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Crashley

(101)

I find this discussion very interesting. To my knowledge, NO ONE in the media mentions that it takes lots of energy to produce solar panels, or even attempts to say how long they must produce energy to break even.

I think it still makes sense to manufacture, use, and improve them as eventually the energy to produce them could come from PV and other renewable sources. I was surprised to see how long this discussion has been going on. Good work.

PS: I've been in the satellite business for almost 35 years and PV and batteries are the only way to go for a 15+ year lifetime. Talk about off the grid.

Crashley

(102)

A 12kW triple junction GaAs solar array in space produces about 1.5 GWh in 15 years. How many Wh do you think it took to produce it? (I don't know) Obviously it does not offset any terrestrial energy production since there is no other way to get power to the satellite

I realize this is not really relevant to the discussion, but I am curious.

By the way, the "scorecard" site did not seem to address how many Wh it takes to produce a W of solar panel output. Or maybe I missed it.

Jamey Johnston

(103)

Seem like there is a scholarly / engineering disagreement, hmm?

https://energy.stanford.edu/news/PV-industry-likely-net-energy-producer

pam

(104)

know-it-all rants by Devry tech grads like dana are really impressive...

Slowburn

(105)

Photo-voltaic is the wrong way to harvest solar energy. Use solar water heaters to drive absorption heat pumps, and Stirling cycle engines. Expand the ammonia through modified water cool ICE so that as well as generating the mechanical energy you get to keep the cool for food preservation, air-conditioning, & and water harvesting. This also give inherent energy storage as you do not release the anhydrous Ammonia to the engine until you need the power whether to directly drive a machinery or generate electricity.
Don't forget to harvest the waste heat from the heat pump's condenser.

Wouter Carrette

(106)

Did anyone even figure in the transportation CO2 footprint?
As most panels are produced in China, they still need to be moved to the rooftops in Europe/the US. How about that?

Peter

(107)

I think producing and using solar power systems, the positives far outweigh the negatives. Sure it will cost some to produce, but with the climate in such a fragile state as it is, ignoring the issue is not the answer. There seems to be so many misconceptions about solar, and you have to wonder where the rumours of this energy system get started, and whom it benefits in the long run? My bet is that for those who are invested in other energy systems would love to spread these negative issues around. Here is a helpful little article that I co-wrote about with an electrical contractor, that discuss the 7 top questions, and we were hoping to dispel the misconceptions in a casual way around solar power -
https://east-westelectric.com/the-top-7-questions-when-it-comes-to-solar-panels/

Abacus

(108)

Ok so we need to consider the amount of CO2 emission in total to produce 1 square meter of Solar Panel from scratch. Take that number to calculate the total CO2 cost over the life span of 20-30 years. Then compare that with the total amount of CO2 produced by Coal/Gas in the period of 20-30 years. WHERE do you account for the amount of CO2 cost to produce the entire infrastructure to support the entire Coal/Gas Industry ? It does not take a math genius to figure out what is wrong

ZMacZ

(109)

Hold ur horses.

It's comparing to regular fossil fuel production.

There's a few parts missing:

-carbon footprint into producing the materials to use fossil
fuels, like boats to move the oil, refineries, gas stations,
moving of oil products to gas stations etc. THAT has a big
fat carbon footprint as well.

-the lifespan of solar panel isn't 20 years or even 25,
the lifespan is until it stop producing electricity
altogether, which in my modest opinion is well in the 100
years range, until the last cell drops out.

For a typical solar panel 260 Wp, that would be (@6 solar
hours per diem) 6x365x100x260x50% (WP x average efficiency over 100 years) roughly 28.5 MWh, until the last cell dies and gives up it's yield. (this is very conservative, since the more modern solar panels do even less than 1% reduction each year, making their lifespan even greater than 100 years).

And then, ofc, using solar power (nothing but), to produce
solar power, which will be the way to the future.

In all, the 'conclusion' of such a report leave salot to be
desired, and should also be done by actual scientists, not
'hired' 'scientists' who have used half a brain to come up
with some calculation, that does NOT reflect ALL variables
involved, and also assumes that the solar panels will simply
'die' after a mere 20 or 25 years.

So, nope, MY conclusion is still, solar panels are well
worth the effort, and over time will power the world,
in it's entirety.

I also foresee the synthesis of fossil fuels,
by means of high atmosphere CO2 harvesting,
but that's another story.

ZMacZ

(110)

One more thing, when solar panels reach EOL, they can be harvested for the same materials that is required for the production of new cells. And that certainly generates a brand new re-use factor.

The breakdown of most solar cells is due to local high energy in the cells themselves, both from UV and electrons, causing electron migration. However, electron migration does not cause any chemical change, and only breaks down connections within the cells themselves.
Knowing that there's only 2 substances in the degraded solar cells, they only need separating and 'reformatting' back into whole cells.

Ofc, there's a price to it, and yet this is much lower than
production from raw materials. So, no, solar panels still better.

Ian

(111)

https://www.forbes.com/sites/michaelshellenberger/2018/05/23/if-solar-panels-are-so-clean-why-do-they-produce-so-much-toxic-waste/
Old but still current nh3
70 million tons on the docks waiting to be taken away

Burt Sidefish

(112)

hey Kriss, if you are still reading these comments
as I understand it, a big source of the emissions for silicon cells is in refining the silicon from silica, which oversimplified looks like this: SiO + C -> Si + CO2
which can't be shunted with solar power, although the process is also energy intensive...which is why onsite solar probably isn't common, needs a big and steady power supply that a solar based grid can supply but onsite cannot.

I have a dream of hydrogen refined silicon using a solar concentrator but I don't know how I could achieve it, I being just some internet armchair warrior.
I hope we find a way to continue living.

Greg

(113)

OK, so somebody worked out the carbon footprint of producing the solar panels that generate electricity, and it's still somewhere between marginally & much better than burning coal.

Now lets compare like-for-like: What's the carbon footprint of constructing a coal power plant? (hint: there's a lot of concrete in there). What's the carbon footprint of building & running a coal mine? and trucking the coal to the power plant? PV solar still wins by a big margin.

Now lets get to the much more important question: Why are we still debating this?

Antonio Lambe

(114)

Thank you for a VERY topical article with many well-informed comments (and some quite misinformed and even boorish ones).
But the piece is >10-years-old and, as the author anticipated, the technology has since improved. Might an updated version be possible?

kris de decker

(115)

@ Antonio

There is an updated version from 2015: https://www.lowtechmagazine.com/2015/04/how-sustainable-is-pv-solar-power.html

Martha Kennedy

(116)

Well it's now 2020 and we just moved to Colorado. And solar is BIG BIG here. I'd just like to ask what are all these people going to do when the gas and oil run out??? Cause make no mistake it will. But hey guess that'll be our kids problems huh? Along with land that has been gashed open to ha e it's minerals ripped out causing deforestation, flash flood risks.Then toi can go into all the health conditions miners are prone too. As for my household we will be checking into solar soon

Kin Rocker

(117)

This is completely stupid.

"Next, they divide the amount of CO2 emitted for the production of one square meter of solar panels by this lifetime electricity generation – and that’s how they achieve their conclusions."

In other words, the authors calculate a CO2 footprint of solar panels based on the assumption that we don't use renewables for generation. Let me turn that around and assume we use only renewables, in which case the CO2 footprint becomes zero. Not the same can be said about fossil fuels.

Let's call out this lack of logic, please.

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