It would be nice if using your mod was more realistic because it would make it more efficient to use your mod then when possible.
Because the standard boiler to steam to electric conversion is unchanged, this conversion is 100% so it is completely OP.
Realistically steam generators operate around 40% efficiency because you are converting heat to another medium, electricity.
Converting steam heat to another type of heat is more close to 100% than going to electric first, it's around 85-95%.
And because the standard steam generator is at 100%, and the electric heater that you have is also very close to 100% efficient, it becomes a nobrainer to use instead of all other options and is OP. Converting electric to heat in a resistive element is actually very close to 100% and very efficient so that is realistic.
So basicly:
Standard boiler ~ 70% efficiency.
Standard steam engine ~ 40% efficiency.
Steam heater (steam to heat) ~90% efficiency.
Oil to heat ~80% efficiency.
(your stuff are already pretty realistic, your oil burner is 90% but it's the vanilla system that is broken)
Because the standard boiler is the one outputting 100% efficiency, this should be nerfed to around 70%. So then in a vanilla steam setup you would burn coal or something at 70% efficiency to convert it to heat (to generate steam inside the boiler) and then take that output and generate electricity at 40% efficiency.
So: Vanilla boiler would consume 1.8 MW of coal, generate "1.26 MW of steam". That would be around 42 steam per second instead of 60, and the vanilla steam generator should then consume half that and generate 40% of the power, so it would consume 21 steam per second and generate 252 kW of power. Why changing the steam output of it is so that if you use coal in a boiler to generate steam, it would be more balanced to other stuff (mods) that use steam and this 70% conversion is baked into it so that your heat stuff becomes more usable in those cases aswell.
So....with this remodification of the vanilla steam engine and combined with your stuff, using your mod and thermal solar and other would make much more sense, and would encourage people to tinker around with it much more. Otherwise doing vanilla steam power and then just an electric heater is always going to be the most efficient option.
Now with this change, you could even use oil to turn into heat, to then turn heat into electricity, as it would be around 20% more efficient than burning coal in a normal boiler and then generate electricity.
