Editing 2710: Hydropower Breakthrough

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==Explanation==
 
==Explanation==
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In this comic, [[Beret Guy]] announces that a {{w|hydroelectric dam}} has reached "Q > 1". This has two possible meanings, and the humour comes from their juxtaposition.
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{{incomplete|Created by a PRACTICAL WATER REACTOR. Do NOT delete this tag until the year 2039, or until fusion reactors have succeeded.}}
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The comic parodies fusion reactors, a form of electrical generator that typically aims to take in deuterium and tritium, then outputs helium and massive amounts of power. However, maintaining a fusion reaction is notoriously difficult, and for the longest time fusion reactors required external power to keep running, substantially more than they give back. In the past years, constant developments in fusion reactors have slowly increased the energy output of fusion to more than the input. It is possible this is meant to directly parody the Department of Energy's anticipated announcement of Q>1 fusion. The announcement is scheduled for the day after this comic's release, and [https://www.washingtonpost.com/business/2022/12/11/fusion-nuclear-energy-breakthrough/ the date of this was itself revealed] the day before this comic went up.
  
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In fluid dynamics, the letter Q represents the {{w|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.
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A {{w|hydroelectric dam}} is a power facility that generates electricity from water flowing in a river passing through a water turbine and generator. In the comic, [[Beret Guy]], unscientific as always, presents a hydroelectric dam. However, instead of generating energy, it generates a flow of water. This is similar to the way that a fusion reactor takes energy (and hydrogen isotopes) as an input and energy (and helium isotopes) as outputs. While one member of the audience shouts "Hooray!", another member of audience, who is presumably familiar with regular physics, says "Wait.", presumably because they realize that, instead of the normal approach, Beret Guy has been pursuing the essentially useless goal of producing more water. Or possibly because they're confused that, on the face of it, it appears to be violating {{w|conservation of mass}}, which would usually require 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, but such sources would typically also inveigle themselves into the undammed version of the watercourse under otherwise fully-saturated circumstances.
  
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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 {{w|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 [https://www.washingtonpost.com/business/2022/12/11/fusion-nuclear-energy-breakthrough/ 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}}
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If you only regard a limited time interval, a dam releasing temporally more water than is fed into it, can occur naturally, especially seasonally (stored water is released during a dry period) or accidentally (a dam break). The title "breakthrough" could be interpreted that way, making Beret Guy's announcement the opposite of a joyous occasion.
  
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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.
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It is possible — likely, even, considering Beret Guy's quasi-supernatural nature and regular violations of physical law — that his dam ''is'' violating conservation of mass and creating water through magical means. It is also possible that the dam contains direct energy-mass conversion technology, and is converting input energy into mass. In this case, the dam would be quite useless as a power plant, and would in-fact consume more energy than many entire countries. If the dam is not magical, it is possible that the dam is powered by {{w|zero point energy}}, something that Beret Guy has shown competence in handling (see [[1486: Vacuum]]).
  
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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 {{w|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.
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The symbol Q is normally used to refer to {{w|fusion energy gain factor}}, the ratio of power generated by a fusion reactor to the energy used to maintain it. An energy source isn't useful if it takes more power to run it than it produces, so Q > 1 means the reactor is producing net energy. Q also can represent the volumetric flow rate of water through a hydroelectric dam, and in this case, a Q > 1 would have no great significance. Beret Guy has somehow mixed the two up, making the rate of flow as the output of the reaction and increasing it.  
  
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The title text further confuses the issue by equating the hydroelectric dam with a {{w|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.
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The title text further confuses the issue as it introduces nuclear ''fission'' and equates the hydroelectric dam with a heavy water reactor, which is a special type of nuclear fission reactor that uses deuterium oxide (heavy water) as a moderator to absorb neutrons. This is also a pun because one could simplistically say that a hydroelectric dam runs on the weight of water (potential energy stored in the water: U = mgh), or that it is a water reactor (producing electricity) that is heavy (bulky). While a hydroelectric power plant is not actually a reactor, it would have to be using a reaction (such as 2H<sub>2</sub> + O<sub>2</sub> -> 2H<sub>2</sub>O) to create water to satisfy Beret Guy's statement that more water is produced than fed into the dam, while simultaneously satisfying the law of conservation of mass. Alongside that, the title text is possibly making a pun on water and fusion reactors. Heavy water is the primary source of deuterium, a specific isotope of hydrogen required for the most energy-efficient fusion reactions needed today. On the other hand, water is the liquid that passes through dams, and is rarely used for fusion reactions today — although [https://what-if.xkcd.com/14/ it could be used as fusion fuel because it is made of hydrogen and oxygen.]
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The title is probably also part of the joke in that hydro could be referring to water or HYDROgen [sic].  The hydrogen is presumably the fuel for fission.  The name "hydrogen" itself means "water maker" from the roots "hydro-" and "-gen".
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On 29 November 2022 Adam Selipsky CEO of Amazon Web Services (AWS) (A large Cloud provider and IT department of the Amazon webshop) announced in his Re:Invent (an annual congress for AWS customers where AWS announced new services and roadmaps) keynote that AWS will become water positive by 2030, he explained that AWS by then will produce more water than it consumes.
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[https://www.mobileworldlive.com/featured-content/top-three/aws-ceo-makes-water-sustainability-pledge/amp/]
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(video recording is available of it as well on a different website)
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This might have inspired the cartoonist to make a water positive dam.
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A way to create more water than one consumes can be by using hydrogen and take out part of the energy via a reaction with Oxygen in the air, like Hydrogen cars do. As AWS wants to be energy carbon neutral by 2025 and uses wind and solar power, a way to have energy available during times when there is not enough solar and wind is to store energy in hydrogen during times when there is too much, then 'burning' that hydrogen at scarce moments.
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The output can then be distilled water. So it's important that the additional water that is created will not just be 'dumped' into the environment, since that can change the existing ecosystem which may be built upon water which contains certain levels of minerals and/or salts.
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This cartoon takes that as a first warning already by showing a dam containing the water in a natural environment.
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AWS is an IT provider with hundreds of data centra, with many millions of computers. These typically use water to cool the computers. This cooling water heats up, energy can be extracted via a heat pump and be re-used. Sometimes (this doesn't have to be the case for AWS) this water is actually dumped when the water is not hot enough for the heat pump, and not cool enough to cool the machines.
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Sometimes the heat is used to heat houses or greenhouses.
  
 
==Transcript==
 
==Transcript==

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