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Q: embodied energy in lighting equipment ( Answered 4 out of 5 stars,   6 Comments )
Subject: embodied energy in lighting equipment
Category: Science
Asked by: kevan_shaw-ga
List Price: $25.00
Posted: 21 Oct 2002 15:29 PDT
Expires: 20 Nov 2002 14:29 PST
Question ID: 86161
I am looking for any quantified information on the energy embodied in
lamps and lighting equipment in the materials used and manufacturing
process. I am also interested in any connected information relating to
the energy used in the installation of lighting equipment

Request for Question Clarification by hedgie-ga on 22 Oct 2002 03:43 PDT
        Can you clarify what you mean by 'embodied' ?
 Let's say for a lightbulb:
        Do you mean energy used to make a lightbulb 
        (including for example  heat neded to melt the glass?)

 or energy which is
        still 'in the bulb' when you buy it?

        It may help if you eleborate the goal,
        since one (technically correct) answer is this:

 for a light bulb, 1) determine its mass
                   2) multiply by c squared

          Result is total energy content of the bulb.

   I can supply actual numbers here, but doubt that that is
   what you are after. Or are you?


Clarification of Question by kevan_shaw-ga on 22 Oct 2002 09:35 PDT
I am looking for the energy used in its manufacture and also typical
for transport to place of use. I am reviewing the argument that low
energy use is an entirely valid measure for selection of lighting
equipment and also trying to quantify at what point it is valid to
replace older "non energy efficient" installations. My previous work
on this is on my website and I am
working towards an update of this paper. Thanks for your help on this

Subject: Re: embodied energy in lighting equipment
Answered By: hedgie-ga on 23 Oct 2002 11:38 PDT
Rated:4 out of 5 stars
Hello Kevin,
           Here are few links which contain numbers on savings in
  of monetary cost end environmental advantage of modern light
  From the environmental point of view, we do live at the era of
  transition from the incadescent lighting to more efficent CF light

    The environmental cost is not always exactly measured by the 
    purchasing cost, since some environmental loads do not show in the
    For example, CF lights may contain mercury - a  heavy metal, which
    want to avoid using and throwing out, even if we, as consumers, do
    immediately pay for that. But it is a good starting point.

 So, as a first aproximation of the impact on environment it is
reasonable to
 use the cost, the purchase price. First number we obtain on that is
that the
 cost of equipment is small, about 4% of the long term savings, when
we are
 switching fron incadescent to CF.  Here is one example:

Cost of retrofit
At Western Power, energy savings were 391,600 kWh/year with lighting
levels increasing around 37%. They had a simple payback period of 11.8
months with a cost of $32,000 and energy savingsof $32,400/year:

 Similar number come up, when we estimate cost of upgrade to modern
 For example, $4,000 a year in lamp replacement costs may add up to
$88,000 per
 year in electric energy costs. The exact ratio will depend on the
kind of lamps used and energy costs in the area. Example and
calculator toold are here:

 The saving apply not only to the light soirces but also to the
 To help consumers to get oriented in the complex and confusing world,
 US government (EPA and DOE) operate an energy star labeling program.
They say:

FACT:          ENERGY STAR labeled lighting uses up to 75% less energy
               standard lighting.  When you save energy, you not only
save money
               on utility bills, but you also protect our environment.
               For other tips
               and ways to change the world, download our 2-page
               Brochure for more information on choosing ENERGY STAR
               The fall lighting promotion is part of ENERGY STAR's

US Government is not just preaching but also doing that:

and evaluationg the saving and environmental benefits:

Some of those numbers are impressive:

     When just one room in every home is brightened by ENERGY STAR
 the change will keep over 1 trillion pounds of carbon dioxide out of
our air.  A typical household spends $90 a year, or 10% of its annual
bill, on lighting. ENERGY STAR labeled lighting costs less than half
as much as traditional models to operate.

  Coming back to energy cost of retrofit, here is that same question
posted in a discussion group:

"I'm less sure about the lifetime energy use of a CF relative
to its energy cost to manufacture, mainly because it uses such a small
amount of electricity. I'd still go with the compact fluorescent, in
of the real concern (mentioned by Mark Murray: "... watch all that
and all those resources ... get thrown into the environment ...")

 Conclusion seems to be here too, that cost and ecological load to
 manufacture is negligeable to saving of energy.

One disadvantage of CFs was lack of dimming and unnnatural colors:
 The technology advance eliminated color limitations:

and produced CFs with dimmer

So,  in conclusion, it would be possible to obtain breakdown of the
     manufacturing cost, but very complex. Cost of mining the ore, 
     producing the metal, cost of workers driving their cars to

     but it seems reasonable to estimate that by price. Not comparing
     price of one old bulb to one CF, but comparing total cost of
     by CFs to the old way.  The new way wins on all fronts:

Electricity savings translates into preventing pollution -
 for instance, the 275 million CFLs being used in North America
 at the start of 2000 will prevent 3.5 million tons of
carbon and 69000 tons of sulfur emissions this year. CFLs also reduce
energy bills. In Scandinavia, for example, a user can purchase a
high-quality CFL for 1.50 euros (~US$1.50) from the retailer Ikea.
Average residential electricity in Denmark is 0.13euros/kWh
($0.13/kWh), thus the payback on a lamp burning 4 hours per day is
reached in less than six months. Looking at bulb replacement and
electricity savings over the 10000-hour life of the lamp, a CFL has a
net present value of 49 euros (about $49) - 12 times the price of the

and so on

 The URL you mentioned gives 404 (not there) but I hope that the
 and examples given above will be useful to your argument.


Request for Answer Clarification by kevan_shaw-ga on 23 Oct 2002 12:38 PDT
I am afraid the answer skirts around the issue. I am looking for
something to confirm that the fluorescent solution IS environmentally
speaking cost neutral. here is another link to my argument
I really do want to find some numbers on the energy used in the
materials for not just lamps but fixtures as well as these need to be
changed. The numbers I previously created were based on info on raw
materials and guestimates for other elements, if there really is
nothing out there then someone is hiding something! Probably lamp and
fixture manuacturers who are gaining a lot of business convincing
people to replace non life expired equipment. Please see if you can
find anything more on embodied energy that would be applicable to the
lighting industry.

TIA, Kevan

Clarification of Answer by hedgie-ga on 24 Oct 2002 23:51 PDT
Hi again

        This new URL works and I was able to read your article and learn
about EMBODIED ENERGY as defined e.g. here:

  I can see that giving you the 'conventional wisdom' was not satisfactory,
  since your goal is to critically analyse such claim.

 I will try again. However, I doubt that scarcity of such data is due to
  conspiracy of manufacturers, which would have to include EPA and DOE.
It may be  possible to ask then to document their claim that switching to
CFL is environmentaly positive.
So, it may take some time to provide clarifaction. Please be patient.
In the meantime, can you please elucidate your sentence in paragraph 3:

I" t is unfortunate that issues of
 energy use are easily demonstrated in a numerical model which is neither
 available or desirable for the total impact of a lit environment on the Global
 Environment or for that matter on a human user"

 Are you saying there is an easy numericsl model?

 I can see and easy calculation for materials, for eaxmple Al, where energy
 used is a substatial part of the cost. I doubt there is a simple model for
 a light bulb or a light fixture, where cost of materials is small part of
the total price. 
 Do you agree that cost of the item provides an upper limit to the amount
 energy used in its production?

Request for Answer Clarification by kevan_shaw-ga on 25 Oct 2002 01:57 PDT
Yes I am saying an energy in use calculation is simple and convenient.
I was trying to expand the point by saying that energy use either
embodied or in use is only one area of Environmental concern. There
are issues of disposal, issues of the quality and nature of light for
human biology and psychology, isswues of light polution etc. etc. all
are conveniently swept under the carpet of energy in use which is all
too easy to quantify!

I am giving this paper or a modifed version on 7 November. This was
booked a while ago buc cancelled so I didn't get much done on it so
now I am in a bit of a panic to do something with it before I give it

Thanks for your help, I look forward to seeing if you can find
anything else

Kevan Shaw

Clarification of Answer by hedgie-ga on 25 Oct 2002 08:24 PDT
          this is a very interesting and important issue.

 I usually suspect 'campaigns' but I admit that I have never
 before questioned the 'advantages' of CFL. I see now that issue
 is more complex than I thougt. In my second search I was looking for
 'hard numbers' on the  'extended cost', which includes:
 1 direct energy use,
 2 selection of materials and equipment that minimise
 embodied energy
 3 allow for achieving a full useful life through ease of
 4 provide an optimum quality of light for the users of the space
 5 provide for re-use and recycling at end of life of the entire
  6 consider quantity and materials of lamps and light sources
consumed in
   the life of the installation

  I think that term 'imbedded energy' is more useful for
  materials, particularly materials used in bulk (such as
  building materials) than for fixtures, electronics...
    I do not see any evidence cost is intentionally hidden.
   It just is not easy to evaluate energy used in all hunreds
    of parts, chips, plastic boards etc.

    This university study says the key to retrofit planning is
  'proper disposal' of waste:
 (section with header
 Fluorescent Lamps  has 3 pdf reports).

    Here are the US federal rules on disposal of FL tubes:

     Both lighting upgrades and routine maintenance entail the removal
 of lamps and ballasts from the system. These lamps and ballasts must
 disposed of according to state and Federal regulations; if they
then the stricter regulations must be obeyed. Mercury-containing
and high-intensity discharge (HID) lamps and PCB-containing ballasts
are two
types of potentially hazardous waste.

    Cost of disposal:
  and here are data on ballast disposal (including PCB issue)
  and info from EPA :

  In this (commercial) calculation the extended cost is
  missing in calculation, but they have an paragraph on the
  disposal process improvement (low Hg, etc):

  Here are some numbers on mercury, ballast waste and new technology

  With such corrections, the cost of retrofit appears to be a good
  quantitative measure of environmental costs.
  I have find one (software) program which promises to calculate cost

 Apparently some companies are beginning to pay attention to cost
 of transportation and packaging:

 Here are some numers on cost installation:

 In conclusion:
                   It is not 'An Inexact Science'

 and many  aspects are a subject of current research:
 Research in EU

 and fast changing technology:

 Some numbers and references on efficacy can be obtained
 from case histories of retrofits and designs of energy efficient

     Lighting Makeovers: The Best Is Not Always the Brightest
    Kathryn M. Conway is the editor-in-chief at the Lighting
     Research Center at Rensselaer Polytechnic Institute in Troy, New
York. She co-authored The Lighting Pattern Book for Homes
     from which this article is adapted.

Here is a  case history where cost reported is:
The total average unit cost, including labor, material, permitting
 and management was $48.23 per
 fixture. They offer more info by e-mail.

 Studies of retrofit which promise to evaluate full costs

  Case history of a new building striving to reduce the embodied
   energy (may contain specific numbers and ideas)

more on the electronic ballasts (DIMMABLE)

       This is a complex issue, which indeed requires a professional
       of an experienced designer.
       I am glad that people like you are analysing
       these issues and hope that some of the references shown may
       useful numbers.
       If and when I get answers from some queries I made, I will post
       more clarification.
       Since time is at premium, I am posting this partial
       list of references for your perusal.


Request for Answer Clarification by kevan_shaw-ga on 25 Oct 2002 15:20 PDT
Thanks for this it certainly gives me somethin to work on this weekend!


Clarification of Answer by hedgie-ga on 27 Nov 2002 06:35 PST
Hello Kevin, 

               I hope your presentation went well.
  This  'clarification'  is needed to close the question.

kevan_shaw-ga rated this answer:4 out of 5 stars and gave an additional tip of: $20.00
Difficult issue, researcher was persistant in looking for a good answer!

Subject: Re: embodied energy in lighting equipment
From: neilzero-ga on 29 Oct 2002 10:35 PST
Since you are likely one of the world's formost experts, if you have
no other adgenda than what is best for our planet, I probably can't
add anything you don't know. Determining the long term impact of new
tehnology on future humans, requires extreme detail concern. In our
house we have replaced a dozen incandecent bulbs with folded
florescent tubes which use about 1/4 as much electricity, and produce
about 1/4 as much low grade heat, which is a big plus in Florida where
we air condition about 3000 hours per year. The folded tubes are 5
times as costly at retail, but this will be payback, I think, by the
end of the 2nd summer. I suspect the folded floresent tube require 4
times as much energy to manufacture and distribute than equivelent
incandecet bulbs, but this also seems to be payback in about two
summers. The manufacture of the incandescet bulbs may release only
1/10 th as much toxic material into the inviornment as the folded
floresents, so this is a bad bargan for future humans even though the
life expectacy of the incandesent bulbs is only about 1/5 as long.  
Subject: Re: embodied energy in lighting equipment
From: kevan_shaw-ga on 29 Oct 2002 11:32 PST

Thanks for the flattery! The purpose of this exercise is to try and
become an expert on the subject before I make a fool of myself  at a
lecture next week! I note that you "suspect" the folded fluorescent
takes 4 timeas as much energy to manufacture. I am interested in what
you base this suspicion on as that is the info I have been looking for
for a number of years without substantial results.

In your situation the energy use of the incandescent light bulb is a
real liability as you are using even more energy to dispose of it. In
the Northern hemisphere where the number of heating days far exceed
cooling days I think the argument is a lot less substantial that
compact fluorescent is a good idea from any point of view! My paper
also takes issue with the replacement of functioning wire wound
ballast control gear fluorescent fittings with electronic high
frequency fittings where at best energy saving is 10-15%. In the USA
this retrofitting is also responsible for dumping a load of PCPs into
the environment as these were used in capacitors for fluorescent gear
to a much greater extent than in Europe.
The next issue I have to write up is the delusion that LEDs are a "low
energy lightsource" as is being proclaimed by manufacturers and more
gullible environmentalists, when in fact, they are rarely better than
half the efficiency of  incandescent lamps!


Kevan Shaw
Subject: Re: embodied energy in lighting equipment
From: hedgie-ga on 03 Nov 2002 23:19 PST
Hello again, Kavin and neilzero

    I would like to add few closing remarks to the interesting
posted by Kavin.  I did some more searching for the manufacturing data
proceses and found few references to manufacturing cost, which are

 Conclusion to which I came is as follow:  The simple 'accounting' -
is "CFL save 70-80% of energy" is inadequate. It may be used at most
as an
incentive to review the incadescent lighting systems. 
 To make a good decission, one has to review full cost of a retrofit
of an alternate design. Full cost includes disposal (current and
future) , which
in the case of CFL may include hazzardous materials (Hg and PCB),
 transport, packaging, heatin/cooling of the room,... 

It is clear that in many cases the retrofit, a switch to CFL will be
 by such analysis. 

So, it is really not a case of 'for' or 'against' CFL - it is case for
careful analysis of a often complex decision.

 I do not read Kavin's statement as saying 'stay with what you have'
but rather
as saying: Do full cost analysis, before investing into a costly
I also think that the 'imbodied energy' term is useful for materials,
and can be
applicable e.g. when choosing between 'aluminium vs steel' fixtures.
It is
not easy applicable to manufactured products. With proper accounting
for the
extended costs mentioned before, the economic analysis will be an
measure of ecological ipact. (Indeed, Al fixtures (with higher energy
are more expensive then similar steel fixtures).

Here is summary of (partial) cost of owning and operatiing residential
lighting systems:

Here are few, scattered and sometime complex pages on manufacturing of
fixtures and bulbs:,+light+fixture+&hl=en&ie=UTF-8

Here is an attempt to collect statistical data on cost:

Overview of US government program:
... or poorly maintained systems can cost consumers money ... and Safe
Torchiere Lighting Fixture (1997) DOE ... and transferred to the
fixture manufacturing industry and

. by being the most reliable and cost effective fixture assembly
manufacturer for today's lighting industry. We will offer
manufacturing and cost efficiency by ...

Snapshots of manufacturing process:

5 Fluorescent Lighting Outshines HIDs

Fixtures from recycled glass?

Residential lighting accounts for approximately 15% of residential
electricity use and close to $11 billion per year in consumer
electricity bills...... Fixture Market Segmentation The fixture
manufacturing market is CEE Residential Lighting Initiative 8 5 ... -

And finaly, a list of manufacturers:
Subject: Re: embodied energy in lighting equipment
From: neilzero-ga on 05 Nov 2002 18:54 PST
I don't think I can justify my ten times enviornmental impact for the
manufacture of florecent lighting except to say that incandecent bulbs
are made of glass, a few miligrams of tungstan, perhaps a half gram of
alloy wire which has the same thermal expanion as the glass, and the
metal for the screw base (2grams?) the floresent tube has about the
same ammout of material of the same materials, except plastic is often
substituted for the 2 (or more) grams of metal (2 end caps instead of
a screw base. Typically the florecent tube has more glass. So far
these materials are thought to be benighn, mostly stuff that occurs in
nature or has been made for thousands of years except the tungstan
about 2 centuries. The electrodes inside the instant start floresent
tubes may be tungstan, or some more hazardous alloy coated with rare
earth oxides. The mining and smeltering of the rare earth oxides is
significantly hasardous to our inviornment. The florecent tube may
contain a radioactive substance to help insure instant start. If so
they will avoid admitting this even if the radioactive substance is
low hazard. They have reduced the ammount of mercury in floresent
tubes, but I think it remains a significant hazzard for centuries
after the tube is taken out of service. Extracting the mercury at
mines and smelters is also hazardous long after the mine and smelter
is closed. Opinions vary. In worst case the mercury makes the
florescent tube 100 times more hazzardous than the incandecent bulb.
Except for California, the spent florescent tubes go into the land
fills by the millions, every month in the USA.  Neil
Subject: Re: embodied energy in lighting equipment
From: neilzero-ga on 14 Nov 2002 09:46 PST
Adding improperly disposed of PCBs to mercury in trashed florescent
tubes (I am still puzzled why you call them CFL) is subjective at best
and adding carbon dioxide is erroneous if we have new ice age instead
of global warming. Determining how much energy is used to make, use,
and dispose of a florescent tube is also subjective, depending on
details at the mine site for each raw material, including perhaps the
paper used by stock brokers, buyers, and sellers of the mines stock
and other financing. I really think guestimates are possible,
predujudice is a problem, but accuracy is well beyond grasp.   Neil
Subject: Re: embodied energy in lighting equipment
From: kevan_shaw-ga on 14 Nov 2002 12:21 PST

Thanks for your comments. I gave the paper last week and started a
whiole bunch of engineers and architects thinking about the subject of
embodied energy which was the aim of the piece. You are right that an
exact measure of embodied energy is next to impossible to calculate,
one thing however is critical. In order to account for variations in
the local markets throughout the world you must value the different
factors in the embodied energy at the equivalent values  at the point
of use particularly when considering the embodied energy versus the
energy in use. As is clear rom Global Market conditions energy costs
vary dramatically as does environmental impact of each kilowatt of

 In less developed countries energy is generated with little regard
for polution created. In Northern Europe and some of the USA
increasing amounts of energy are produced by non CO2 generating
processes, in the UK 25% is nuclear and about 7.5% is wind farm and
hydro electric, in France 33% is nuclear, in China 90% is coal
burning. It is essential to value the embodied energy in a relative
way, I do not know if anyone is really looking at this right now.

BTW CFL is shorthand for compact fluorescent lamps, the folded tube
type you mentioned in your earlier posting.

As a conclusion to this my paper came to the concusion that the
embodied energy in a typical 600 X 600 lay in fixture replacement ,
that is the one you throw and the one you buy requires 11 years and 9
months operation to recover with the energy saved by the increased
efficiency of the electronic ballast!

The message is Re-Use and Re-Cycle and don't dispose of anything until
it really is beyond repair.

Kevan Shaw

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