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In the There's No Tomorrow video, they affirm several things about solar panels (and a lot of other things).

The one I'm the most curious about is this:

All the world's photovoltaic solar panels generate as much electricity as two coal power plants. The equivalent of between 1 and 4 tons of coal are used in the manufacture of a single solar panel. […]

The main question I'm interested about is the second sentence: Does it really require 1 to 4 tons of coal to create only one solar panel?

That's so much that it seems crazy to me, but I might be wrong. A few Google's searches didn't yield any interesting/satisfying answers.

They do give some sources in the script, but not about the main question I'm interested about.

In the other hand, they do give a source for the first statement (that is: Paul Roberts, "The End of Oil: On the Edge of a Perilous New World" (2004) p. 191) but I don't know what it is worth.

Sources:

Part of the script concerned is here: http://www.incubatepictures.com/notomorrow/script_2_energy.shtml

You can see the part of the video I'm mentioning here: https://www.youtube.com/watch?v=VOMWzjrRiBg#t=880

jeromej
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    NB there is a difference between "**the equivalent of** between 1 and 4 tons of coal" and "1 to 4 tons of coal": solar panels don't need **any** coal *per se*. – 410 gone Apr 18 '15 at 15:03
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    Without specifying the size or capacity of the solar panels, it is a meaning less statement. However much or little energy it takes per panel area, there will always be a size that would take a given amount of energy (such as 1 ton of coal equivalent). – DavePhD Apr 18 '15 at 16:05
  • After multiple attempts by more than one mod to get the authors of the answers to fix them, we've removed the answers as "original research" until they are corrected. Please avoid back of the napkin calculations because: http://www.jameskennedy.ie/wp-content/uploads/2014/04/then-a-miracle-happens.gif – Sklivvz Apr 18 '15 at 19:46
  • @EnergyNumbers Thanks for insisting on this point. I could/should have been more rigorous about this concern. – jeromej Apr 19 '15 at 01:33
  • @DavePhD Common sense would tell me it would be a "standard" size one if not specified. The point here was, the number feeling so huge, that your "solution" could have been answered by a really giant solar panel, in which case the information would have been much fallacious in the way presented in the video. – jeromej Apr 19 '15 at 01:35
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    @Sklivvz Even if OP was (wrongly?) satisfied with the answer (I accepted it)? Ok… seems weird to me. Also, even if you guys disagree about it, I'm sad I can't see it anymore somewhere: Whichever its actual accuracy was, it was a start at least, definitely something I would want to still be able to read now. Even if there was a lot of extrapolations, it is much more documented than in the video. Also, but that might be only my personal opinion but, "multiple attempts" = only one day? Seems short to me, some people can't afford such short delays to SE. Can I still see the answer anywhere? Thx. – jeromej Apr 19 '15 at 01:41
  • The answer had objective problems, it was lacking references in a critical part and this lead to an unwarranted conclusion. You can read about them in [chat]. After addressing them, the OP got to a similar answer as the one currently visible by Larry. We are waiting for him to update the text to undelete it. As it is practice pretty much anywhere on the network, you can't expect to read off-topic content for any length of time. Unreferenced material *is*, unfortunately, off-topic on skeptics. – Sklivvz Apr 19 '15 at 09:56
  • For those interested, there is the cached version of the deleted answer http://myedit.io/v.php?is=1904b8778691 . @Skliwz let me know if I am allowed to link to a deleted answer or not. IMHO I see why this deletion system is established but I also see a flaw in that very system… Thanks anyway. Have a good day. – jeromej Apr 19 '15 at 13:06
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    How much coal-equivalent goes into building a common coal-fired electric power plant, by the way? – jjack Sep 07 '15 at 20:43
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    I know you're asking about the second claim (the amount of energy needed to make a panel) but I have some serious doubts about the first one too (the one about every solar panel in the world producing the equivalent of 2 coal power stations worth of power) – GordonM Sep 14 '15 at 11:04
  • Larry OBrien's superb 2012 reference [**The energy balance of the PV industry**](https://gcep.stanford.edu/pdfs/symposium2012/MikDale_Symp2012_web.pdf) provides an excellent overview of what you want. They say in summary that new panels exceeded energy use in manufacture in 2015 and that output of all panels ever produced will exceed energy used in manufacture by 2018. – Russell McMahon May 29 '16 at 08:22

2 Answers2

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No. A typical home panel might consume the electricity released from about 1/2 a ton of coal. (Update: Or 1/6 a ton of coal, if you use combustion energy rather than electrical generation.)

According to The Energy Balance of the Photovoltaic (PV) Industry: Is the PV industry a net electricity producer?, the Cumulative Energy Demand for photovoltaic cells ranges from around 1 kWh per watt of PV capacity to around 6 kWh/W (although there are outliers that drive those costs up to as much as 15kWh/W).

According to Solar Panel Output: What’s the Average?:

The average solar panel output ranges from about 175 W to about 235 W, with an exceptionally powerful solar panel measuring 315 W. Among the top ten manufacturers, the average wattage of a panel is about 200 W.

Multiplying 200W per panel by the high-but-not-outlier cost of 6kWh/W suggests that it might require around 1200kWh to produce.

According to Energy Information Sheets a ton of coal produces around 2000kWh of electricity.

Update: Per @DavePhd's comment, a more common way to measure the "energy in a ton of coal" is to use the combustion energy of 8141kWh / ton. This makes the statement closer to "A typical home panel might consume the energy released from about 1/6 a ton of coal."

The previously referenced "The Energy Balance of the Photovoltaic (PV) Industry: Is the PV industry a net electricity producer?" article addresses what seems to be the root question, which is whether, and when, PV panels become net-energy positive. The author's conclusions:

  • The PV industry almost certainly became a net power provider by 2015.
  • The industry will ‘pay back’ the electricity consumed in its early growth by 2018.
Larry OBrien
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    And of course, if you require only the energy equivalent of the 1/2 ton of coal, and not the coal itself, you can manufacture it from a clean(er) energy source... – Clockwork-Muse Apr 20 '15 at 09:13
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    @Clockwork-Muse Perhaps even from existing solar panels? –  Jul 23 '15 at 19:12
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    The question is regarding the manufacture of Solar Panels, not the energy output of them. – VolleyJosh Sep 08 '15 at 19:08
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    @VolleyJosh the figures in the answer are given per-watt , how much energy used to manufacture a single W of PV power. – Jeff Lambert Nov 13 '15 at 15:00
  • @LarryOBrien coal equivalent usually has a different meaning than the one you've used. You are using energy of the electricity produced from a ton, while combustion energy per ton is more standard. 8141 kWh per metric ton accord to https://www.euronuclear.org/info/encyclopedia/coalequivalent.htm and http://www.convertunits.com/from/kWh/to/tonne+of+coal+equivalent Overall, good answer, +1 – DavePhD May 27 '16 at 12:08
  • @DavePhd So would it be (~1200kWH / 8141 kWH) ~= 15% ? "The typical home panel might consume the energy of about 1/6 a ton of coal"? – Larry OBrien May 27 '16 at 23:05
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    @LarryOBrien Yes. A reference that is more specific about this is http://www.solaik.ch/_downloads/EnergyPaybackTime.pdf where it gives the "primary" energy required in MJ per kW of solar panel capacity at peak power, for various types of photovoltaics. – DavePhD May 29 '16 at 23:15
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Larry already answered the question about the manufacture cost of a single solar cell, so I'll answer the other question.

All the world's photovoltaic solar panels generate as much electricity as two coal power plants.

False.

Here is a link from the Union of Concerned Scientists stating that the average (admittedly US) coal fired plant generates, on average, 547 MW.

Here is a report from the International Energy Agency reporting that the total worldwide solar capacity to be approximately 230 GW.

This puts the total world PV capacity as equivalent to 420 American Coal power plants. To put that in perspective, as of 2012, there were 572 Coal Plants active in the United States.

DenisS
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    "Generates" and "Capacity" are [two totally different things](https://en.wikipedia.org/wiki/Capacity_factor#Real_world_capacity_factors), so expressing PV capacity relative to coal generation is incorrect. – Ken Y-N Jun 01 '16 at 01:10
  • @KenY-N, photovoltaic's capacity factor isn't too spectacular (I'm seeing numbers around 10%-20%), but that's nowhere near the 0.5% needed to make the statement true. – Mark Jun 01 '16 at 01:34
  • This part of the claim is definitely false now, but the source in the OP is from 2004. Maybe the claim was true at that time. – DavePhD Jun 01 '16 at 03:14
  • I didn't say the overall statement was true - I was challenging "total world PV capacity as equivalent to 420 American Coal power plants" only. – Ken Y-N Jun 01 '16 at 03:26