Hi, my name is James, and welcome to Code/Switch. Today, I want to talk about energy in Pathfinder. This isn’t just a rehash of the article I did about batteries in Starfinder, rather than capacity I’m going to talk about generation of energy. The source of energy is one every player is familiar with, the first spell players learn to love and fear, Fireball.
To determine how strong a Fireball is, or could be, we first have to make some estimates. As per the Core Rulebook a Fireball starts out the size of a pea and ends up a 20ft radius of burning hellscape. The things the spell doesn’t tell us is; how hot it gets and how long the Fireballs explosion is active. I just threw 1/2 second as the active time for the explosion, which may honestly be a little longer than it’d last, but I feel its a duration true to the spells timing of casting, shooting, and exploding in 6 seconds. As for the its temperature, at 6th level, one level after a wizard first learns to use the spell, on average it’ll do 21 damage, exceeding Fire Resistance 20 more than half the time its cast. To exceed Fire Resistance 20, you’d need heat of at least 2,187F, as per my previous article about Fire Resistance.
Now that we have our measurements we can do some math (In metric, I needed to)! Assuming an average 23c (73F), the explosion has to heat the volume of a 20ft sphere from room temperature to over 2,000F in a half a second. Using the Specific Heat Capacity of Air, its Mass, and the temperature difference between the Fireball and the ambient room, we find out how much energy we’d need to make the volume of that sphere red hot. That energy is 131,095 kilojoules.
Kilojoules doesn’t really mean much, but we can quickly convert that to kilowatt/hours, a more understandable measurement. The average US home uses 28.9 kilowatt/hours per day, our Fireball spell ends up with 72.83 kilowatts of energy, enough to power a US home for a day and a half!
Go ahead, chuck a Fireball into your steam trains boilers! It’s clean, renewable resource. Just make sure your boiler can handle rapid temperature and pressure changes, and that your wizard doesn’t get tired of your crap. If you wanna talk with me or any other member of the KD Crew, feel free to join our Discord!