Talk:Solar cell

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Former good articleSolar cell was one of the Engineering and technology good articles, but it has been removed from the list. There are suggestions below for improving the article to meet the good article criteria. Once these issues have been addressed, the article can be renominated. Editors may also seek a reassessment of the decision if they believe there was a mistake.
Article milestones
January 6, 2006Good article nomineeListed
March 12, 2006Good article reassessmentDelisted
Current status: Delisted good article

Citations needed[edit]

it must be noted that large tracts of this article are entirely uncited. This is particularly true in the highly mathematical and physics-based sections, as well as some of the more commercial and recent-ist claims. Surely, so much of this article was not written merely from memory or guesswork? This could by a symptom of serious problems in the article and needs addressing.

Apart from the lead, which may be considered an exception, particularly uncited sections are:

  1. Solar cell#Applications and implementations
  2. Solar cell#Simple explanation
  3. Solar cell#Photogeneration of charge carriers
  4. Solar cell#Charge carrier separation
  5. Solar cell#The p-n junction
  6. Solar cell#Connection to an external load
  7. Solar cell#Characteristic equation
  8. Solar cell#Open-circuit voltage and short-circuit current
  9. Solar cell#Cell temperature
  10. Solar cell#Series resistance
  11. Solar cell#Shunt resistance
  12. Solar cell#Reverse saturation current
  13. Solar cell#Ideality factor
  14. Solar cell#Quantum efficiency
  15. Solar cell#Maximum-power point
  16. Solar cell#Comparison of energy conversion efficiencies
  17. Solar cell#Light-absorbing materials
  18. Solar cell#Bulk
  19. Solar cell#Crystalline silicon
  20. Solar cell#Thin films
  21. Solar cell#Light-absorbing dyes (DSSC)
  22. Solar cell#Nanocrystalline solar cells
  23. Solar cell#Silicon solar cell device manufacture
  24. Solar cell#Lifespan
  25. Solar cell#Low-cost solar cell
  26. Solar cell#Current research on materials and devices
  27. Solar cell#Metamorphic multijunction solar cell
  28. Solar cell#Polymer processing
  29. Solar cell#Transparent conductors
  30. Solar cell#Infrared solar cells
  31. Solar cell#Validation, certification and manufacturers
  32. Solar cell#United States

That is a huge list of largely uncited sections for one article! --Nigelj (talk) 17:30, 11 September 2010 (UTC)

Here is a suggestion for a "Tandem Solar Cells" citation. This needs to be reviewed before inclusion IMO. (talk) 06:24, 7 March 2017 (UTC)

Along the same lines, the Lifespan section previous cited, which did not support any of the claims made in the Lifespan section. As a result, I removed the irrelevant citation, and added "Citation needed". -- 1 November 2011 — Preceding unsigned comment added by (talk) 21:52, 1 November 2011 (UTC)

Geography and sunlight[edit]

I think it would be useful if the article introduced the reader to the concept of the relationships between the amount of sunlight incident upon a solar cell and geographic location (latitude, amount of sunlight available, time of year, etc). This aspect seems relevant insofar as one might try to access this article in an attempt to evaluate the feasibility of a system utilizing solar cells (panels/modules/arrays etc). It is not necessary to cover this aspect entirely - the article might point the reader to other resources that might adequately answer these questions. (talk) 19:41, 21 October 2010 (UTC)

The relation of sunlight and geography is covered in Solar radiation and Insolation. Jojalozzo 00:44, 22 October 2010 (UTC)

Warranty example[edit]

To source information about panel warranties we have used an actual example but some of us have been concerned about accessing this as an external link to a commercial web site. Does anyone have any ideas about how to source warranty information without sending readers to a commercial site? Jojalozzo 18:55, 11 November 2010 (UTC)

Answered my own question (, but if anyone can improve on that, please do. Jojalozzo 19:01, 11 November 2010 (UTC)

Link to place in article[edit]

I am not sure, that this link may be placed directly to main article. An article about producing solar cells for Russian space ships. Sergei Frolov (talk) 10:31, 12 November 2010 (UTC)


The "Cost" section in the article about solar-cells contains an interesting discussion, but no real information about cost. The section should contain information about actual cost, in dollars, of solar cells currently available for purchase.

The article states that cost for solar cells is given per unit of peak electrical power, but it seems to me that cost per square meter would be a much more useful parameter. DougGeo (talk) 21:32, 12 February 2011 (UTC)

Cost per unit of peak output is the standard way of talking about cost in the PV industry. The reason for this is that ultimately, buyers of solar cells are interested in how much energy they will get for their dollar, not the number of cells or the number of square meters, and in this context, peak power is a reasonably good and easy-to-understand proxy for energy (there is a debate about whether this can be improved, but that is for another discussion). As a result, low-efficiency solar cells tend to cost much less to manufacture and sell (per cell and per square meter) than high-efficiency ones, but they are roughly equal on a cost-per-peak-watt basis. Therefore, the cost per-cell or per-square-meter is strongly dependent upon cell efficiency, while the cost per peak watt is independent (or, more accurately, only weakly dependent) upon cell efficiency.--Squirmymcphee (talk) 16:35, 19 February 2011 (UTC)

Three generations[edit]

Thin films, the second generation, had 40% market share in 1988 and it has steadily declined since then, there was a brief resurgence with CdTe which ended last year when the market share of thin film again dropped by thirty percent to less than 13%. More than eighty seven percent of commercial solar cells are made with crystalline silicon and thin film is very much yesterday's technology. (For the data see March issues of Photon International for each of the last ten years) The three generation discussion is misleading and is a technology judgement that is neither objective nor accurate.

Organic solar cells could be the third generation, well maybe. Plants have an efficiency of 1% this is an order of magintude lower than today's solar cells. There will be other solutions to better solar cells. Maybe someone might invent an inexpensive tandem cell. A photo converter that converts a blue photon into two red photons that are well matched with the PV bandgap might become the next best technology. Who knows, I don't and the three generation people don't know either it is premature to crown either a second or a third generation.

I deleted the text three generation text with the intend to make wikipedia better.

Cleanenergy (talk) 21:58, 11 June 2011 (UTC)

I agree 100% with deleting it. "Three generations" is sometimes used for one person's opinion of the future of solar cells, and other times used as a vacuous marketing slogan. :-) --Steve (talk) 22:05, 11 June 2011 (UTC)

Merge from Fill factor to Solar cell#Efficiency[edit]

The Fill factor article has a concise discussion of the term (and a citation) as used in photovoltaics and then mentions a couple of other uses of the term in other areas. My proposal is to merge the PV portion into Solar cell#Efficiency and leave the existing article as a disambiguation page for the general term. Jojalozzo 14:56, 19 June 2011 (UTC)

I agree: Fill factor, in this context, is only about efficiency, which can be handled in a small paragraph here.Peter Chastain (talk) 17:39, 3 August 2011 (UTC)
Done. We didn't need nearly as much math as it had, and defining terms in English instead of math subscripts is probably a good plan everywhere in an encyclopedia. --Wtshymanski (talk) 18:21, 4 September 2011 (UTC)

Environmental aspects[edit]

Well, I must say that it occurs very rarely that "our" German Wikipedia articles are light years better than their English equivalents. However, this time it is the truth: de:Solarzelle#Umweltschutz. What, in contrary to that, has this English article been turning to over the years from its creation back in 2006? To me it's a PR pamphlet written by solar cell enthusiasts. Or why are the environmental aspects mentioned nowhere? The toxicity of cadmium; the highly problematic residues from SC production; the greenhouse effect provoked by the gases used in the lavation phase; and ... and ... Everything reads as if solar cells are the most eco-friendly thing ever. Well, once in use, YES; but while they're produced, residue accumulates that has to be treated in a special way. Some of them might (assuming!) even produce toxic waste, i. e. relics with long-lasting effects. -andy (talk) 11:52, 3 August 2011 (UTC)

I agree this article could use some discussion of the environmental aspects of PV production, since it is meant to be an eco-friendly technology. However, if my rudimentary German and Google Translate have come anywhere close to a correct translation of the section you link to, the German Wikipedia entry is hardly a paragon of quality. As far as I can tell, it is mainly a FUD piece that attempts to demonize solar cells on the basis of CdTe solar cell processing. These cells make up about 5% of global production and, while I'm no great defender of CdTe, they contain no cadmium metal (as the supposedly high quality German article states without reference). Before you object, let me put that another way: Saying that CdTe solar panels contain cadmium metal is exactly like saying water contains hydrogen gas. There are certainly occupational safety issues -- cadmium metal is involved in the production -- and there may also be toxicity issues in the field, but so far testing has not been able to prove the latter.
Anyway, this is supposed to be a place for discussion of the article, not so much the article's contents, so I will stop there. You're welcome to add something on the environmental aspects of course, but if you plan to translate the German version I strongly suggest you gather a few more references. (I'm not likely to do it myself, at least not anytime soon.)--Squirmymcphee (talk) 17:15, 8 August 2011 (UTC)
I'm less concerned about cadmium than about NF3.
Especially in (resp. above) China alarming levels of NF3 have been measured already. And it will stay up there quite a while. For more info on this highly potential greenhouse gas see - sonny22 — Preceding unsigned comment added by (talk) 11:56, 20 July 2017 (UTC)

Solar thermal resource in BusinessWeek[edit]

Solar Panels Start to Outshine Mirrors; As prices for photovoltaic cells tumble, developers are abandoning solar thermal plants October 13, 2011, 5:00 PM EDT by Ben Sills (talk) 23:38, 18 October 2011 (UTC)

Crap state of the article[edit]

Andy is right. current article This article is an internal memo for some firm on a planet far far away. Go nuts on the hack and slash, if anyone wants or needs a third, I'll be happy to help. You could machine-gun this article with templates there are so many sections that are rubbish in so many ways. Someone needs to learn how to plagiarize their own companies brochures for an encyclopedic audience. Penyulap talk 16:16, 24 October 2011 (UTC)

If not crappy, then unintelligible in places[edit]

"Other technologies have tried to enter the market. First Solar was briefly the largest panel manufacturer in 2009, in terms of yearly power produced, using a thin-film cell sandwiched between two layers of glass. " Why is this a different technology..... even if the content in the article is ok (and it does need some work--took me a while to figure out where the history of development material was ) it reads as if it hasn't been proofread by the last person who edited it...commas and verb tenses count...the preview feature is there for a reason...please read your edit after you post it to make sure you are not obfuscating a clear point or concatenating stupidly. Eliminate run on sentences....etc etc , etc... Avram Primack (talk) 15:57, 9 November 2011 (UTC)

To consider for inclusion[edit]

  • lay summary "Addition of quantum dots to solar cells gets dramatic results", R&D Magazine, Advantage Business Media,, 23 Jan 2012, retrieved 23 Jan 2012
  • peer-reviewed publication Sablon, Kimberly A.; Little, John W.; Mitin, Vladimir; Sergeev, Andrei; Vagidov, Nizami; Reinhardt, Kitt (5 May 2011), "Strong Enhancement of Solar Cell Efficiency Due to Quantum Dots with Built-In Charge", Nano Letters, 11 (6): 2311–2317, doi:10.1021/nl200543v, retrieved 23 Jan 2012 More than one of |at= and |pages= specified (help)

—User:Ceyockey (talk to me) 01:55, 24 January 2012 (UTC)

This page disagrees with another wiki.[edit]

Please note that the efficiency section states that "Single p-n junction crystalline silicon devices" are nearing 37.7% efficiency as is in-line with the Shockley Queisser limit but the Shockley Queisser limit page (linked below) states a maximum of 33.7% (which is the only reference of the claim).

Either one of the numbers on one of the pages are wrong or the Shockley Queisser limit is incorrect, which I strongly doubt. The link in the Shockley Quesser page directs the user to the below linked source which says 30%. Since I don't know which number is right, I'll leave it to others to make the appropriate correction. — Preceding unsigned comment added by (talk) 15:15, 3 February 2012 (UTC)

Confusing image caption – "Mono" and "Multi"[edit]

File:PV Technology.png
Market share of the different PV technologies In 2010 the market share of thin film declined by 30% as thin film technology was displaced by more efficient crystalline silicon solar panels (the light and dark blue bars).

The caption in the image in the section Solar_cell#Thin_films is confusing. What is "Mono" and "Multi"? "Monocrystalline" and "Multicrystalline"? "Mono-Junction" and "Multi-Junction"? Tony Mach (talk) 10:00, 27 April 2013 (UTC)

You're right, it is confusing. I tagged the image page itself with {{Unreferenced}} (I'm not sure if you can do that to an image page, but hey-ho). The user who created the image doesn't seem to have contributed to Wikipedia since 2011, and their talk page is mostly a reminder to cite sources. --Nigelj (talk) 13:13, 27 April 2013 (UTC)

current events section[edit]

the current events section references 2011, it's 2013 and the prices have been moving hard. It may be worthwhile to update this.--Patbahn (talk) 21:40, 27 April 2013 (UTC)

Efficiency - Shockley-Queissner[edit]

In the 'Efficiency' section, there is:

"Single p–n junction crystalline silicon devices are now approaching the theoretical limiting power efficiency of 33.7%, noted as the Shockley–Queisser limit..."

But in (the 'Shockley-Queissner limit' article) there is:

"The limit places maximum solar conversion efficiency around 33.7% assuming a single p-n junction with a band gap of 1.34 eV (using an AM 1.5 solar spectrum).[1] That is, of all the power contained in sunlight falling on an ideal solar cell (about 1000 W/m²), only 33.7% of that could ever be turned into electricity (337 W/m²). The most popular solar cell material, silicon, has a less favourable band gap of 1.1 eV, resulting in a maximum efficiency of 29%."

So it sounds to me that in this (Solar cell) article, the single p-n junction crystalline SILICON solar device would have a theoretical limit of 29%, not 33.7%. The 33.7% limit applies to some other semiconductor with a 1.34ev band gap, (NOT silicon, which is 1.1eV).

Right? (talk) 00:54, 24 October 2013 (UTC)

Not quite. Auger-recombination limit 29%. S-Q limit 33.7% — Preceding unsigned comment added by (talk) 09:05, 28 December 2013 (UTC)

Electrical Circuit Diagram Symbol ?[edit]

Please would someone add the electrical circuit diagram symbol for a solar cell? Thanks ! Darkman101 (talk) 19:58, 29 December 2013 (UTC)

Current lede is gibberish[edit]

I'm here to learn about the topic, so I am not sure how to fix it without introducing error but....if anyone is following this page, please at least try to fix the grammar. Also, how can it also be called a photovoltaic cell if it is a type of photovoltaic cell? Seem like one of those statements is partly wrong Elinruby (talk)

Photovoltaic cell a type of solar sell?[edit]

On the Dutch wiki it is said that a photovoltaic cell is a type of solar cell. Here it is stated that these are exactly the same things. I am confused on what is correct. Can someone point out some literature to put some light on this? Kind regards, Timelezz (talk) 21:12, 25 February 2014 (UTC) The Dutch wiki says:

Kind regards, Timelezz (talk) 21:16, 25 February 2014 (UTC)

Thin film[edit]

The article seems overly detailed on this topic, given that there is a separate article focused on it. I propose we move the details to Thin film solar cell. Lfstevens (talk) 03:54, 24 June 2014 (UTC)

Hi Lstevens, the entire section Solar_cell#Materials needs a thorough revision. Are you interested in some team work? Pls let me know. - Rfassbind (talk) 07:35, 19 September 2014 (UTC)

Research Cell Efficiency Chart[edit]

The latest NREL solar cell efficiency chart is now available again from WikiCommons: PVeff(rev140627).jpg. Could someone add this back to the Efficiency section of the Solar Cell article and the Solar Cell Efficiency article? — Preceding unsigned comment added by Dgwinner (talkcontribs) 18:57, 16 July 2014 (UTC)

done.Mion (talk) 19:32, 16 July 2014 (UTC)
Has somebody an idea how to tell Dgwinner (talk, that he doesn't need to upload a new file every time a revised efficiency chart is published. Instead, the "Upload a new version of this file" option should be used and the linked filename would remain the same...see here - Rfassbind (talk) 07:43, 19 September 2014 (UTC)
The file names contain a revision number on purpose, in the future you could do historic research on how efficiency changed over time. This adding was only problematic because someone deleted the chart for some reason, now its back you only need to change the version number on the image link, like before :) Mion (talk) 21:06, 19 September 2014 (UTC)
You don't seem to understand what "uploading a new version" means. The previous files won't be deleted. They are still available in the history (even better: they are listed altogether in a chronological order). Uploading a "new version" has the advantage that there is no need to amend a wikipedia article that links to the file. Currently different articles link to different files. Do a search on WikiCommons with the keyword PVeff( and see for yourself what pops up and which article links to which version.... - Rfassbind (talk) 21:26, 19 September 2014 (UTC)
I would be nice if commons had version control on images, but i think the uploader is the one that uploads the different named versions, here :[1] is no mention of version control. Mion (talk) 21:36, 19 September 2014 (UTC)
I don't know why you are being so stubborn about this. But never mind. I found the file I was talking about and amended the article accordingly. - Rfassbind (talk) 05:04, 20 September 2014 (UTC)

Upcomming revision in 2014[edit]

I will start to revise large parts of this article in the next few weeks. Pls help me with your feedback and copy-edit skills whenever you can. Intermediate steps include:

  • Revision of the articles layout and image choice
  • Revision of the "Materials" section ("Cell types and materials")
  • Cutback on the excessively large "Research section" and merge them with "Cell types and materials"
  • Adding section about how a solar cells works
  • Replacing lead section

Plz add your ideas and make constructive suggestions. Older comments on this talk page are rather disencouraging. Thx -- Rfassbind (talk) 15:29, 14 October 2014 (UTC)

Endeavour House is one of the most eco-friendly office buildings in Europe as it has 51,000 photovoltaic cells so there should be a section for this type of energy in buildings. Wrightie99 (talk) 13:24, 29 October 2014 (UTC)
Dont Cutback on the excessively large "Research section" and merge them with "Cell types and materials", The article has to keep a split between proven commercial/market ready technologies and the technologies that are still in the maturing phase (research). For the rest, good plan, always nice to see an article getting updated in time. Mion (talk) 14:33, 29 October 2014 (UTC)
Is there anyone else beside me, who disagrees with Mion about the trimming of the research section (e.g. this→Solar cell#Organic/polymer solar cells)? This section is totally out of proportion, while other important sections are completely missing (see list above). I won't go through all the hassle revising the article, if we can't even agree on the most simplest things. -- Rfassbind (talk) 17:26, 29 October 2014 (UTC)
Ah, the all or nothing approach :) well, i think we have a misunderstanding, i thought you where going to destroy the research section, but trimming a text back to 5 lines is perfect. Mion (talk) 21:23, 29 October 2014 (UTC)
Hi Wrightie99, the article you mentioned (Endeavour House), may be mentioned in Green building (also named Energy efficient buildings). Also, since the article is about a building with 50,000 photovoltaic cells incorporated into the glass curtain walls, it would be worth mentioning in the article Building-integrated photovoltaics, but not in this generic article about Solar PV cells. Do you agree? Why don't you take a look at the two articles I mentioned and see if you can do something there? Cheers, -- Rfassbind (talk) 17:26, 29 October 2014 (UTC)

Grid parity[edit]

Grid parity is now in 19 countries [2] 2014 outlook DB. Mion (talk) 19:35, 30 October 2014 (UTC)


Shouldn't this and 'solar panel' be merged? Or are they completely diffrent things? Can someone please tell me McTreevil (talk) 13:43, 19 April 2015 (UTC)

McTreevil, I'd say "no" on a merge in general as solar panel article is about modules containing one or more cells while this article is about the history and technology of the individual cells. There is some cell specific information in the solar panel article that should be here. There's also Photovoltaic system which includes all of the other stuff needed to make the panels usable. Unfortunately, the first two articles suffer from poor sourcing and insertion of POV language by manufactures, sellers, installers, and PV advocates. The photovoltaic system article is in slightly better shape. --Marc Kupper|talk 23:18, 28 April 2015 (UTC)
  • How about merging this article with photovoltaics? "Photovoltaics" is just a long word for solar cells, and the two articles seem to be about the same thing. Geoffrey.landis (talk) 22:25, 20 June 2015 (UTC)

Exxon didn't exist[edit]

The article gives I think a bit too much prominence to Elliot Berman and Exxon Solar Power Corporation, who were by no means the only player in developing low cost photovoltaics. I would like to challenge this statement (under price reductions), however: "In late 1969, Elliot Berman was investigating organic solar cells, when he joined a team at Exxon SPC who were looking for projects 30 years in the future." (SPC = Solar Power Corporation). Exxon didn't exist in 1969. This timeline [3] dates Exxon Solar Power Corporation to 1975. Geoffrey.landis (talk) 23:24, 20 June 2015 (UTC)

got it-- found a reference, and SPC was funded by ESSO, not Exxon. Geoffrey.landis (talk) 23:38, 20 June 2015 (UTC)

Cite (currently 41) URL expired[edit]

This url seems to have expired. There's no marks on it for when this was added or last accessed. "Cite book | doi = 10.1115/SED2002-1051| chapter = Net Energy Analysis for Sustainable Energy Production from Silicon Based Solar Cells| title = Solar Energy| pages = 181| year = 2002| last1 = Pearce | first1 = J. | last2 = Lau | first2 = A. | isbn = 0-7918-1689-3|url=" — Preceding unsigned comment added by (talk) 17:59, 15 August 2016 (UTC)

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Selenium Cell redirects here.[edit]

Although Selenium Cell redirects here, there's not a lot of information about it in the article. Even German Wikipedia has a dedicated article: de:Selenzelle-- (talk) 20:51, 8 March 2018 (UTC)

Selenium cells were usual for light meters in the 1950's and 1960's, until photoresistor CdS took over. I suspect that the physics isn't so well understood, which might be one reason they are not described. In some sense, all solar cells, that is photovoltaic, work pretty much the same way, as p-n junctions. That is easy to see in the case of doped crystalline silicon, but not so easy for amorphous selenium. Also, selenium cells have poor long-term reliability. (Look at old camera meters, and see how many still work.) As well as I know it, it is amorphous selenium on copper, which forms the p-n junction, and a thin gold electrode on top, that lets enough light through, but also conducts well enough. Then there needs to be some contact to the gold, which might be the cause of long-term failure. The efficiency is low, but they worked well enough for photographic light meters for many years. Gah4 (talk) 22:20, 8 March 2018 (UTC)

Hasn't been updated since 2016 in many sections[edit]

Factual numbers like cell efficiencies, prices per watt, or deployed world capacities, do not appear for any date after about 2012-2016 in various parts of the article. Some parts describe "forecasts" for 2017. Edits from someone who's conversant with 2019 efficiencies, market makeup, and prices (and can cite references for them) could really benefit this article. Gnuish (talk) 06:24, 13 February 2019 (UTC)

"Solar Cell" or "Photovoltaic"?[edit]

Sorry, is this article about "solar" cells or about photovoltaic cells/photovoltaic devices? Because they are not the same thing, and when I was last editing this article (re-writing it, really), my edits reflected this. If you don't know that they're not the same thing, or can't understand how they would be two different things, it seems likely that you should not be editing this article. — Preceding unsigned comment added by (talk) 05:16, 29 June 2019 (UTC)