Calculating Energy Output from engines

[Lishget]

I can't find information for this thema... The steam engine produces maximal 673 kW. But from where comes this number? In the entities.lua is no output specified.

[DaveMcW]

{
type = "generator",
name = "steam-engine",
fluid_usage_per_tick = 0.1,
}

{
type = "fluid",
name = "water",
default_temperature = 15,
max_temperature = 100,
heat_capacity = "1KJ",
}

0.1 water/tick * (100 degrees - 15 degrees) * 1 kJ/degree = 8.5 kJ/tick
8.5 kJ/tick * 60 tick/s = 510 kJ/s = 510 kW

[Lishget]

Thanks