Editing 2710: Hydropower Breakthrough

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==Explanation==
 
==Explanation==
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 - Needs another citation for the anouncment since the one that was present required a subscription to a paper! Do NOT delete this tag until the year 2039, or until fusion reactors have succeeded.}}
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The comic parodies fusion reactors, with energy produced seemingly never positive. 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 comics release, and the date of this announcement was announced the day this comic went up. {{citation needed}}
  
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 realise 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).
  
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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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.  
  
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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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 (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.]
 
 
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.
 
 
 
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.
 
  
 
==Transcript==
 
==Transcript==

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