While most authors (especially of the semi-scifi variety) don’t know how to do the research. I like to imagine I’m an exception to the rule. I sit down and do research after research after research into everything I work with. This is why I like to stick to vagueries (it’s a real word, honest) and things which don’t require math because they’re imaginary concepts which don’t HAVE to obey the laws of physics. “It’s magic, I ain’t gotta explain shit” is my favorite phrase ever.
Anywho, this is an introduction to the math I did. Apologies for sloppy record keeping- with exception to stuff in parenthesis, this is a collection of research reference notes for whenever her abilities are shown… not a finalized product intended to be shown to the reading public. I was just writing this shit down so I could !SCIENCE!
Kcals required by human bodies per day= 2,000-4,000… 83.3 to 166.6 per hour… Cass no sleep (we burn less energy while sleeping)… ~3600 base= 150kcals/hr= 1 Cass (Yes- I did, indeed, *invent a new measurement* to make future calculations easier) (Can up to double all her attributes, at the cost of doubling the energy costs for that period of time, plus climbing energy lost the longer she overclocks due to exhaustion)
1 calorie= heat a gram of water by 1 celsius.
1 kcal= heat a kilogram by 1 celsius
1 kcal= 4184joules (watts= j/s… a 100 watt bulb is burning 2065 kilocals per “day”)
1 calorie= 4.184 joules
1 kj= 0.239 kcals
MJ= Megajoule= 1,000,000 joules
MJ= 239 kilocals= 1.6 Cass (see- new measurement doin’ work- Cassie can get 1.6 hours out of a single megajoule worth of heat energy. Pity she can’t draw on electricity in its pure state.)
LPG= Propane/Butane= 46.4MJ/Kilogram (Thankfully, OTHER people did research for me)
https://en.wikipedia.org/wiki/Energy_density)
Propane= 46.4MJ= 11,089 kilocals per kg of propane= ~74 Cass/Kg
1 gal propane= 1.87 kilograms= 1.87*46.4mj*1.6Cass= 138.8 hours (Which is to say “an awful lot” for something which costs around 2 dollars per gallon right now- price subject to changing randomly for no apparent reason- I wish I could survive for over five and a half days on two bucks- that would be awesome)
(Random factoid- that same number is also 20737.552 kilocals)
(rough) Human Body Energy calcs
Base temp= 37 celsius
~ 80kg of water to 100kg of mass (round up to account for other materials- because 100kg is mah favorite scale-default)
1 human body degree= 80 kcal (approximate and with someone weighing around 100kg/220 pounds)
37 degrees= 2960 kcals (to bring a human to freezing water)= 19.7 Cass
(Frozen) Carbon Dioxide = -78.5c. = 9280 kilocalories= 61.8 Cass. (Or… less than half the energy in a gallon of propane, but 2 and a half days of her base state)
-273.15c (Absolute Zero)= 74,125.85 kcals. (Or… something like 3 and a half gallons of propane. And, no, Cassie *cannot* drain someone down to Absolute Zero. She doesn’t even come close. Her limit is solidifying carbon dioxide. Given Price’s powers locking on to human psycho-symbolism, and the fact that carbon dioxide is a *human waste product*, that should give you some indication of how fucked in the head Cassie is, and how cruel powers- and, by extension, I- get.)
(End of maths- back to me rambling).
It was somewhere around this point I realized, not for the first time, how *insignificant* humans are compared to the tools we so casually wield and the sheer scale of the shit we fuck with. We play with powers that are, if not beyond our comprehension, then certainly beyond our appreciation. The energy involved in these things is crazy once you start using words like “1 human worth of power” and realize that almost anything important in our lives is doing twenty or thirty times that without so much as a thought. Seriously… we eat the same amount of power as a damn lightbulb… that’s just sad…
Also a good point to remind people that electricity is fucking dangerous and will kill you if you use it wrong. So, for that matter, will propane. And just about anything which uses electricity and/or propane.
And I recall a certain little song that, while the science is a bit sloppy (and a lot outdated), the point remains true today as it has ever been.
We 90s kids had the best childhoods. Full stop. Ankle-biters today get handheld computers before they’re 10 years old. In the future, they’ll just have knowledge downloaded straight into their brain-chips. But we… we had Animaniacs, and there’s nothing you can do which will top that.
Anyhow… I have come to the conclusion that being a thermovore means there will be absolutely no shortage of energy sources Cassie can use to keep herself topped off. And that’s boring, so I’mma default back to “it’s magic, not explaining shit.” Except! I have an explanation!
Efficiency!
Power taken from other sources tends to be wasted. It still works, mind, but her power is inherently vampiric and harvests a larger percentage kcals from living sources (or Com’s projections) for several reasons. Not the least of which is simple shielding- her power has to protect her from the heat of setting herself on fire, or the cold of being covered in significantly subzero environs.
Fun fact- there are some places on Earth that get cold enough that Carbon Dioxide can solidify. Not many, but they exist.
So. Yeah. I now have a “scientific” reason why nomming people works better than other sources, though said other sources can still be used.
And you fine folks get something of a bonus chapter, since the hours I spent doing all the above research and math ate into chapter writing time. Because I love you folks, and I want all of you to know the processes that go into writing Price.
Price 
If we’re counting chemical energy, a living human has all sorts of energetic compounds (which we are able to use, including to heat ourselves up), such as fat, proteins, sugars, and the occasional ethanol. If Cass doesn’t actually absorb that, then at most she can get the fire’s current energy – which is likely only a fraction of the fuel’s potential power.
I believe you may have overestimated Cass”s normal energy needs – most people (excepting professional athletes) need way less than 3600 kcal a day:
http://www.nhs.uk/chq/Pages/how-many-calories-do-teenagers-need.aspx?CategoryID=62
I guess what I mean to say is: that’s some impressive dedication and thought you put into this. May I try to help?
Also, I shudder to think of what Cass could do (if she absorbs potential energy) should she just go storm chasing for a bit. Lightning is *very* energetic.
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She only draws on the heat energy, no other options. She no longer has a digestive tract, and can’t draw straight from the power outlets.
Well, technically, some amount of electricity would convert to heat, which would feed her… but her body’s about as conductive as ice. Which is to say “not very”.
And, yeah, Cassie uses more power than most, that’s intentional. Her body consumes a lot of power in exchange for such advantages as “does not die in freezing rivers”, “does not need air” and “getting shot in the face isn’t a serious inconvenience”.
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I meant – if she consumes a propane fire, does she consume all of its potential energy? Or does she just put the current fire out, and needs to set a given amount of propane on fire multiple times to consume it?
Or, does she only consume the heat that gets specifically irradiated and conducted to her (in which case her best bet is to lay atop the fire, rotisserie style)?
If she can absorb all the potential heat energy in a propane fire, shouldn’t she be able to do the same to humans? If she can’t, then burning stuff for energy would be horribly inefficient, since she’d waste a bunch of the energy setting it on fire repeatedly.
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No. No draining potential energy in a direct fashion, and she doesn’t put fires out. Well, she *can* if she puts effort into it by reducing the temperature of the object to the point where it won’t react (or just smothers the flame)- but that greatly depends upon what’s burning.
Ultimately her power’s primarily conductive in nature (plus some for vampirism). Vastly accelerated compared to natural conduction, but still conduction. If she were to stick her hand in propane, she’d get the ambient heat from the propane, but it would remain chemically propane (very cold propane) until lit on fire.
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OK. So she gets energy from a fire, but not all its energy (some is required to maintain the reaction).
Hm… she could theoretically also just immerse herself in the ocean. I’m assuming she’d absorb the heat from the surrounding water, but that would probably disperse rather quickly – and since salt water freezes at low temperatures, she could get a lot without encasing herself in ice.
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