Arc furnace VS blast furnace

[Nimsy_Van_Hinden]

Good day, dear development team!

Today I was wondering how much better an arc furnace is compared to a blast furnace. I noticed that a blast furnace, using one piece of coal as fuel, can perform 28.33 smelting operations. Meanwhile, the arc furnace only manages 13.88 smelting operations.

A regular furnace achieves 14.77 smelting operations.
This makes the arc furnace the least efficient burner when it comes to fuel efficiency.

Is this intentional?

Additionally, the arc furnace consumes 6 kW when idle, which makes it even worse in terms of energy efficiency.
On top of that, the arc furnace requires a 3x3 build space, while the other two furnaces only need 2x2. Moreover, additional space in the factory is required to generate electricity, which is not the case for the other two furnaces.

One advantage of the arc furnace is the ability to insert modules, which can be beneficial when pollution is a concern.
Another advantage is that arc furnaces can be built in space.
But that’s where the advantages seem to end.

Did I overlook something when thinking this through, or is the arc furnace simply worse than the blast furnace?

Best regards!

P.S.: I absolutely love this game!!! <3 (and you guys too <3)

[Nemoricus]

What mod are you using?

[Nimsy_Van_Hinden]

It’s just the normal Space Age mod

[Nemoricus]

There is nothing called arc furnace or blast furnace in Space Age.

There are the stone, steel, and electric furnaces. The first two are 2x2 and the electric is 3x3.

Then there is the foundry, which is not a furnace and does not run furnace recipes. It is 7x7.

[Tertius]

Could you please use the original English game terminology? Please don't translate your localized game terminology back to English, instead use what the game uses if you switch it to English. Often, this is different. Otherwise it's not clear what you're talking about, since we probably don't know your native language.

[Nosferatu]

If this is not a mod thing then maybe a translation problem?
The 3 furnaces are Stone, Steel and Electric
Check the link below to check their stats.
https://wiki.factorio.com/Electric_furnace

Are you talking about these?

[Nimsy_Van_Hinden]

Sorry, I’m playing in German.
The correct abbreviations are, of course, Stone, Steel, and Electric.

Perhaps the following image illustrates my thoughts better

[atomizer]

Correct, under these specific conditions (using only burner fuel, no modules) electric furnace is worse. However it is superior when using other sources of electricity (solar, nuclear). Modules and beacons also make the decision clear later in the game.

[adam_bise]

Keep in mind coal is not the only way to power an electric furnace. You can also use solar panels which is free. Nuclear power once set up is highly efficient and would power much more than your furnaces. The existence of module slots in the electric furnace alone makes it superior because of prod modules, and also allows the use of beacons. Foundries are even better.

[Nimsy_Van_Hinden]

Oh, you’re right!
I completely forgot about nuclear power…
Thanks for reminding me.

[kpreid]

Even ignoring the power of Productivity Modules, if you put two Efficiency Module 1 or Efficiency Module 2 in an electric furnace, then it consumes less power and produces less pollution than a steel furnace. So, it seems like it should make sense to switch to electric furnaces as soon as you have them available, provided that you use any modules at all with them to get some advantage, whether it is efficiency, speed, or productivity.

[Tertius]

The furnaces scale. Usually, you want to produce more and more as you proceed through the game. The stone furnace is the start. It produces some given amount. The steel furnace doubles the speed, so it doubles the output. That's direct scaling.

The advantage of the electric furnace is more scaling. Not as direct as in the lesser furnaces. It's the same base speed, but you can use beacons and modules to increase output with the same footprint. Only the electric furnace can be boosted that way. It comes with a cost, and this cost is energy.

But if you proceed through the game, you will notice energy becomes cheaper and easier to produce. So the furnace itself is less efficient in terms of energy, but the whole system of power production (in a power plant) and power consumption (in the furnace+beacon+module) is more efficient, if you calculate the energy required per plate in the output. You will usually use production modules as well, so you need less input, which lessens the drain on your resource patches, and the energy required to actually mine.

You have the choice to create vast fields of steel furnaces that eat vast amounts of coal, or to create a much smaller field of electric furnaces and a small nuclear power plant (nuclear power is essentially infinite energy, you will never run out of uranium ore). Small nuclear power plant if you compare it with the footprint a corresponding steel furnace factory requires.

The final scaling is the foundry. It's even more efficient and faster than the electric furnace. What you can do with a field of 200 steel furnaces can be done with a field of 50-80 electric furnaces, and this can also be done by perhaps 8 foundries (didn't actually compute numbers, but that's roughly the ratio). All including beacons and modules. And the 8 foundries will probably consume even more energy than 80 electric furnaces. But that's ok, use nuclear power. And the foundry needs much less input due to its productivity, so you need half the mines, half the trains, for the same production output.

[Nimsy_Van_Hinden]

Great and satisfying answer! Thanks a lot.
So, I’ll stick to the steel furnaces until I have unlimited power. I don’t want to use solar panels, and I want to keep my coal consumption low.

[Tertius]

In earlier 1.1 playthroughs, I tried to go to electric furnaces very soon, but I always struggled with power supply. So I just kept steel furnaces until nuclear power. Modules are a huge energy drain anyway, no way to use them without nuclear power. Vast fields of solar power could work, but that's just tedious to create.

In 2.0, with my first playthrough, I skipped electric furnaces entirely. I just kept all the steel furnaces. They worked. Production was enough, coal supply was enough, energy usage was ok. I went to Vulcanus first, unlocked the foundry and built a Vulcanus base. At the same time I researched nuclear power, mined uranium ore, processed it and started to accumulate uranium-237 so I had enough the moment I unlocked the kovarex enrichment process. This is the key to infinitely scaled nuclear power. I built the first nuclear power plant, replaced all the steel furnaces with a few foundries, and realized I need just half the trains now. No new mines to explore for a while, so there's enough time to explore space.

[FunMaker]

Best argument IMHO that was not mentioned is that electric furnaces reduce the logistic requirements. You don't have to bring ore AND coal to the furnaces, just ore! That makes the build much easier and increases scalability by a huge margin!

[Nemoricus]

Great and satisfying answer! Thanks a lot.
So, I’ll stick to the steel furnaces until I have unlimited power. I don’t want to use solar panels, and I want to keep my coal consumption low.

Efficiency modules mean that electric furnaces consume less power and therefore less coal.

[astroshak]

Best argument IMHO that was not mentioned is that electric furnaces reduce the logistic requirements. You don't have to bring ore AND coal to the furnaces, just ore! That makes the build much easier and increases scalability by a huge margin!

Thats an important consideration for designing a new area. But for maintaining the old smelting area, it is often simpler and just as effective to maintain the smelting columns rather than redesign them for electric furnaces.

[angramania]

So, I’ll stick to the steel furnaces until I have unlimited power. I don’t want to use solar panels, and I want to keep my coal consumption low.

Even with boiler power it worth to switch to electric with modules. Electric and steel have the same smelting speed. With two level one efficiency modules electric consumes 78kW and steel 90kW, which means 1.17 coal per minute vs 1.35. Also steel always produce 4/m pollution but electric pollution drops with modules from 4.1/m ( 1/m own + 3.1/m boiler) to 1.7/m (0.4/m + 1.3/m).

[Premu]

From a physical point of view it even makes sense that it is inefficient to turn coal into electricity, and use that electricity to heat up the furnace. Only about 40% of the energy stored in the coal can be turned to electricity. While burning it directly will allow you to use most of it to do the smelting.

Thats an important consideration for designing a new area. But for maintaining the old smelting area, it is often simpler and just as effective to maintain the smelting columns rather than redesign them for electric furnaces.

I also keep the old smelting areas as long as I don't completely rebuild the base. Coal is not a limiting factor on Nauvis. It's typically either copper or iron ore. So if I have enough of the old smelters and a working coal supply, I just keep on burning it. Of course, should I switch over to a modular mega base, I exchange these with electric smelters (pre-space-age) or foundries (space age)