So I have given this some more thought... and my initial conclusion is... yeah the extra solid fuel given by the productivity modules outweigh the efficiency modules to a slight degree.BlakeMW wrote:I'm also a fan of solid fuel. But technically I think productivity modules give a much greater benefit than efficiency modules, I'm sure someone has calculated this somewhere already, but I couldn't find it.MeduSalem wrote:Solid Fuel+Steam it is for me.
All of the items above have Efficiency Module 2's inside them to decrease the energy overhead during the refining processes.
I'll just take a hypothetical setup of 3 solid fuel plants
Normally these will produce a solid fuel in 2.4s, the chemical plant consumes 210kW so the total is 504kJ or 100kJ with eff2 modules.
For 3 chemical plants with eff2 modules:
3 light oil -> 3 Solid Fuel = 75MJ - 0.3MJ = 74.7MJ
Now we use 2x prod3 modules in the chemical plants and add a single 2x speed3 beacon:
The chemical plant has a crafting speed of +20% so crafts in 2s, it consume 693kW so the total is 1.4MJ
The beacon uses 480kW so consumes 0.96MJ, this is shared between the 3 chemical plants.
3 light oil -> 3.6 Solid Fuel = 90MJ - (4.2MJ + 0.96MJ) = 84.84MJ
That is a 13% increase in net energy yield for using prod3 and speed3 modules instead of efficiency modules.
(The astute reader will notice however, that I've so far neglected the fact that Boiler efficiency is only 50%, so if the electricity is coming entirely from steam power we actually need to divide the fuel value by 2 but keep the machine consumption values the same, in this case we get 36.9MJ net profit for eff2 modules and 39.84MJ net profit for prod3 modules: only a 9% increase instead of the 13% increase if we assume electricity comes from Solar).
1 speed beacon to 3 chemical plants is not a great configuration, you'd probably be using something like 8 beacons to 6 chemical plants with the beacons also benefiting refineries or other things, in this case the chemical plant has a speed of +370%, with a crafting speed of 5.875 it crafts a solid fuel in only 0.51s and even with an energy use of 1.7MW only consumes 0.73MJ per solid fuel crafted due to the productivity bonus and very short crafting time, and while the beacons are also consuming a fair bit of power it is shared over many machines and comes out to only a small amount per item crafted (perhaps 0.3MJ).
So I think with optimal usage of prod3 modules in refinery and chemical plants you can get almost 40% more net energy than with efficiency modules, or perhaps 30% if you're running purely on solid-fuel based steam power. Efficiency modules are still great to use in other machines if you want to improve your energy balance, but the argument in favor of productivity modules in oil refining line is very compelling.
BUT and that's the killing factor for me... the beacons and productivity modules increase the energy consumption overhead so distinctively that you have to build even more Boilers+Steam Engines to power the productivity Modules from the Solid Fuel plant if you don't want to lose on net gain. And that's where I simply give up on further experiments/calculations because I don't really know how to calculate that kind of complex efficiency crap in a simple manner.
What there should be in the end is "how many Chem Plants with Productivity Modules do I need in comparison to Chem Plants without Productivity Modules or in comparison to Chem Plants with Efficiency Modules"
And that's what I can't get to work even after trying to fiddle in Excel for 4 hours. What a waste of my time.