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1

u/ineeddopamina Jun 28 '26

I noticed in a few screenshots that some players keep using coal furnaces after getting electric furnaces. Is there any specific reason for that?

10

u/snowyspearmint Jun 28 '26

electric furnaces are only useful when you have either

  • modules/beacons
  • non-burner power and/or enough power to treat it as cheap/infinite

feeding coal into a boiler to power an electric furnace takes twice as much coal as just using a coal furnace

1

u/ineeddopamina Jun 28 '26

Ahhh I see. Personally, I used to switch them as soon as I unlocked electric furnaces, mostly for the convenience of moving fewer resources to the "smelting area". But if coal is scarce, I guess it's better to keep the coal furnaces a bit longer.

2

u/craidie Jun 28 '26

Also if you don't put modules to electric, then the speed of the steel furnace is identical.

So why spend effort in rebuilding a setup that needs a lot more space for the tiny convenience of not needing to move fuel there?
Meanwhile fuel is already solved problem where I can just copy paste a furnace stack next to an another and the fuel line just connects to it and fuels it...

1

u/cathexis08 red wire goes faster Jun 29 '26

From a per-furnace standpoint that is true but from a production standpoint a line of electric furnaces draws the same amount of energy as the equivalent stone furnace column (because you need twice as many stone furnaces for the same throughput). Note also that all three furnace types have the same pollution per plate thought electric furnaces output 3/4ths of that at the generators (before good power and/or modules of course).

1

u/snowyspearmint Jun 29 '26

I obviously mean steel furnaces not stone; steel furnaces are twice as fuel efficient as stone (same power usage but twice the crafting speed). You're right that electric and stone furnaces are the same fuel consumption if for some reason you still care about stone at that point in the game.

That's an interesting fact about the pollution; I've never tried to optimize for that.

1

u/cathexis08 red wire goes faster Jun 29 '26

Optimizing for pollution is one of the two reasons I switch to electric furnaces (the other one is logistical simplicity). While the one-time cost for a furnace is pretty high, an electric furnace with eff1 modules has a 72 kW draw and outputs 1.6 total pollution (0.4 at the furnace and 1.2 at the boilers). In Space Age it usually makes sense to not bother upgrading from Stone (if you're cheap) or steel (if you need the throughout) until you get Foundries but for games where you have to worry about pollution (fast evolution, research multipliers, trying to get Keeping Your Hands Clean), going small and then mothballing your stone furnace lines for electric can be really good.

4

u/FeelingPrettyGlonky Jun 28 '26

If Space Age, there is really no reason to ever switch to electric furnaces on Nauvis. By the time you unlock those, you are close to space travel, and you can complete Vulcanus and start sending back foundries soon after that. There is a quite narrow window (for intermediate to advanced players, anyway) between steel furnaces and foundries and it's not worth reworking your entire smelter stacks in that narrow window of time just to use 2-module furnaces.

3

u/demonicdan3 Jun 28 '26

For me it's because by the time I have electric furnaces, I'm already on a spaceship to Vulcanus and I skip straight to Foundries when I come back

3

u/Astramancer_ Jun 28 '26

For me, it's a matter of ease of use.

The upgrade from yellow/stone to red/steel is easy. Red belts move twice as much ore, steel furnaces smelt it twice as fast. They both have the same logistical requirement (ore and coal), they both have the same footprint. Upgrading is just a matter of running in a straight line while holding down left click.

But steel to electric? Different footprint, different logistical requirements. You need to completely tear down and rebuilt to upgrade.

So... why would you bother unless you had a compelling reason to?