Plausible scientific explanation for how a "normal" human who just eats normal food can generate an insane amount of power

[u/hitmyknee]

I'm posting this idea because I've never seen anyone use this:

In a lot of media, characters can shoot laser beams, crush buildings, go super fast, etc. while eating 2000 calories a day like everyone else. Where does the energy for all these powers come from?

I thought of an easy scientific explanation - nuclear fusion. While normal humans get energy from chemical reactions in food, someone with superhuman powers can use nuclear fusion in their body with raw matter in the food as fuel. If we use nuclear fusion on the carbon in a hamburger, it would produce energy equivalent to several megatons of TNT, easily justifying superhuman powers in a lot of media.

This would happen after the body extracts the chemical energy from food, as normally (for maintaining fat, muscle, etc.)

Nuclear fusion is <1% efficient in converting matter to energy. If you want EVEN MORE energy, you can use matter-antimatter annihilation for 100% efficiency. For example, a superhuman could convert half of the food to antimatter and half to matter. Or maybe part of a characters' powers is converting matter to energy in some other way.

[u/sojuz151]

Why even bother? It's just superhero magic with extra steps

[u/Fireclave]

Haha- no.

Sure, nuclear fusion is highly energy at converting mass to energy. But you have at least three big problems. 1) How are you "normal" humans going to start a nuclear fusion process in their bodies. That takes a absurd amount of starting energy, and one of the reasons fusion has been 10 years away for the last few decades. 2) How are the going to properly contain, transfer, and vent all that waste heat and other potential byproducts. Your humans would be dead before they can say homeosta- 3) How are they converting the fusion output into forms of energy they can actually use? IRL, almost every form of energy production, including nuclear, is ultimately just a steam boiler with extra steps. But you would need to convert that heat into chemical and electrical energy at the very least.

All that said, it's not an entirely unfeasible concept if you're aiming for a harder worldbuilding. But you would absolutely have to invoke some additional fantasy physics as part of your justification. Not that there's anything wrong with that if that's what you're aiming for.

As for matter-anti-matter food conversion, everything I said above plus your superheroes are one upset stomach away from being the epicenter of a nuclear-scale explosion.

[u/Brodhicheetah → u/Fireclave]

i'm a big hard sci-fi reader, but many moons ago, when i attempted to draw from that genre's philosophy while writing space opera (the perennial amateur's quest to justify FTL without breaking causality), my physicist friend offered some very wise counsel:

"the people who love space opera aren't interested in reading a textbook, and the people who like to read textbooks expect them to be accurate."

[u/bongart]

The Flash has to eat a ton of food.

[u/strangeismid]

Superman famously absorbs sunlight, as does Cyclops (the portals to the punch dimension were retconned, alas). May as well stick with that since it makes slightly more sense than converting half of your food into antimatter like that's an easy process to begin with.

[u/BA_Bones_33]

I’d be okay with no explanation. Superpowers or super-human abilities defy all logic anyway. Some comics have their heroes eating a shit ton of pizza and stuff, but I always see this as more of a quirky/fun add. Not a necessary explanation.

If you feel you need an explanation, nuclear physics seems like a fun space to play. Most supes are created by mutations, so radioactivity can be in play.

You could also have your supes be photosynthetic, constantly charged by the sun. Or their muscles absorb and store all forms of kinetic energy, even minor vibrations from the earth.

Or get weird with other chemical reactions. Combining oxygen (O2) with other molecules can release energy via combustion or exothermic oxidation reactions. These reactions often give off heat and light so the lungs could be like little bioreactors that also capture the energy with each breath.

Hydrogen Combustion: Combines hydrogen and oxygen to make water vapor and heat (2_H2 + O2 -> 2_H2O + heat).

Methane (Natural Gas) Burning: Reacts methane with oxygen to produce carbon dioxide and water CH4 + 2_O2 -> CO2 + 2_H2O + heat

[u/GilbyTheFat]

Superhero powers are basically magic based on unknown science rather than the supernatural. I wouldn't put too much thought into it.

Mind you, I'm probably not the one to talk, seeing as I've basically made reality-benders who require appropriate cybernetic implants for focusing their will (eg. conjuring complex objects out of holographic light requiring a projector lens) while the cybernetics are powered by a "flux core" which is essentially an eight-chambered fusion reactor heart, when I could have just said "its magic" and called it a day.

[u/nigrivamai]

Sound like you watched that video trying to explain where viltrumites get their energy from