How much is 3 gigajoules per second? In the first movie he made a small reactor and said that's how much energy it produces. What I want to know is the science behind that kind of power. What it would be equivalent to if it's possible to make maybe not that small but anything at all that can make that kind of power? He made it in a cave with scraps from a rocket that would take probably billions and then some to make something that powerful but bigger what is something we have that could potentially make something that strong like power plants plutonium plasma I need some science people on this question please and thank you :)

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    Welcome to SFF.SE, 3 gigajoules per second = 3 gigawatts. Your question is likely to be closed if you're seeking a scientific explanation for this.
    – Voronwé
    Sep 26, 2018 at 2:45
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    Well, clearly you need a cave and scraps from a rocket. I feel like you've answered your own question.
    – Misha R
    Sep 26, 2018 at 6:00
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    It's about 3 times as much as "one-point-twenty-one-jigga-watts". ;^)
    – DrSheldon
    Sep 26, 2018 at 19:14
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    Comic book physics isn't real-world physics. Sep 26, 2018 at 22:00

1 Answer 1


3 GJ/s (gigajoules per second) is an average of 3 gigawatts - that is, 3 billion watts.

How much is that, you ask? Oh, well, about the largest power plants you'll find run at 1 GW.

To put it another way, 3 GW is about 2/3 the power output of the entire Fukushima generating complex.

So, the last thing you need is some science people on this. They will uniformly shake their heads and tell you you can't do it.

As a for instance, let's say the reactor works with 99% efficiency - something which simply doesn't happen. That means that 1% of the output will be in the form of heat. That's 30 MW (megawatts) of heat energy being produced inside Tony Stark's chest. As a reference point, Anglesey Aluminum, a British plant which produced 144,000 tons of aluminum per year, needed 255 MW, so you've got the heat output of a small (15,000 tons/year) smelter being cooled by Tony's blood. That will work for a (very small) fraction of a second before he explodes into a cloud of steam and flesh fragments.

So basically, you need a reactor composed entirely of unobtanium and cooled by massive amounts of handwavium.

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    Reminds me of the suit Tony put together in the 1970s. Normally, it was like a t-shirt briefs; when activated, it turned into his armor, sliding the sleeves/leggings/helmet over him into place. Someone calculated that, at the speed stated, Tony would be at least hairless, and would probably have 2nd-3rd degree burns on his arms and legs.
    – RDFozz
    Sep 26, 2018 at 17:23
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    Ah that elusive element handwavium. A very important component in fuel for ships dashing across space-time to save the protagonist in dire need of saving. It only seems to work under these circumstances however.
    – Neil
    Sep 27, 2018 at 8:53

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