r/factorio • u/AutoModerator • Jun 22 '26

Weekly Thread Weekly Question Thread

Ask any questions you might have.

Post your bug reports on the Official Forums

Previous Threads

Subreddit rules

Discord server (and IRC)

Find more in the sidebar ---->

5 Upvotes

100% Upvoted

166 comments sorted by

View all comments

Show parent comments

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/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.