by our betters (eg David Cameron),
domestic generation inducements from electricity suppliers etc. add up
to a very strong encouragement bordering on coercion.

I do plan to install one however, especially if I can get the taxpayer
to pay for part of it.

T

On 2008-01-10 15:01:22 +0000, Huge said:

On 2008-01-10, The Natural Philosopher wrote:

My own personal opinion is that the answers a-

Not very much
Its not hugely relevant
In many cases the disadvantages are NOT worth it.

Combine that with the enthusiasm displayed by the likes of Hansen, Mary and
Hilary Benn (and other similar innumerates), the fact that they don't actually
last as long as the manufacturers say and that some find the light and/or the
start-up time unacceptable, what other reasons do we need not to use them?

BTW, we went to India for a 2 week holiday a couple of months ago, and didn't
see a single filament bulb the whole time - all the lighting in hotels,
restaurants, etc., was CFLs. I have no idea what that means.

Exactly the same as the little notices about how much washing of towels
in hotels harms the environment. This of course has nothing to do
with any cost saving for the hotel at the expense of comfort for its
guests.

On 10 Jan, 15:26, "Man at B&Q" wrote:
On Jan 10, 12:22 pm, "Mary Fisher" wrote:



"Roger Mills" wrote in message

...

In an earlier contribution to this discussion,
Mary Fisher wrote:

"Roger Mills" wrote in message
...

...

Even if he is, it's a very valid question - and one that seems to be
ignored by the government when thrusting these token green measures
on us. Just as your average suburban domestic windmill will take
more energy to manufacture it than it will ever generate in its
lifetime.

Evidence?

Tom Harrigan has kindly supplied that by the bucketful - saving me looking
up the references.

I've not yet found a low energy light bulb which comes anywhere near
the claimed tungsten equivalent for light output.

Do you just have one tungsten bulb per room?

Mary

No of course not. But if I can't replace tungsten with low energy on a one
for one basis, I'll have to install a lot more lighting points which -
quite apart from any cost and Part-P inplications - will spoil the look of
many of my rooms.

So the look of your rooms is more iomportant than the future of the
environment and your power bills.

The environment will suffer far more from the dumping of end of life
CFLs and all they contain, than a bit of tungsten, glass and some
inert gas.

MBQ

I think this is precisely the point. A proper analysis and comparison
of the whole life costs of the different bulb technologies has not
been done. We shouldn't rely on manufacturer's claims for such a study
either. We could simply be supplanting energy use here for even more
use in China. We are certainly embarking on increased mercury
pollution- and what are the environmental and health costs of that,
not to mention the other health risks of cfls in the news recently.

T

"RobertL" wrote in message
...
On Jan 9, 8:10 pm, "Mark" wrote:
"Mark" wrote in message

...

I'll keep an eye open for higher wattage ones then. I don't
think I've ever seen ones higher than 20 / 22 watt.

Are the 27 watt ones the same size or larger?
--
David in Normandy

I've found these 60watt, equivant to 300 watt tungsten.

How much? king hell!

oops! Forgot the link. Here it is:-

http://www.lightbulbs-direct.com/var...l.asp?var=4119


They would be great, but they cost £47 EACH!!!!

Robert


You forgot the VAT so they cost £55.86 each.
A mere £50 each if you buy 10.

mark

In an earlier contribution to this discussion,
Jan Wysocki wrote:

"Roger Mills" wrote in message
...
[snip]


Some rooms have low voltage halogen downlighters. What am I
supposed to replace *those* with?


If they're MR16s, then there are 3 and 4W LEDS available (search for
Brilux/Luxeon/Cree MR16)


Interesting - but still a long way to go!

The 4 watt bulbs claim to be equivalent to 20 watt halogens. I have 12 (3
banks of 4) 50 watt halogen downlighters in my lounge. Twelve 4W LEDs (at
£16 a throw!) ain't going to get me very far.

Also, while they may be plug compatible, they're unlikely to work with my
existing transformers - since these require a sizeable minimum load before
they operate.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

In article ,
writes:
We are certainly embarking on increased mercury pollution

No we aren't.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

I've a couple of switched ones somewhere, and a triple. The double
ones would
be useful where 20w cfls arent quite enough.

Any for sale pl?

--
Robin

wrote:
On 10 Jan, 12:20, "Mary Fisher" wrote:
wrote in message

...



On 9 Jan, 20:04, "Mary Fisher" wrote:
"Roger Mills" wrote in message
...
...
Even if he is, it's a very valid question - and one that seems to be
ignored by the government when thrusting these token green measures on
us.
Just as your average suburban domestic windmill will take more energy
to
manufacture it than it will ever generate in its lifetime.
Evidence?
Well you could try asking someone who's got one.
An owner doesn't usually know the energy cost of manufacture.


It is a difficult question to answer. For my own purposes, I assume
10% of the final cost to me, unless the item is manufactured in an
economy where energy and labour is cheap, where I assume 20%. So, a
1000ukp turbine will have to produce 200ukp of electricity, or 2000kWh
of electricity before it fails to energetically pay for its
manufacture. At 5 quid a year, not very likely.

The trouble is there
is nowhere near enough wind in most urban/suburban settings. It's a
bit old hat - even the most credulous innumerate greenies now accept
they don't work where there are trees and buildings.
Nobody is thrusting windmills on anyone.


I don't agree. The grants available, the extra points on your home
energy assessment, the example set by our betters (eg David Cameron),
domestic generation inducements from electricity suppliers etc. add up
to a very strong encouragement bordering on coercion.


Ive just been listening to the beeb.

germany will pay you about twice what they will sell you electricity at,
if you make it from windmills or solar panels. MASSIVE susbify, since
its totally unecomonic.

Contrast the speches today with respect to nuclear. "Has to pay for
itself, no government subsidies".

Level playing field my arse.




I do plan to install one however, especially if I can get the taxpayer
to pay for part of it.

T

mick wrote:

[...] and the power station has to generate 60W to light your 30W CFL
(although you are only charged for 30W).

That's a complete misunderstanding of the idea of power factor. The
[supply system] doesn't have to generate 60 W, nor burn fuel at a rate
equivalent to 60 watts worth of output. The (RMS) current drawn by the
lamp is the same as for 60 W resistive load, so resistive losses in the
cables are increased by a factor of four without power factor
correction. However the I^2*R losses due to current drawn by your
lighting load will pale into insignificance compared to that caused by
much heavier resistive loads (cookers, heaters, showers).

OK, it's an overall saving of 30%, but not as much as it initially
looks. You do get to have slightly cheaper bills though. :-)

:-( 4:1 GLS:CFL is nearer the mark, so a ~75% saving in principle
(probably reduced in practice because you tend to leave them on longer).
Assuming a PF of 0.5 (some CFLs are actually lower than that) it's a 50%
reduction in current compared to GLS, so also a 75% reduction in I^2*R loss.

--
Andy

On 10 Jan, 20:07, (Andrew Gabriel) wrote:
In article ,
writes:

We are certainly embarking on increased mercury pollution

No we aren't.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Thank you for that illuminating reply. I don't quite understand why
you bother though. Surely any possible humour in your persistently
childish responses has worn thin by now? Or is that really the best
you can do? In which case you have my sympathy.

On 10 Jan, 21:16, The Natural Philosopher wrote:
wrote:
On 10 Jan, 12:20, "Mary Fisher" wrote:
wrote in message

...

On 9 Jan, 20:04, "Mary Fisher" wrote:
"Roger Mills" wrote in message
...
...
Even if he is, it's a very valid question - and one that seems to be
ignored by the government when thrusting these token green measures on
us.
Just as your average suburban domestic windmill will take more energy
to
manufacture it than it will ever generate in its lifetime.
Evidence?
Well you could try asking someone who's got one.
An owner doesn't usually know the energy cost of manufacture.

It is a difficult question to answer. For my own purposes, I assume
10% of the final cost to me, unless the item is manufactured in an
economy where energy and labour is cheap, where I assume 20%. So, a
1000ukp turbine will have to produce 200ukp of electricity, or 2000kWh
of electricity before it fails to energetically pay for its
manufacture. At 5 quid a year, not very likely.

The trouble is there
is nowhere near enough wind in most urban/suburban settings. It's a
bit old hat - even the most credulous innumerate greenies now accept
they don't work where there are trees and buildings.
Nobody is thrusting windmills on anyone.

I don't agree. The grants available, the extra points on your home
energy assessment, the example set by our betters (eg David Cameron),
domestic generation inducements from electricity suppliers etc. add up
to a very strong encouragement bordering on coercion.

Ive just been listening to the beeb.

germany will pay you about twice what they will sell you electricity at,
if you make it from windmills or solar panels. MASSIVE susbify, since
its totally unecomonic.

Contrast the speches today with respect to nuclear. "Has to pay for
itself, no government subsidies".

Level playing field my arse.


I sat open mouthed while watching the News at Ten tonight. With all
the spin on renewables we've endured over recent years, they finally
admitted what offshore wind costs - 85quid/MWh!!!

The figures they quoted we

Coal 30ukp/MWh
Gas 38ukp/MWh (and going up no doubt)
Nuclear 39ukp/MWh
Offshore Wind 85ukp/MWh

Some green energy companies will pay you based on what appears to be a
calculation (ie gross overestimate) of what your turbine might
produce. I note that Equipower will pay you 18p for every unit you
export vrom your solar panel! All this to get their hands on ROCs!

T

On Thu, 10 Jan 2008 22:54:21 +0000, Andy Wade wrote:

mick wrote:

[...] and the power station has to generate 60W to light your 30W CFL
(although you are only charged for 30W).

That's a complete misunderstanding of the idea of power factor. The
[supply system] doesn't have to generate 60 W, nor burn fuel at a rate
equivalent to 60 watts worth of output. The (RMS) current drawn by the
lamp is the same as for 60 W resistive load, so resistive losses in the
cables are increased by a factor of four without power factor
correction. However the I^2*R losses due to current drawn by your
lighting load will pale into insignificance compared to that caused by
much heavier resistive loads (cookers, heaters, showers).



You sure about that? I oversimplified.

For a poor PF load the voltage and current are out of phase with each
other (how far depends on the PF PF=1 is in phase, PF=0 is 90deg out).
The generator is producing (and consuming fuel for) VA (real power).
However, domestic consumers pay by W (apparent power), not VA. So you see
30W of load at the meter and can measure the AC RMS current into the
lamp, but the V and A waveforms are out of phase so the actual V*A is
greater than the W value. (W=VA*PF so a 30W (apparent power) lamp with a
PF of 0.5 will require 30/0.5=60VA input to power it)

Agreed that the distribution losses into poor PF loads also escalate with
I^2R.

Also agree that the % difference on your bill will be insignificant. :-)


--
Mick (Working in a M$-free zone!)
Web: http://www.nascom.info http://mixpix.batcave.net

In article ,
mick writes:

You sure about that? I oversimplified.

For a poor PF load the voltage and current are out of phase with each
other (how far depends on the PF PF=1 is in phase, PF=0 is 90deg out).
The generator is producing (and consuming fuel for) VA (real power).

It doesn't work like that. What's happening at the per mains cycle level
is that at one point in the cycle you are drawing more power than you
need, and at another point you are giving back the excess. The supply
infrastructure has to carry and be sized for this extra power you took
and then gave back (and weren't charged for) plus the power you actually
used, but all that happens is that someone else will use the power you
gave back and the generator doesn't need to produce it again for them.

However, the low power factor resulting from compact fluorescents
doesn't involve any significant phase shift. It results because the
power supply in the lamps only draws power in the peaks of the waveform.
This power draw only in the peak is stored in the lamp and used to
generate a continuous output. However, with supply losses being I^2R,
drawing twice the current for half the time still generates twice the
power loss in the supply infrastructure, although as Andy pointed out,
that's still less than the losses from an equivalent filament lamp.
But the power station in this case only has to generate the power for
the period of the cycle when the lamp draws it. Inertia of the
generator armatures smooths this out in practice.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

mick wrote:
On Thu, 10 Jan 2008 22:54:21 +0000, Andy Wade wrote:

mick wrote:

[...] and the power station has to generate 60W to light your 30W CFL
(although you are only charged for 30W).
That's a complete misunderstanding of the idea of power factor. The
[supply system] doesn't have to generate 60 W, nor burn fuel at a rate
equivalent to 60 watts worth of output. The (RMS) current drawn by the
lamp is the same as for 60 W resistive load, so resistive losses in the
cables are increased by a factor of four without power factor
correction. However the I^2*R losses due to current drawn by your
lighting load will pale into insignificance compared to that caused by
much heavier resistive loads (cookers, heaters, showers).



You sure about that? I oversimplified.

For a poor PF load the voltage and current are out of phase with each
other (how far depends on the PF PF=1 is in phase, PF=0 is 90deg out).
The generator is producing (and consuming fuel for) VA (real power).
However, domestic consumers pay by W (apparent power), not VA. So you see
30W of load at the meter and can measure the AC RMS current into the
lamp, but the V and A waveforms are out of phase so the actual V*A is
greater than the W value. (W=VA*PF so a 30W (apparent power) lamp with a
PF of 0.5 will require 30/0.5=60VA input to power it)

Agreed that the distribution losses into poor PF loads also escalate with
I^2R.

Also agree that the % difference on your bill will be insignificant. :-)


Substations have BANKS..ACRES of capacitors to correct for power factor,
so that the generators do NOT have to run widely differing VI phase
differences. Its not really clear what sort of PF a CFL is anyway..A
bridge rect and an electrolytic maybe? Or a half wave rect and an
electrolytic..I bet there is a lot of input ripple..its easy enough to
stabilise output ripple with an HF SMPS..anyway a bot of C across the
mains is good, as its in the reverse direction to all those motors and
things..there the current lags the voltage..with capacitors it tends to
lead a bit.

Andrew Gabriel wrote:
In article ,
mick writes:
You sure about that? I oversimplified.

For a poor PF load the voltage and current are out of phase with each
other (how far depends on the PF PF=1 is in phase, PF=0 is 90deg out).
The generator is producing (and consuming fuel for) VA (real power).

It doesn't work like that. What's happening at the per mains cycle level
is that at one point in the cycle you are drawing more power than you
need, and at another point you are giving back the excess. The supply
infrastructure has to carry and be sized for this extra power you took
and then gave back (and weren't charged for) plus the power you actually
used, but all that happens is that someone else will use the power you
gave back and the generator doesn't need to produce it again for them.

However, the low power factor resulting from compact fluorescents
doesn't involve any significant phase shift. It results because the
power supply in the lamps only draws power in the peaks of the waveform.
This power draw only in the peak is stored in the lamp and used to
generate a continuous output. However, with supply losses being I^2R,
drawing twice the current for half the time still generates twice the
power loss in the supply infrastructure, although as Andy pointed out,
that's still less than the losses from an equivalent filament lamp.
But the power station in this case only has to generate the power for
the period of the cycle when the lamp draws it. Inertia of the
generator armatures smooths this out in practice.

well the last statement is a bit specious, given the miles of inductive
line and the leakage inductance of all the transformers in between..