Editing 2710: Hydropower Breakthrough

{{comic
| number    = 2710
| date      = December 12, 2022
| title     = Hydropower Breakthrough
| image     = hydropower_breakthrough_2x.png
| imagesize = 261x303px
| noexpand  = true
| titletext = A hydroelectric dam is also known as a heavy water reactor.
}}

==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.

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.

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}}

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 {{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==
:[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.

{{comic discussion}}

[[Category:Comics featuring Beret Guy]]
[[Category:Strange powers of Beret Guy]]
[[Category:Public speaking]]
[[Category:Physics]]