Stark's Arc Reactor Fuel Consumption

[Ted C]

Just did a quick number run on the arc reactor's fuel supply.

Assuming that it uses some variation of deuterium fusion and that the maximum output is 8 GigaJoules for one full load of fuel, it would only need about 13 milligrams of fuel to refill (at 100% efficiency).

I was surprised at how plausible it would be to power one of the Iron Man armors with such a small power supply. In fact, it's surprising that he ran low in The Avengers. Even if assume the peak output is 8 GigaWatts and he's running at that constantly, he should still be able to operate for hours on 1 kg of fuel (unless the efficiency is a lot lower than 100%).

[Elheru Aran]

I think that perhaps part of the situation in Avengers could have been that he didn't refuel in between his first deployment against Loki, the fight between him and Thor and Cap, then the Hulk confrontation, before he finally went down to Stark Tower before the last big battle. If the Iron Man suit consumes power at an increased rate,

Another option is that he doesn't normally refuel very often, and we're seeing him go from the 1/4 tank level to the fill-up light. It's also quite possible that he can't always come by a whole kilo of deuterium to fuel up in full, so perhaps he buys a large lot of it at a time and then portions it out as he needs it.

Out of curiosity, where are you getting your numbers?

[Eternal_Freedom]

I think that perhaps part of the situation in Avengers could have been that he didn't refuel in between his first deployment against Loki, the fight between him and Thor and Cap, then the Hulk confrontation, before he finally went down to Stark Tower before the last big battle. If the Iron Man suit consumes power at an increased rate,

Whilst that is true, he did switch to the new armour suit after getting thrown out of the window, and whilst he didn't refuel his chest reactor, the Mark VII (or VIII, whichever it was) clearly had it's own power source that let it fly out to meet him.

[Elheru Aran]

I think that perhaps part of the situation in Avengers could have been that he didn't refuel in between his first deployment against Loki, the fight between him and Thor and Cap, then the Hulk confrontation, before he finally went down to Stark Tower before the last big battle. If the Iron Man suit consumes power at an increased rate,

Whilst that is true, he did switch to the new armour suit after getting thrown out of the window, and whilst he didn't refuel his chest reactor, the Mark VII (or VIII, whichever it was) clearly had it's own power source that let it fly out to meet him.

That's true, but as it had no arc reactor of its own (IIRC) probably it's only a battery of some sort. Even the most advanced batteries we have currently would be hard pressed to power something as bulky as an Iron Man suitcase-suit through flight for the seconds we see it in action before it wraps itself around Tony. I see no reason to assume it would have added much to Tony's own power supply, if any.

[Ted C]

I think that perhaps part of the situation in Avengers could have been that he didn't refuel in between his first deployment against Loki, the fight between him and Thor and Cap, then the Hulk confrontation, before he finally went down to Stark Tower before the last big battle. If the Iron Man suit consumes power at an increased rate,

Another option is that he doesn't normally refuel very often, and we're seeing him go from the 1/4 tank level to the fill-up light. It's also quite possible that he can't always come by a whole kilo of deuterium to fuel up in full, so perhaps he buys a large lot of it at a time and then portions it out as he needs it.

Out of curiosity, where are you getting your numbers?

I was going by a description on the Marvel wiki, but checking quotes at IMDB, it appears that the Mark I reactor had an upper limit of 3 GW, and he expected it to be able to run at full output for about 15 minutes. Of course, when you're working in a cave, from a box of scraps, you can't expect to have much fuel lying around.

The Mark II reactor certainly had a greater capacity, too.

[Ted C]

Whilst that is true, he did switch to the new armour suit after getting thrown out of the window, and whilst he didn't refuel his chest reactor, the Mark VII (or VIII, whichever it was) clearly had it's own power source that let it fly out to meet him.

That's true, but as it had no arc reactor of its own (IIRC) probably it's only a battery of some sort. Even the most advanced batteries we have currently would be hard pressed to power something as bulky as an Iron Man suitcase-suit through flight for the seconds we see it in action before it wraps itself around Tony. I see no reason to assume it would have added much to Tony's own power supply, if any.

The Mark VII armor, when launched, has a plainly visible arc reactor built into its chest piece even before it catches up with Tony. While his personal reactor might be running low on fuel, the Mark VII suit should have a full tank.

[Eternal_Freedom]

Ted C, he said it had a maximum of 3 GJ, not GW, and that it would power the suit for 15 minutes, meaning the scrap-suit was pulling 3.3 MW. Apparently that Mk I reactor was about half as powerful as the one that Obadiah nicked, as JARVIS said power was at 49% when the Mk1 reactor was used with the new improved armour suit.

And then in IM2, the new element gave him "significantly increased power levels" according to Romanov, so that's another jump in power for the arc reactors.

[Lord Revan]

Whilst that is true, he did switch to the new armour suit after getting thrown out of the window, and whilst he didn't refuel his chest reactor, the Mark VII (or VIII, whichever it was) clearly had it's own power source that let it fly out to meet him.

That's true, but as it had no arc reactor of its own (IIRC) probably it's only a battery of some sort. Even the most advanced batteries we have currently would be hard pressed to power something as bulky as an Iron Man suitcase-suit through flight for the seconds we see it in action before it wraps itself around Tony. I see no reason to assume it would have added much to Tony's own power supply, if any.

The Mark VII armor, when launched, has a plainly visible arc reactor built into its chest piece even before it catches up with Tony. While his personal reactor might be running low on fuel, the Mark VII suit should have a full tank.

it seems that By the time of IM2 all of Tony Stark's "spare" suits had an arc reactor installed in them, it was reason the War Machine armor could be used after it was "confiscated" By the US military as neither the US goverment or Hammer had figured out the secret of the arc reactor at that point.

[Ted C]

Ted C, he said it had a maximum of 3 GJ, not GW, and that it would power the suit for 15 minutes, meaning the scrap-suit was pulling 3.3 MW.

Yeah, I saw that when I went searching for the exact quote. According to IMDB's quotes from the movie, it could produce 3 GJ/s for fifteen minutes, so it's not actually 3.3 MW. 3 GW for 15 minutes would be 2.7 TJ.

Assuming 100% energy efficiency, that would require a little over 4 grams of fuel. Even with pretty low efficiency, that's still not much fuel (assuming that it's doing some kind of deuterium fusion).

Apparently that Mk I reactor was about half as powerful as the one that Obadiah nicked, as JARVIS said power was at 49% when the Mk1 reactor was used with the new improved armour suit.

And then in IM2, the new element gave him "significantly increased power levels" according to Romanov, so that's another jump in power for the arc reactors.

So the newer ones are probably generating several GW at peak output, but even then it wouldn't take a large mass of fuel to run the suit for hours.

[Eternal_Freedom]

Isn't it supposed to run on palladium? I recall him saying he needed 1.6g for the first one he built, and he was changing over cartidges of palladium in IM2.

[Ted C]

Isn't it supposed to run on palladium? I recall him saying he needed 1.6g for the first one he built, and he was changing over cartidges of palladium in IM2.

Palladium is a necessary component, but I don't think it's the fuel.

[Elheru Aran]

The Mark VII armor, when launched, has a plainly visible arc reactor built into its chest piece even before it catches up with Tony. While his personal reactor might be running low on fuel, the Mark VII suit should have a full tank.

A full mea culpa on that, then. There's no real reason Tony should have had run out of fuel in that case unless for some reason the Mk VII consumed fuel at a higher rate in action or some such bollocks.

[Gandalf]

Isn't it supposed to run on palladium? I recall him saying he needed 1.6g for the first one he built, and he was changing over cartidges of palladium in IM2.

Palladium is a necessary component, but I don't think it's the fuel.

In IM2, he was apparently depleting the palladium cores from his reactor.

[Eternal_Freedom]

The Mark VII armor, when launched, has a plainly visible arc reactor built into its chest piece even before it catches up with Tony. While his personal reactor might be running low on fuel, the Mark VII suit should have a full tank.

A full mea culpa on that, then. There's no real reason Tony should have had run out of fuel in that case unless for some reason the Mk VII consumed fuel at a higher rate in action or some such bollocks.

Well he was trying to use those wrist laser things to burn through the flying thing's armour, and in IM2 they were a one-shot weapon. That probably drains a lot of energy. Plus the entire battle was probably a lot more intense than his usual fights.

[Havok]

It has it's own juice, which is why it ejects when it's own power is spent, otherwise it would just stay on his wrist.

Also, the suit change in The Avengers isn't because of power, it's because of damage. Each suit has it's own arc reactor which you see when he gets to his storage locker on the helicarrier and we can also infer based on War Machine/Iron Patriot, as Rhodey obviously doesn't have a built in arc reactor and from the fact that all the suits in Iron Man III run at full power by remote control.

[Eternal_Freedom]

Does he eject it in Avengers? I know he did in IM2, but I can't recall if it was a one-shot thing by the battle in New York.

[Terralthra]

Does he eject it in Avengers? I know he did in IM2, but I can't recall if it was a one-shot thing by the battle in New York.

Well, Jarvis says "We will run out of power before you penetrate its skin", rather than "your laser will run out of its power", so presumably the Mark VII has an integrated reusable laser, rather than a one-shot.

[Simon_Jester]

Ted C, he said it had a maximum of 3 GJ, not GW, and that it would power the suit for 15 minutes, meaning the scrap-suit was pulling 3.3 MW. Apparently that Mk I reactor was about half as powerful as the one that Obadiah nicked, as JARVIS said power was at 49% when the Mk1 reactor was used with the new improved armour suit.

3.3 megawatts is actually quite high for making an object that sized move. You really shouldn't need more power to power the Mark One than you would to power, say, a car.

Then again, Stark may not have meant the reactor would only last fifteen minutes, speaking rhetorically or informally. Fifteen minutes would be kind of problematic, in my opinion; it's not really enough time to be sure of getting clear of the EVIL TERRORIST lair. Even with the jump-jet rockets, the distance you can fly in that time isn't far enough to be sure of outrunning or evading pursuit.

As it happened, Stark caused enough damage to the base on his way out that no one was in any position to chase him, but could he have counted on that?

And then in IM2, the new element gave him "significantly increased power levels" according to Romanov, so that's another jump in power for the arc reactors.

Yeah, but he seems to have taken advantage of the increased power output with more power-hungry weapon systems (particularly the laser)

The Mark VII armor, when launched, has a plainly visible arc reactor built into its chest piece even before it catches up with Tony. While his personal reactor might be running low on fuel, the Mark VII suit should have a full tank.

A full mea culpa on that, then. There's no real reason Tony should have had run out of fuel in that case unless for some reason the Mk VII consumed fuel at a higher rate in action or some such bollocks.

Well, he was fighting about as intensively as he'd ever fought in his life, for a period that may well have been hours long, making heavy use of his repulsors as both flight and beam weapons, and on at least one occasion breaking out the laser: "Sir, we will run out of power before we cut through that."

When he designed the suit, how long did he expect it to have to last in action without a time-out to recharge his batteries? It may be like aircraft, where for reasons of weight savings they just plain don't have fuel to stay on station in combat for more than an hour or two, especially if they have to make intense maneuvers to avoid enemy fire.

It has it's own juice, which is why it ejects when it's own power is spent, otherwise it would just stay on his wrist.

I figured it was channeling suit power, but the emitter burns itself out because it's not cooled very effectively. That's why the cartridge for the laser cannon is smoking when it ejects.

Also, the suit change in The Avengers isn't because of power, it's because of damage. Each suit has it's own arc reactor which you see when he gets to his storage locker on the helicarrier and we can also infer based on War Machine/Iron Patriot, as Rhodey obviously doesn't have a built in arc reactor and from the fact that all the suits in Iron Man III run at full power by remote control.

This is true. On the other hand, it does at least confirm that all the fights he got into in the Mark Six should not have affected his 'battery lifetime' in the Mark Seven once he got that on after threatening Loki.

[Eternal_Freedom]

I can't imagine he would build suits build for long-duration combat before Avengers, since all he does is fight people on Earth with close-to current Earth tech, certainly nothing in his league. Avengers was really the first time he had to go up against large scale forces (which probably also never happened before) that were of a similar tech level.

[Batman]

Technically, Tony never said the reactor would only power the Mk i for 15 minutes, he said 'something big'. At that point he hadn't built the suit yet so even if he was already thinking about the power consumption of the eventual suit this might be nothing more than a rough order-of-magnitude guesstimate.
As for the fuel issue, while I doubt fuel 'weight' would be much of a concern fuel 'volume' might be. Or maybe not given Tony managed to cram several times the suit's volume worth of ordinance into it.

[Simon_Jester]

I'm a bit unsure about the volume of ordnance thing. For most of his shooting he was firing the repulsors which are energy weapons; where are you getting that from?

[Batman]

The amount of missiles he manages to cram into a suit not all that much bigger than himself, with himself in it so the volume that not all that much larger than life suit has available is decidedly limited.

[TOSDOC]

I think he's referring to the missle/ballistic weapons in the suit's shoulder at the start of the battle, and in the thighs when he pulls the Jonah maneuver. I'm not sure there's a discrepancy in volume compared to earlier suits with such, though, since the Mark VII appears bulkier in those areas already.

[Batman]

The damn Mk II already used volume it didn't have.That tankbuster missile from IM1? Have fun fitting that into the armour without removing Tony's lower arm.

[TOSDOC]

The damn Mk II already used volume it didn't have.That tankbuster missile from IM1? Have fun fitting that into the armour without removing Tony's lower arm.

I'm still wondering where you fit the tank in your car too, Bruce.