Factorio Forums

In most of my games lately I have been using steel furnaces for all my centralized smelting needs. With steel furnaces you can make very compact setups that draw minimal power and are capable of fully compressing a belt, but you need solid fuel or coal where electric furnaces need only power.

My question is quite simple: Assuming no beacons, modules, or anything else like that, is it more fuel efficient to run steam engines and electric furnaces, or is it better to burn the fuel directly in a steel furnace?

Personally I think modules are a waste in furnaces, as production modules provide much greater return when used for circuit manufacturing and speed modules are an expensive way to just add more furnaces... Since I don't use modules the only differences that matter are efficiency and size.

Assuming you use coal for producing energy the steel furnace would be more efficient as boilers only have a 50% efficiency ratio compared to using the coal directly e.g. in a furnace.

However the big benefit of the electric furnace is the ability to use modules.
With efficiency modules you get to lower the required energy to 20% which makes them use less energy (or coal in boilers) then the steel furnace.
In the late game using productivity modules in the furnaces with speed modules in beacons is too good to pass on in my opinion
At that time most or all your energy often comes from solar farms anyways and is thus "free" (ignoring the setup cost) and thus the better option anyways.

So unless something changed in 0.15 steel furnaces are more efficient unless you use modules and/or get "free" energy from solar or other means

without modules it's much more efficient to run steel furnaces. 100 wood burning steam netted me 551 iron with an electric furnace.
100 wood in a steel furnace netted me 779 iron. without efficiency modules (lvl1) i don't bother with electric furnaces.

I'm not too enthused about production modules in furnaces, mostly because the cost/benefit ratio is MUCH better if they are used in circuits, adv circuits, processing units, and other high cost intermediate products.

Efficiency modules in electric furnaces could be very useful though...

Most of the time when tempted to use speed modules I just build a bigger factory The only case where speed modules are really useful (better than just building bigger) is depleted oil wells (and even then new oil fields are a better solution).

Well you mentioned compactness - in that case modules are the way to go tho
Since I use production modules + speed beacons in the lategame i like to setup my factory early on for that and just switch out furnaces.
I go for electric furnaces quickly and then try to get efficiency modules asap.

Also all my factory fits into roboport grid and with my setup I can fit 2 furnace arrays and the main bus that pushes all plates north in the size of two roboport grids (so in the empty spaces between 3 roboports) and have fully compressed belts

edit: also you can use production modules in the assemblers as well

milo christiansen wrote:Efficiency modules in electric furnaces could be very useful though...

The opportunity cost of those red circuits is extremely high given they could go toward higher tier prod modules in downstream products. In particular, yellow science benefits from having a lot of cumulative 40% productivity steps.

I also stick to steel furnaces until I'm at the point where I have a few thousand module 3s to spare.

iceman_1212 wrote:The opportunity cost of those red circuits is extremely high given they could go toward higher tier prod modules in downstream products. In particular, yellow science benefits from having a lot of cumulative 40% productivity steps.

Very true! I bet the saved power gained by the higher energy efficiency of steel furnaces would help offset the cost of the larger factory needed to maintain speed with lots of production modules too!

Assuming, of course, that you think solar is lazy and to be avoided (with solar, power is basically free in the long term). Since I prefer to go all steam, power consumption has a tangible cost, and hence should be kept low where possible.

I am inclined to believe that people who use lots of beacons and modules are also using massive solar farms...

EDIT: Goofed the quote, oops.

milo christiansen wrote:

iceman_1212 wrote:

milo christiansen wrote:The opportunity cost of those red circuits is extremely high given they could go toward higher tier prod modules in downstream products. In particular, yellow science benefits from having a lot of cumulative 40% productivity steps.

Very true! I bet the saved power gained by the higher energy efficiency of steel furnaces would help offset the cost of the larger factory needed to maintain speed with lots of production modules too!

Assuming, of course, that you think solar is lazy and to be avoided (with solar, power is basically free in the long term). Since I prefer to go all steam, power consumption has a tangible cost, and hence should be kept low where possible.

I am inclined to believe that people who use lots of beacons and modules are also using massive solar farms...

It's not actually too hard to feed a 1GW+ Steam setup with a few patches of Coal mines and trains, and it's not like Coal had very many other uses in 0.14 anyways (main one was Plastic bars, followed by certain military items, which were never needed in huge quantities). But yes, solar farms are nice for their 0 unit costs, of course you pay for that in fixed costs and space used. I suspect Nuclear is going to become the norm for powering megabases because of how compact it is and the nice efficiency boosting properties of the adjacency mechanics it has.

In 0.15 you are forced to make electric furnaces for production science packs so that's as good a time as any to also start using them for smelting if you haven't switched over to electric already. if you have to make thousands of them anyway, why not use them for smelting too?

milo christiansen wrote:I am inclined to believe that people who use lots of beacons and modules are also using massive solar farms...

There are some hardcore anti-solar gurus around here Just have a look at the "no-brainer solar" topic

Frightning wrote:and it's not like Coal had very many other uses in 0.14 anyways (main one was Plastic bars, followed by certain military items, which were never needed in huge quantities).

This is one reason I was really excited to see coal liquefaction, coal actually has a use (besides plastic and grenades) after you start producing solid fuel.

Kelderek wrote:In 0.15 you are forced to make electric furnaces for production science packs so that's as good a time as any to also start using them for smelting if you haven't switched over to electric already. if you have to make thousands of them anyway, why not use them for smelting too?

True enough. I'll probably start using them once my factory outgrows my current 96 furnace (2x red belt) setup, if only so I can build a separate satellite smelting base without needing to run in trains of solid fuel.

Don't forget efficiency modules cut down the pollution too. That was really helpful on biter heavy map seeds if you wanted to slow how much you anger them early on with your pollution cloud or delay that next miner expansion just a bit before some key research finished (which with RSO required usually fighting quite a few bases and that could sometimes be a problem in earlier stages especially with mods and/or trying to play without turret creep).
So i guess there is plenty of reasons to go electric early and use modules (level 1 modules are great in miners too). But in the end it comes down to how you play your game and what you like best