Ironman’s carbon footprint is a bit of a paradox: it’s simultaneously huge, and impressively small given how much energy and material he requires for his technologies.
Ironman is a hero in the Marvel Comics Universe and the alter-ego of billionaire-playboy-philanthropist Robert Downey Jr. Tony Stark. Ironman doesn’t really have any superhuman abilities. Instead, Stark builds incredible technologies like his Ironman suit to give him super strength, agility, and the ability to fly. Therefore, we’re going to examine the carbon footprints of each separate piece of Ironman’s arsenal.
Armor
Thankfully, my friend Ryan Haupt has already investigated the science of Ironman’s suit at length, finding many real-world analogs to a lot of the technology Ironman uses (Unfortunately, links to his work are no longer active, but here are some similar alternatives). For these carbon footprint calculations, I’m assuming that Ironman is using the Mark II or Mark III suit (the one he wears in the early movies).
A group of fans has already tried to estimate how much the Ironman suit weighs (because, of course they have). They came to the conclusion that it only weighs 250 lbs. That sounded light to me (and to Ryan as well). Then again, a medieval suit of armor weighed around 60 lbs so maybe 250 isn’t that far off. So what’s the suit made out of?
His armor is likely a derivation of nitinol, a self-healing metal, overlaying a bullet-proof Kevlar suit. To protect his feet from his rocket boots, he probably uses a carbon-carbon composite similar to that used on the space shuttle. All of this stuff Tony uses to build the Ironman suit has a carbon footprint based on the energy required to extract, build, and transport the materials. Based on these assumptions, a single Ironman suit has a carbon footprint of 131,081 lb CO2e.
But, from the comics and the movies, we know that Ironman never has just one suit. He’s probably working on at least three suits at any time, which makes Ironman’s carbon footprint from building his armor:
Emissions = 393,243 lb CO2e
Power – The ARC Reactor
One of Tony Stark’s most brilliant inventions that made Ironman possible was the ARC reactor – a clean(er) energy source that can deliver unbelievable amounts of power. According to my trusted Ironman source Ryan, the ARC reactor is a miniaturized nuclear fusion device (a device that fuses atoms together rather than splits them apart, as we currently do with nuclear fission reactors). In real-life, this very non-miniaturized experimental technology is called a tokamak reactor.
In theory, if it were similar to a tokamak, Ironman’s ARC reactor could extract nearly 95,000 kWh worth of energy from just one gram of material. That’s nine times more energy than the average American household uses per year extracted from something that weighs as much as a jelly bean.
Real-life tokamaks create energy from a fusion reaction between deuterium (which we can derive from seawater) and tritium (which we can derive from lithium). The cool part about this reaction is that we can use the clean(er) energy from fusion to process the raw seawater and lithium into the needed deuterium and tritium — meaning that we drastically cut the carbon emissions from processing.
As Ironman, Tony Stark builds a lot of cool gadgets and maintains a bunch of huge computers to help him navigate around the world, build stuff for his fellow Avengers, and interact with his incredible AI technology, JARVIS. He’s pretty much a one-man Google.
Google used 3,324,818 MWh of energy in 2010. Using an ARC reactor, Ironman would need around 14 kg of deuterium (derived from 123,368 gallons of seawater) and 21 kg of tritium (derived from 420 kg of lithium). Most of the planet is ocean, so presumably the seawater would be pretty easy to get. But the lithium would still require mining, meaning that Ironman would still release 174 kg-CO2e for every kg of lithium mined. This equates to a total carbon footprint from Ironman’s technology of:
Emissions = 161,114 lb CO2e
This is a stupidly small number for the amount of energy created and used. It means that Ironman releases only 0.0000485 lb-CO2e/kWh, which is more than 2,000 times cleaner than solar or nuclear fission technologies we have today. Bravo, Ironman! Bravo, indeed.
Flight
Flight might be one of the more contentious aspects of Ironman’s carbon footprint. The comics are clear that he uses “rocket boots,” which implies that he’s burning rocket fuel. Not surprisingly, this would have a bad carbon footprint. It’s also possible that Ironman uses something else to propel himself around: plasma. Plasma would have a much lower carbon footprint, and Tony Stark does want to singlehandedly save the world, so maybe he’s using this cleaner alternative.
If he’s burning rocket fuel, he’ll need around 9 gallons worth for a 1 hour flight, or 54 gallons for a flight from NYC to LA.
If he’s using a plasma rocket, he’s probably using something similar to the real-life VASIMR system. Plasma rockets don’t deliver a ton of thrust — they’re designed for long space voyages. Tony would need around 157 VASIMR rockets to fly, which would draw 31,429 kW of power (and weigh more than five T-Rexes).
So now we can compare the two systems:
It turns out, burning rocket fuel releases several orders of magnitude more carbon equivalent than the plasma system would. Though, to be fair, rocket boots would be slightly less impractical than strapping 157 plasma rockets to your back.
Weapons – Repulsor Rays
Ironman’s repulsor rays are directed projections of thrust. This would allow his repulsor rays to work from the same VASIMR technology Ironman uses to fly. From the comics and the movies, we know that a repulsor ray blast acts like a superhuman punch that can send enemies flying through the air. Boxers can punch with 450-1,500 lbs of force, but that’s not enough to send someone flying through the air. Let’s double it so that Ironman can deliver a big hit without necessarily killing his enemy.
If he’s blasting bad guys 20 times per adventure, then he uses 7,695 kWh of energy per year for his weapons. Therefore, the carbon footprint from his repulsor rays comes out to:
Emissions = 7,695 kWh * 0.0000485 lb-CO2e/kWh = 0.37 lb CO2e
The Final Analysis
Ironman’s total carbon footprint depends on what he uses to fly. If he uses true-to-their-name rocket boots, then he adds 145,000 lbs of CO2e when compared to the plasma-propulsion of the VASIMR system. So, overall, Ironman’s carbon footprint comes out to:
Emissions = 393,243(armor) + 161,114(Stark Industry Tech) + 0.37(Repulsor Rays) + 356-145,480(flight) = 554,713-699,837 lb CO2e
Truly, Tony Stark is a man of the future — building efficient and clean technologies to power his philanthropic enterprises and punch bad guys. Similar to Batman, it’s very expensive to be Ironman — around $354,706,000 based on this incredible infographic and some of my own assumptions. If Tony Stark used this money to pay for carbon offsets, he could offset 1,352,016 average Americans, or just about the entire population of Manhattan.