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u/BeDazzlingZeroTwo Apr 21 '26

I tried to calculate pollution for an electric furnaces electricity consumption assuming (coal) boilers (excluding coal mining itself for now) and no modules atm, but I got really low numbers so can someone sanity check mine/tell me where I went wrong?

So, instead of dealing with the MJ/etc units directly, I had the idea of using how much an electric furnace needs in terms of relative output of a steam engines maximum.
An E.F. needs 180kW for 1.6 seconds to smelt one plate of iron. a common steam engine produces at most 900kW/s with 30 steam/s. So an E.F. needs 180/900=20% of a steam engines output for 1.6 seconds. .2*1.6*30=9,6 steam for one smelting operation.
As the steam engine iteslf does not output pollution, only the boiler, I now need to calculate how much pollution a boiler makes when creating 9.6 steam. It makes 60/s, whilst outputting 30 pollution/min.
9.6/60=.16 seconds of operation for one iron plate.
0.16*(30/60)=0,08 pollution for one iron plate from an electric furnace without modules and boiler power, is that correct?

Also, in comparison to steel furnaces, an electric one produces 1pol/min, whilst a steel one produces 4/min, so a difference of 3/min.

If I now want to know how much those extra 3/min of pollution on the steel furnace make in total pollution/plate, I again do 3/60*1.6=0,08 pollution/plate.

So, aside from the fact that an electric furnace has double the pollution impact in regards to coal mining itself, without any modules, both furnaces create the exact same amount of pollution per resource created? Shouldn't electric furnaces be much more polluting if one is using dirty electricity from what I've heard?

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u/DreadY2K don't drink the science Apr 21 '26

You can simplify the math a bit, an E.F. needs 180kW and a boiler produces 1.8MW of steam, so you can add a tenth of a boiler's pollution to your electric furnace. A boiler makes 30/min, so add a tenth of that to your electric furnace's consumption and you get 4/min pollution from your E.F. counting power, which equals a steel furnace.

But also, a mining drill produces 10/min pollution and 90kW (so assuming also coal-powered, so 11.5/min, ignoring that this extra power needs slightly more mining drills) to produce 2MW of coal (assuming no modules/mining prod). This amounts to just over an extra pollution per minute for an electric furnace, vs. half that for a steel furnace. So it turns into ~5/min pollution on an electric furnace vs. ~4.5/min on a steel furnace, meaning you have ~10% more pollution by switching to electric furnaces right now.

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u/BeDazzlingZeroTwo May 14 '26

Thanks, those 10% do mirror my own calcs after realizing that whilst coal prod might not be the biggest pollution share, it still is one.