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Topic Title: Fanciful energy savings?
Topic Summary: Do domestic low energy devices actually help the planet?
Created On: 25 January 2009 04:56 PM
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 25 January 2009 04:56 PM
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JoanW

Posts: 21
Joined: 11 September 2001

In the UK, most of us spend most of our time in thermostatically controlled, heated accomodation. We only cool our rooms down for a very short part of the year.

So, if I replace all my incandescent lamps with 'low energy' flourescent ones and switch off my standby devices, how much energy do I actually save? After all, the 'waste' engergy of these devices is given off as low-grade heat which will simply be replaced by my thermostatically controlled central heating staying on for a few moments longer each day.

Or have I lost the plot somewhere?

Joan
MIEE etc

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JoanW
 31 January 2009 12:48 AM
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mmcgregor

Posts: 17
Joined: 20 March 2006

Joan,
You make a good point.
Not all, but some heating systems in large buildings are open loop. By that, I mean they can't be properly considered closed loop because the input measurement they use for temperature control is not the room temperature, but the heated air output temperature. So extra heat generated locally is not compensated for in the control loop. So users might notice the difference when low energy devices are used, and might turn up the thermostat manually.
Mike
BA etc.
 31 January 2009 02:21 PM
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westonpa

Posts: 1771
Joined: 10 October 2007

Originally posted by: JoanW

In the UK, most of us spend most of our time in thermostatically controlled, heated accomodation. We only cool our rooms down for a very short part of the year.

So, if I replace all my incandescent lamps with 'low energy' flourescent ones and switch off my standby devices, how much energy do I actually save? After all, the 'waste' engergy of these devices is given off as low-grade heat which will simply be replaced by my thermostatically controlled central heating staying on for a few moments longer each day.

Or have I lost the plot somewhere?

Joan

MIEE etc


No you have not lost the plot.

Regards.
 31 January 2009 07:58 PM
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ectophile

Posts: 529
Joined: 17 September 2001

I don't need any heating for a substantial proportion of the year. During that time, the heat from lamps is simply wasted. In any case, using standard tariff electricity for room heating is pretty expensive when compared with gas central heating.

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S P Barker BSc PhD MIET
 05 March 2009 06:23 PM
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Rock639

Posts: 14
Joined: 26 May 2008

Originally posted by: g3xoi

Joan,



One is tempted to say "I really do not see the Emperor's new clothes!"



You are absolutely correct.



Anything we, humans, do is dwarfed by volcanic activity, the eccentricity of the earth's orbit and its tilt, to say nothing of the effluent, both gaseous and thermal, from domestic beasts.



I do not even begin to enter the hot air spouted by our parliament and guardianistas!


However, that doesn't mean that we should add to any existing polution by contributing with our own. The planet does create its own polution, ie from volcanic activity or inhabitants natural gases, but this is balanced by nature. What we are contributing in polution may be enough to "tip the balance".

Is there evidence to prove that natural polution dwarfs that of mankind? If so, by how much?
 06 March 2009 09:26 AM
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sedgwicknc

Posts: 107
Joined: 20 October 2001

Specially for Rock639.

Is there evidence to prove that manmade polution dwarfs that of nature? If so, by how much?

Best regards

-------------------------
sedgwicknc
 06 March 2009 09:51 AM
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sedgwicknc

Posts: 107
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Originally posted by: ectophile

I don't need any heating for a substantial proportion of the year. During that time, the heat from lamps is simply wasted. In any case, using standard tariff electricity for room heating is pretty expensive when compared with gas central heating.


Both ectophile and Joan are right.

The real questions are about how much, the totality of benefit to change what we do (including all costs of the change), and particularly whether the suggested change involves a lost opportunity cost that means we don't do something even better.

Then there is the question of whether the benefit is one of saving money (spent on energy) or saving the planet.

Personally, I only see the former. As it's my money, I would like to be able to spend it as I chose. I use quite a number of Compact Fluorescent Lamps (CFLs) but also retain several incandescent ones. This is all for good reason, relating to cost, size, orientation of fittings (affects cooling of CFLs), convenience, and that most or many CFLs do not work properly with already fitted dimmers and timers. I'm also looking at the possibility of LED residential illumination, as these are even more efficient; however, my current view is that there is some way to go on spectral balance and cost.

Yesterday my last 150W incandescent bulb blew. It has not been possible (or is that just easy) to buy replacements for some time. Nor have I yet found a replacement CFL of equivalent illumination. The room requires the equivalent of 150W incandescent; why must I change the fittings to be able to mount 3x60W equivalents (or similar) rather than just being allowed to carry on as before, for this one light in a utility room, that is never switched on except when someone is in there and needing the illumination to look at things?

The government (EU and UK) has gone barmy trying to make the world perfect (though just 'their perfection'). In doing this and many similar things, it has lost the plot. The world economy is crumbling (not least through excessive attempts at wealth redistribution), the UK looks to be approaching failure to generate enough electricity for its needs, and so on.

Best regards

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sedgwicknc
 06 March 2009 01:28 PM
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ectophile

Posts: 529
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I find that halogen lamps are good alternative to conventional ones where you can't use, or don't want, a CFL. Watt-for-watt, they are brighter than standard incandescent lamps.

I have a 100W halogen on a dimmer in the living room, which works well in a glass shade. When the 60W bathroom lamp blew recently, I replaced it with a 40W halogen, and was quite pleased with the result.

You may have to do some hunting around to find them. I've got a small stash of the 100W ones, bought from a DIY store, just in case the EU decides to ban them.

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S P Barker BSc PhD MIET
 11 March 2009 05:33 PM
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Rock639

Posts: 14
Joined: 26 May 2008

Originally posted by: sedgwicknc

Specially for Rock639.



Is there evidence to prove that manmade polution dwarfs that of nature? If so, by how much?



Best regards


To be honest, my original question could / should have been put both ways. Either way, I don't believe (although I may be wrong!) that any completely independant evidence for either case exists...
 20 August 2009 08:36 AM
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koshkoro

Posts: 1
Joined: 20 August 2009

It's not realistic to expect there to be hard evidence of how much man versus nature's pollution rival each other. That both are growing at an alarming rate is what's at stake.

Joe Almirantearena
Link removed

-------------------------
California Home Loans

Edited: 27 August 2009 at 11:54 PM by koshkoro
 22 September 2009 12:14 PM
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OMS

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Interesting that those who claim to be measuring these things report a reduction in emmissions over the last year principally due to the economic downturn.

Who would have thought that the financial sector (not reknowned for thier "green credentials" ) would eventually be cast as the saviour of the planet - clearly they are not all merchant bankers then

Regards

OMS

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Failure is always an option
 24 October 2009 04:08 AM
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michaelward

Posts: 26
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JoanW you have to think of where these lights are situated, most being on the ceiling so give very little benefit as regards adding to the total heat of a room. Even a bedside light does not give off enough heat to warrant you worrying about the difference between a CFL and an Incandescent, other than purely on power used.

sedgwicknc
Get a daylight lamp for that room, and you will not have any problems, the light intensity put out will be greater than a 150W incandescent anyhow.

I would like to point out, that although halogen lamps are bright, they are not that efficient as regard power, most being driven through pretty wasteful (in power terms) transformers, and give off a lot of heat.
 26 October 2009 11:03 AM
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stevenprentice

Posts: 25
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I'll just add a couple of thoughts here.

Low energy fittings replace high energy fittings, say 12w replaces 60w or whatever and if you believe the manufacturers they give out the same light levels.

So, and I may be wrong here but my sums say that with conventional fittings there is 48W of energy going ... somewhere.... (as heat). Say I have 5 light fittings replaced, then te house isn't heated by (5x48) 240W of energy, or is this too simple a way of looking at it?

Now as for when I need the heat, generally it gets colder when it is dark outside - exactly the time I put my lights on.

I think that they do have an effect but not perhaps a great an effect as you might think.


Oh, I once read - on the subject of electricity efficiency - that all the toast we make in the morning could power a city the size of Birmingham. 2 options here - don't eat toast or turn of Birmingham and we can eat all the toast that we want.
 27 October 2009 07:26 PM
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michaelward

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You shouldn't use Wattage as a comparison, and a lot of people who sell these, make this mistake. It is the lumen output of the light which is important. You also have to look at the difference in efficiency of these lights to do a fair comparison. As far as heat is concerned, even CFL's give off heat and some are not supposed to wok in recessed sockets or hung, because the heat will shorten the bulb life, by destroying the ballast.

Typical efficiency for an incandescent at 100W is around 2.6% and a CFL is around 17% ( read that somewhere ). So if you want to calculate the difference in heat loss you would have to take into account the difference in efficiency, so the figure you have given is mistaken. Note, halogen is around 3.5% efficient.

Biggest difference will be in the wavelength of light given off by these devices, an incandescent goes more towards the infra-red part of the spectrum, whereas modern CFL and LED is higher up the frequency band.

Just as a side note, daylight bulbs are created by filtering out low spectrum light by adding a coating to the glass envelope, so that higher spectrum light is seen, which of course reduces the overall efficiency of the CFL, although this is compensated for by increasing its power consumption.
 21 November 2009 08:59 PM
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cmatheson

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What about a realistic view of what the impact the WEEE directive has now with used CFL's being takem to the disposal point?

Yes, the quantity of mercury is miniscule and what is the environmental cost of the disposal of a CFL lamp?

The way I see it though is that for too long now governments have kept their heads in the sand over the environmental impact of of our economy. Now some action is being taken. We are now finding out that, short of going back to a mideaval existence, the problems are multifaceted and the solutions not so easy but we will get there.......probably after the next ice age at this rate though!

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Chris Matheson MInstMC
 10 December 2009 05:22 PM
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JoanW

Posts: 21
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I've usually enjoyed the BBC's Bang Goes The Theory series and have just watched the Human Power Station edition via iPlayer. I enjoyed the game but notice that they sidestepped the domestic heating issue.

Joan

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JoanW
 10 December 2009 09:41 PM
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westonpa

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Joan,

You may well be an educated person and critically discuss and/or challenge what governments and some scientists say but 99% of the population do not....no disrespect to them of course.

You initial point is correct and also many offices nowadays have heating/cooling all year round.....let's see what happens when someone tries to turn that off!

Basically all this stuff is about providing people with a new purpose because things had got a little too stable. The purpose now is 'save the planet'. Did you ever see that film with Kevin Costner called Waterworld? Crap film but the point is there was a scene where all these people in an old oil tanker were rowing in some direction and the guy in charge was asked, by his 2nd in command, if he knew where they were heading. He said something to the effect "it does not matter because they will row for days before they realise I do not know where we are going".

Welcome to humanity.....row to save the world.

Regards.
 14 December 2009 12:31 PM
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oneye

Posts: 158
Joined: 25 February 2008

There was short article on the radio last night that discussed CFL's ...

The first point was dim for the first few minutes. That is something you get used to; although having an outside light I notice takes longer due to the lower ambient temperature. Having said that, there is less heat loss from the previous 100w that the CFL replaced.

The programme went on to discuss what was stated in the 1st post.
It even went on to discuss power factor which is not generally thought about, as CFL's need more current per watt making them less efficient than rated.

Edited: 14 December 2009 at 03:08 PM by oneye
 14 December 2009 08:06 PM
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westonpa

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Originally posted by: oneye

There was short article on the radio last night that discussed CFL's ...

The first point was dim for the first few minutes. That is something you get used to; although having an outside light I notice takes longer due to the lower ambient temperature. Having said that, there is less heat loss from the previous 100w that the CFL replaced.

The programme went on to discuss what was stated in the 1st post.

It even went on to discuss power factor which is not generally thought about, as CFL's need more current per watt making them less efficient than rated.


Try this http://news.bbc.co.uk/1/hi/magazine/8406923.stm

Regards.
 15 December 2009 02:13 PM
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oneye

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Joined: 25 February 2008

That's most of the content except radio had the odd interview ..
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