Her carbon footprint depends a lot on how childish we want to be.
Firebird is a superhero in the Marvel Universe who can conjure fire all around her and create fire tornadoes that allow her to briefly fly. I repeat: fire tornadoes!
So Firebird needs to be burning something. Burning something, anything really, releases an impressive amount of carbon into the atmosphere. To calculate Firebird’s carbon footprint, we need to know 1) how much something she’s burning per hour, 2) how long she engulfs herself in flames, and 3) what exactly she’s burning.
Humans light things on fire. LOTS of things. Let’s look at some of those things that make really big flames.
We’ll begin with the Olympic flame. The propane industry has its own magazine, believe it or not. In it, they report the fuel consumption rate for the Olympic flame at 1,100 gallons per hour. It’s unclear to me if this is liquid propane, or gas. But we’ll go with liquid for now.
For comparison, let’s look at another big flame. When people drill for oil there’s often some flammable gas left over. Rather than try to contain those leftovers, companies will often burn it as a natural gas flare. This is actually safer than trying to bottle it up. According to the EPA, natural gas flares can consume several cubic meters to thousands of cubic meters of gas per hour. For someone who can create and control fire, like Firebird, it’s probably safe to assume that she’s on the high-end of that range. So we’ll guess she uses around 3,000 cubic meters per hour (105,944 cubic feet per hour).
And then there’s coal. A coal-fired blast furnace is a decent analog to Firebird’s abilities. According to steel makers, it takes around 550 lbs of coal to produce 2,205 lbs of metal. And according to iron workers, a furnace can turn out around 176,370,000 lbs of iron per week. Using math, we can determine that a good estimate for coal use would be approximately 262,400 lbs per hour (131.2 tons per hour), which is right around 15 dump trucks worth of coal per hour.
Now that we have burn rates, we need to know how long Firebird uses her powers. She was once a member of The Avengers, and they don’t fight all the time (sometimes they eat shawarma). Even the Fantastic Four’s Human Torch, another fire-based superhero, isn’t turning into his fiery self all of the time. Let’s be conservative and say that Firebird bursts into flames for 2-3 hours per adventure and has around 2 adventures per month. That puts her total burn time at 60 hours per year.
At last, we’ve reached the final questions: what is Firebird burning? And what is that fuel’s carbon footprint?
According to the EPA, the carbon emissions coefficients for burning various fuels are:
Propane = 12.7 lb CO2e per gallon
Natural Gas Flare = 120.7 lb CO2e per 1,000 cubic feet
Anthracite Coal = 5,685 lb CO2e per short ton
Being careful to convert all of our units, we can calculate Firebird’s carbon footprint if she’s burning like the Olympic Flame, a natural gas flare, or like a blast furnace. Those numbers come out to:
Emissions(Nat Gas Flare) = 255,749 lb CO2e
Emissions(Olympic flame) = 838,200
Emissions(coal) = 44,752,320
Here is where that whole “childish” thing enters the picture. There are flammable gases in human flatus that Firebird might take advantage of. What is flatus, you might ask?
Yeah. We’re going to take this idea seriously and make some calculations. I promise that considering flatus isn’t as ridiculous as it sounds.
Very little research has been done on human flatus. But this study is absolutely incredible. The authors document that the volume of flammable gas in the flatus released by an average person during a day is around 820 ml (50 cubic inches). The flammable part of flatus is a mix of mostly hydrogen and just a little methane, a powerful greenhouse gas.
Is it even conceivable that Firebird is using her own flatus to generate her impressive flame cloak? Well, for a two-hour adventure, she would need around 70,629 cubic feet (1,999,999,999 ml) of flatus (technically more, because the flammable part of flatus is only around 55% of the total gases). It would take Firebird 6,650 years to produce that much flatus. So, sadly, the answer is no.
The most flatus she could safely (and I use that word generously) produce in a year would be around 11 cubic feet. Her carbon footprint from flatus alone would therefore be right around 1 lb CO2e. In every possible way, Firebird just isn’t contributing to global warming via flatus. But there are animals that contribute significantly: cows. While Firebird could only produce 11 cubic feet of flatus, a cow can produce around 7,500 cubic feet of methane in a year. As of 2014, there were 9,267,000 dairy cows in the US alone.
The Final Analysis
Firebird’s carbon footprint depends on what fuel she’s burning to engulf herself in flames. It ranges from approximately 260,000-45,000,000 lb CO2e per year. Because she’s a superhero, I think it’s safe to assume that she understands how bad it is to burn coal. That means that Firebird, burning a combination of methane and propane for about 48 hours a year, likely contributes somewhere around:
Firebird = 500,000 lb CO2e
That’s around a dozen Americans’ worth of yearly carbon emissions. In short, burning stuff — no matter what it is — just isn’t particularly good for us or the planet.