I am currently creating my own custom sci-fi tabletop RPG system. While I'm willing to make concessions where necessary, my goal is to use plausible physics whenever possible, at least when it comes to units of measurement.
At the moment I am creating a system to track energy usage for various equipment, such as hand-held tools, suits, and laser weapons. Most equipment is charged by power cells, which will function similarly to ammo in a video game sense. For example, a laser rifle might be able to fire 10 blasts before its power cell needs to be reloaded. A small handheld scanner, on the other hand, could run for 5 hours before requiring a new power cell.
Power cells will come in 4 sizes.
- Small (hand-held scanners, flashlights, computer tablets, laser pistols, etc.)
- Medium (power tools, laser rifles, remote operated drones, etc.)
- Large (laser cutters, spacesuits, floodlights, etc.)
- Huge (power armor, mounted laser turrets, etc.)
Obviously, I'm aware that some elements of my setting aren't completely realistic (e.g., laser rifles) but I would like to track the capacity of each power cell size with a real world unit such as watt-hours.
What units of measurement would make the most sense for each power cell size?