Retrograde <
fungus@amongus.com> writes:
On 25 Jun 2022 17:13:20 -0300
Mike Spencer <mds@bogus.nodomain.nowhere> wrote:
Final results of a <LINK three-part Energy Department-funded study>
reveal the most comprehensive comparison to date.
Trying http://www1.eere.energy.gov/buildings/ssl/tech_reports.html
Sorry I didn't see this sooner. See if the following are any help.
https://www1.eere.energy.gov/buildings/publications/pdfs/ssl/2012_LED_Lifecycle_Report.pdf
Thanks for the pointer.
Trying that one first. (We all trust the .gov don't we? :-)
After a quick look far more cursory that it deserves, I see:
2.1.2 Life-Cycle Impact Assessment
Although a life-cycle impact assessment (LCIA) is not conducted
for this analysis....
[snip]
In general, an LCIA will consider impact categories including
global warming potential (GWP), natural resource depletion, ozone
depletion, eutrophication, acidification, human toxicity, and
aquatic toxicity. These categories aim to simplify the complexity
of potentially hundreds of flows into a few environmental areas of
interest....
They give a lot of attention to energy consumed (in
megajoules/20M-lumen-hours) over the lifetime of incandescents and
LEDs -- including manufacture, transport and use. Looking only at
energy consumption, the amount used in mfgr and transport appears tiny
compared to the amount consumed in lifetime use. The graphic used to illustrate that comparison whacks your eye with how much better LEDs
are. It is exactly the kind of graphic that Edward Tufte wrote two
books about why not to use them and how to notice them when someone
else does. The difference between the non-use energy costs appears
very large but is visually minimized by the large use-energy
difference. The former seems not to be documented numerically and
end-of-life (disposal/recycling) is mostly mentioned in passing:
...currently no standardized recycling procedures exist for LED
lamp products (Hendrickson, 2010).
See "LCIA", supra.
It still strikes me that something is wrong if an incandescent
contains one tungsten filament while the LED contains 4 capacitors, 7 microchips, a transformer and a soldered cuircuit board in an aluminum
(lots of enegy to mfgr.) and plastic (petrochemicals) shell.
From another source, Wikipedia says:
Incandescent bulbs typically have short lifetimes compared with
other types of lighting; around 1,000 hours for home light bulbs
versus typically...20,000-30,000 hours for lighting LEDs.
I've found that to be an enormous exageration for (household
lightbulb) LED lifetime. I still have a stash of incandescents but
have been buying halogen and LED domestic bulbs. Both LED and halogen
keep failing while the incandescents keep chugging along.
https://www.led-professional.com/resources-1/articles/on-life-cycle-assessment-to-quantify-the-environmental-impact-of-lighting-products
Haven't looked at this one yet. Can I expect "LED-Professionals" to
be honest about LEDs? :-\
--
Mike Spencer Nova Scotia, Canada
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