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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

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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
    Commented Apr 18, 2015 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
    Commented Apr 18, 2015 at 16:05
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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
    Commented Apr 19, 2015 at 1:41
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    How much coal-equivalent goes into building a common coal-fired electric power plant, by the way?
    – jjack
    Commented Sep 7, 2015 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
    Commented Sep 14, 2015 at 11:04

2 Answers 2

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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.
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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
    Commented Apr 20, 2015 at 9:13
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    @Clockwork-Muse Perhaps even from existing solar panels?
    – user17430
    Commented Jul 23, 2015 at 19:12
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    The question is regarding the manufacture of Solar Panels, not the energy output of them.
    – VolleyJosh
    Commented Sep 8, 2015 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
    Commented Nov 13, 2015 at 15:00
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    @LarryOBrien Yes. A reference that is more specific about this is 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
    Commented May 29, 2016 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.

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    "Generates" and "Capacity" are two totally different things, so expressing PV capacity relative to coal generation is incorrect.
    – Ken Y-N
    Commented Jun 1, 2016 at 1:10
  • @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
    Commented Jun 1, 2016 at 1:34
  • 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
    Commented Jun 1, 2016 at 3:14
  • 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
    Commented Jun 1, 2016 at 3:26

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