2710: Hydropower Breakthrough

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Hydropower Breakthrough
A hydroelectric dam is also known as a heavy water reactor.
Title text: A hydroelectric dam is also known as a heavy water reactor.


In this comic, Beret Guy announces that a hydroelectric dam has reached "Q > 1". This has two possible meanings, and the humour comes from their juxtaposition.

In fluid dynamics, the letter Q represents the volumetric flow rate, or volume of fluid per unit time, e.g. m³/s. Depending on the units chosen, it would not be at all surprising for this number to be greater than 1 for a hydroelectric dam.

However, Beret Guy's clarification, that the meaning of this is that the dam is producing more water than was fed into it, suggests that he is interpreting the letter Q in a manner similar to its use in fusion power, where it represents the ratio of output power to input power. Typically fusion reactors require more power than they generate, but on the day after this comic was released, the US National Ignition Facility announced the first Q > 1 fusion reaction. However, hydroelectric dams work quite differently from fusion reactors,[citation needed] and (despite frequent comparisons) water is different from electricity.[citation needed]

If a dam were indeed producing more water than came into it from the reservoir and other sources, especially on a consistent basis (and not just because of water that had been stored somehow inside the dam) it would be a violation of the law of conservation of mass. It appears that one of the audience members is oblivious to this fact, joining in Beret Guy's celebration, while another audience member is more effectively applying their critical thinking skills.

Alternatively, it is possible that Beret Guy is suggesting that the amount of water coming out of the dam is greater than the amount travelling into it via the penstock. If so, this indicates that water is finding other paths through the dam (a literal "breakthrough"), which is a very dangerous situation and would also be a cause for concern, not celebration.

The title text further confuses the issue by equating the hydroelectric dam with a heavy water reactor, which is a type of nuclear fission (not fusion) reactor that uses deuterium oxide, or "heavy water", as a moderator. A hydroelectric dam is powered by the weight of water, but it is not a reactor.


[Beret Guy is standing on a podium behind a lectern. He is gesturing with his hand, palm up, towards a poster hanging behind him. On it is a picture of a tall dam, with a lake behind, and water coming out at the foot of the dam in the valley on the other side. Two voices reacts to Beret Guy's statement from off-panel.]
Beret Guy: We are pleased to announce that our hydroelectric dam has achieved Q>1, producing more water than we fed into it!
Off-panel voice 1: Hooray!
Off-panel voice 2: Wait.

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ChatGPT sez:

The comic depicts Beret Guy, a character known for his expertise in science and engineering, standing on a podium and announcing that their hydroelectric dam has achieved a level of efficiency greater than one, producing more water than was fed into it. This is cause for celebration, as it indicates that the dam is functioning properly and efficiently. However, the second off-panel voice raises a question, suggesting that there may be more to the situation than initially thought.
The title text adds further information by revealing that a hydroelectric dam is also known as a heavy water reactor. This suggests that the dam may not be operating in the traditional way, but rather may be using a different type of technology, such as nuclear power, to produce the excess water. This could raise concerns about safety and the potential risks associated with this type of technology.

Meh. 03:44, 13 December 2022 (UTC)

It *is* possible. All Beret Guy has to do is use the electricity to run air conditioners, which will have one side condensing water from the atmosphere, ergo more water coming out than went in. SDSpivey (talk) 04:00, 13 December 2022 (UTC)

I think there's a conservation of energy violation here, but can't model the entire system. 14:31, 13 December 2022 (UTC)

Considering that he phrases it "more water than we fed into it" in the past tense, it might just be that there's a leak in the dam. 04:06, 13 December 2022 (UTC) mraction

More variation: "more water than *we* fed into it" ie not counting water from the river that feeds it, or rainfall. There's also the title text turn of phrase "heavy water reactor". "heavy" could refer to either the "water" (in the sense of gravity, or deuterium passing through), or the "reactor" (as in its mass) - 05:43, 13 December 2022 (UTC)

A fusion reactor that produces more energy than it consumes does so by consuming and producing things other than energy. If they're running a hydrogen gas turbine at the site, they could be producing more water (from hydrogen and oxygen gases) than they lose, at least in theory. Of course, producing and shipping hydrogen to the site of a dam would be vastly less efficient under any reasonable circumstances than producing electricity instead of hydrogen in the first place. 07:34, 15 December 2022 (UTC)

If Q is only barely >1 it could square the circle by converting atoms to oxygen by fusion in order to create water but the whole energy of the dam is used to make the fusion of a few oxygen atoms.

"Another member of audience, who is presumably familiar with regular physics, says "Wait.", because conservation of mass usually applies to water such that a dam should produce the same amount of water as that fed into it. That said, for a regular dam in a natural valley like the one shown in this comic, it is entirely normal for the dam to "produce" more water than input in the sense that in addition to water from upstream rivers, the dam will also output any "unofficial" inflow from direct rainfall above and from uncharted sources of groundwater below."
I thought that the "Wait" comment was in relation to the fact that the announcement, although achieving something that was not achieved so far, is impractical. As the power plants are expected to produce energy, announcement that they produce additional water is irrelevant, and the "wait" comment indicated that they have missed the point. (talk) (please sign your comments with ~~~~)

Given the title of Hydropower Breakthrough, is a possible interpretation that the dam is just about to fail? -- 10:35, 13 December 2022 (UTC)

My immediate thought was that he was using the generated electricity to ignite a hydrogen cell, but my immediate thoughts are always weird. 14:31, 13 December 2022 (UTC)

I feel Randall's comic is strongly indicative of a fair degree of skepticism around recent fusion power hype (many existing fission reactors produce an energy surplus, but fail to meet their cost of operations)... Yet, the comic's explanation currently reads as a guileless exhortation of fusion's possibilities, making no mention of the many other challenges faced by fusion reactors, besides this critical first step of generating more power than required to sustain the reaction. The comic is clearly making light of the recent publication\marketing push, yet the explanation gives no sign that fusion power is anything but practical & just around the corner. Fusion still has many remaining challenges to overcome, before reaching practicality as an energy source even for military applications (moreso still, for public utility); wind & solar are the top KWh:$ producers & another 10 or 100 billion spent researching fusion are very unlikely to change that in the next couple decades. In fact, solar research returns more Watts per dollar. The comic should probably mention the other challenges involved in nuclear fusion power, besides raw output quantity? ProphetZarquon (talk) 16:00, 13 December 2022 (UTC)

Top KWh:$ producers sure, by which statistics? The effectivity of different kinds of power plants varies widely both with specific location, cost of input and the method used, but usually the hydroelectric damns build in good terrain would take a lead, especially considering that they can work for more than century. Which wind or solar power plant can hope for that? There is sure lot of research still necessary to make fusion power plants reality, but long term it can easily pay itself, and it can work anywhere, while damns need to be build on river, wind onshore (offshore are MUCH less effective and no research will change that) and solar, well, not too far from equator and somewhere with sunny weather, it wouldn't work when raining. Or, well, in space. Fission might also get good value from research if the research actually will be happening. -- Hkmaly (talk) 23:21, 13 December 2022 (UTC)
Dams are far from maintenance free & damage local ecologies in ways which can't yet be solved (a fish run lessens only one of these issues & only partially), plus they cost way more per watt-hour to deploy. Also, the turbines they rely on, require periodic service similar to those used with wind. More importantly though, dams & solar & wind are already a viable method of public energy production, & research into improving solar & wind return far more improvement in watt-hours per dollar, than nuclear does. Since we're already in the midst of a growing ecological crisis & need cleaner energy now, it makes more sense to research solar & wind, than nuclear. Sure, nuclear energy research may pay off eventually, but we need society to survive long enough to benefit; solar & wind make money and energy, right now, & research money spent on solar & wind power has returned far more Watt-hours per dollar, than research into nuclear power. Also, it's very incorrect to presume that solar only works well at low latitudes: Solar is used extensively in nordic regions, & even the energy-per-meter landing at the Earth's poles is still quite significant; there's so much energy in solar power, that it's almost ridiculous to go looking elsewhere. I agree that some forms of nuclear energy deserve more research funding than they've received so far (US-funded research is so obsessed with highly-fissile materials, that even nuclear energy "experts" are often ignorant of other methods), but at this point future technologies like fusion & hydrogen power, are effectively siphoning money from tech that would help now in favor of speculation on tech that could help someday. Money spent researching fusion isn't necessarily wasted, but spending that money to research solar or wind, helps more people sooner, while we have increasingly little time left to do so.
ProphetZarquon (talk)

21:07, 15 December 2022 (UTC)

Moreover, my point is that Randall’s comic seems to portray this type of fusion hype as somewhat laughable, yet the comic's explanation treats fusion as a serious current contender for public utility; which it simply isn't (not for another few decades at the earliest, anyway). I feel the explanation fails to convey the absurdity prompting the "Wait..." reaction: The findings are presented with such overblown hype, that a reasonable attendee finds it obvious that something isn't as it's presented. A more responsible explanation might begin by stating outright, that fusion energy as a utility is a long-term possibility, but is not "on the verge" of near-term viability, despite findings massaged to attract further speculative finance.
ProphetZarquon (talk) 21:34, 15 December 2022 (UTC)

I think the explanation is overthinking it. The joke is that there's a leak in the dam. An idiot (talk) 16:37, 13 December 2022 (UTC)

You mean you only see one of the long list of jokes in this comic? -- Hkmaly (talk) 23:21, 13 December 2022 (UTC)
I guess my mind just thought of the simplest joke first? :shrug: -- An idiot (talk) 06:03, 14 December 2022 (UTC)

The explanation says nothing about the effect this would have downriver from the dam. Inquirer (talk) 16:51, 13 December 2022 (UTC)

I wonder if the image depicts Vajont Dam, https://en.wikipedia.org/wiki/Vajont_Dam, which was overtopped by a massive wave generated by a landslide--briefly outputting MUCH more water than was input. 18:38, 13 December 2022 (UTC)

Is not counting rain, equivalent to only counting the energy released by the laswers, not the energy fed into the lasers? Arachrah (talk) 20:47, 13 December 2022 (UTC)

Another possible reason for the "Wait." comment is that, if Beret Guy's dam is indeed magically creating water, then left unchecked it could, over time, lead to the sea levels rising higher than all land surface on Earth. This would indeed be a very unfortunate situation. Dansiman (talk) 22:24, 13 December 2022 (UTC)

One of the things I just edited out was the claim that discharging (effectively) distilled water could dehydrate the environment. With an unnaturally hypertonic (dilute) water-source, creatures would not dry out but (if anything) absorb more water under osmotic pressure, which could lead to cells bursting from too much effort to balance things out. Hypotonic water (too many salts, for a given organism) would draw cellular/bodily stores of water out. Probably a 'pure water discharge' of the kind described would locally dilute the natural body of water that it was set to run into, but would also fairly quickly make itself/its dump-body more eager than normal to adopt ions from the immediate geologies of the run-off path. If you don't presume deluging a parched land with basically your fancy new-water output, there might be effects upon plants and animals adapted to more hard and/or briney water-environments (e.g. creating a disruptive freshwater lagoon within a saltwater marsh), with some ecological concerns to be addressed by careful use of mixing ponds (almost the opposite of most waste-water outlettings, which may require settling ponds or filtrating reed-beds) and questions about relative temperatures (which can be useful or disruptive to the survival of local creatures who might previously have migrated to more naturally warmer expanses of water), but overall it'd be better than most post-industrial water outflows. With the right eco-oversight to spot side-effects. 01:39, 14 December 2022 (UTC)

Where did all the AWS advertising come from? The comic has no relation to cloud computing or the amazon. The companies green washing ads should be deleted. -- 09:30, 14 December 2022 (UTC)

Twelve paragraphs is absurd. This wall of text is an order of magnitude harder to understand than the simple comic joke. It needs to be trimmed to three to five paragraphs, tops! 00:16, 15 December 2022 (UTC)

Agreed, but it was that large by the time I arrived at the article, and it seemed that two (or three) separate strands of thought had been separately composed and concatonated. Perhaps not helped by multiple subtly different interpretations of the hidden meanings springing from deep within the words. Major re-editing is needed, but I'm not confident enough to blitz it properly. 00:39, 15 December 2022 (UTC)
Those single sentence paragraphs with no context. This is the worst post-start explanation I've seen in months. Now that the next comic is up it's time to get to work. 04:57, 15 December 2022 (UTC)

The AWS stuff should all be deleted. It is nonsensical. AWS uses water for evaporative cooling of its data centers. It is spending loads of money on wet lands to feel better about it. That has nothing what-so-ever to do with this comic.

ChatGPT may be only barely mediocre at producing good explanations from the transcripts, but it did a fantastic job of reducing 14 absurdly verbose to 5 simple paragraphs (8.3 to 3.6 kilobytes.) I did maybe fifteen words of cleanup, mostly to put the (wiki)links back in. 05:19, 15 December 2022 (UTC)

The explanation makes it seem like we may already have fusion reaction net energy gain, when this is simply not the case: we may have achieved Q > 1 for the energy put into the hydrogen particle, but this disregards the energy required to power the lasers as well as the energy required to convert the resulting heat into electricity (that would be QTotal > 1). 13:07, 15 December 2022 (UTC) Gogeta

I'm wondering if this is also relevant to Amazon's claim that their data centers somehow have 1:1 water cooling consumption:production, with a future predicted ratio that is somehow "even higher". 00:44, 16 December 2022 (UTC)

Is it not Q>I, rather than Q>1? (talk) 03:42, 28 April 2024 (please sign your comments with ~~~~)

You'd need to justify what the "I" could be. (Noting that even in 2707: Astronomy Numbers, the 'simple' digit one features as well as the serifed/tick-marked version for a stylistic digit, but (generally) xkcd "|"s serve as both numeric and alphabetic glyphs.) And there's a clear joke regarding ">1", where there isn't really one here for ">I" without reason to believe it specifically references luminous intensity, moment of inertia, electric current, etc, although with some additional terms (that Randall'd know to use) you might be able to justify those equivalences... 13:01, 28 April 2024 (UTC)