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I'm trying to understand the production numbers, but it doesn't add up.

I'm starting from the beginning, so the iron production.
The thread Calculating production is asking a similar question, but there's no clear answer.

In my scenario, I have 7 electric miners and a cumulated smelting speed of 14 (4 steel furnaces + 6 stone furnaces).

The first issue is that the production screen doesn't seem to be consistent.
Over the last 10 minutes, the consumption of iron ore and production of iron plates is perfectly flat. The numbers for 10 minutes are 228 / min, for 1 minute 250 / min, for 5 seconds it oscillates between 300 and 350 per minute.

The second thing is the production speed from an electric miner. What is the meaning of the 'mining power' = 3? This with the mining speed 0.5 doesn't combine into something meaningful.
However, if I assume that 228 ores / min is correct, then I get 3.8 ores / sec, divided by 7 miners it's 0.54 (ore / sec / miner), which seems in line with the mining speed of 0.5. If that's correct, then one miner outputs one ore every 2 seconds.

Now the iron ore smelting process is 3.5 (I assume seconds), so I have a smelting capacity of 14 / 3.5 sec / plate = 4 plates / sec, which is also the ore consumption capacity.
It would make sense, since 4 is a bit over 3.8, and I can indeed see that the last miners on the belt do not work at full capacity.
If that's correct, it means that the capacity of a single steel furnace is 2 (speed) / 3.5 sec = 0.57 plate / sec.

And the theoretical ratio electric miner / steel furnace would be .5 / (2 / 3.5) = 7 / 8; dimension-wise that's miner output / furnace output = 7/8, or 7 furnaces = 8 miners.

It makes sense in the end, so unless I overlooked something, it seems to me that the 5s tab in the production screen is not correct, and the 1 min and 10 min screens are off by more than what would be the rounding error.

The 5s tab in the production screen is indeed buggy and not displaying correct numbers. I don't know what's the problem but the numbers are always too high.

As for the production numbers. For assmblers/furnaces it's quite transparent:

Every item has a base production time and every assembler has a base speed. To calculate the seconds per item you just divide the base production time with the base speed or for items per second you do the opposite.
So for iron plates the base production time is 3.5 and the base speed of stone furnaces is 1 meaning 3.5 s production time per item or 0.2857 itmes/s. If you use steel or electric furnaces the production time is halved since both furnaces have a base speed of 2. 3.5/2 = 1.75 seconds /item (and 0.5333 items/s which is very close to your calculation of 0.54).

For miners it's complicated and not clear. First of all mining power is not relevant at the moment (maybe it was in prior versions). Every mineable ressource has a mining hardness (which is comparable to the base production time) and iirc it's 0.9 for all mineable materials (iron/copper/stone/coal). The electric miner has a base speed of 0.5. This gives 0.9/0.5 = 1.85 s/item or 0.555 items/s.

You can change this with the use of modules. These act as a mutiplier to the base speed of the assember/furnace but don't change the base production time (can't be changed afaik).

For a perfect ratio you need about 6% more miners than furnaces (given you use the faster steel or electric furnaces with a base production time of 2). Why there is this discrepancy I don't know and in fact think it should be removed. But at least that's how it's calculated at the moment.

Ah yes, it works better when taking the hardness of 0.9 into account!

In this case, we get
- miner output = .5 / .9 ore/s = .55 ore/s
- smelter output = 2 / 3.5 plate/s = .57 plate/s

With my 7 miners and 7 steel furnaces, I get consumption = 7 * .55 = 3.9 ore/s = 233 ore/min, which is in between the 10 min production tab (228/min) and the 1 min production tab (250/min).
I guess that could be some rounding error.

Thanks for the clarification!


By the way, it almost looks like the devs are making it complicated on purpose

tralala wrote: For miners it's complicated and not clear. First of all mining power is not relevant at the moment (maybe it was in prior versions). Every mineable ressource has a mining hardness (which is comparable to the base production time) and iirc it's 0.9 for all mineable materials (iron/copper/stone/coal). The electric miner has a base speed of 0.5. This gives 0.9/0.5 = 1.85 s/item or 0.555 items/s.

I'm afraid this is completely incorrect. The mining rate is not speed / hardness. Rather it is:

Speed * (Power - Hardness) / Mining time.

An electric drill has a power of 3 and speed of 0.5. Stone has hardness 0.4 and iron 0.9, both have mining time of 2.

So this gives:

Stone: 0.5 * (3-0.4) / 2 = 0.65 / s
Iron: 0.5 * (3-0.9) / 2 = 0.525 / s

If power is high hardness doesn't matter too much. But if your power is, say, 1, iron will be 6 times harder to mine than stone. Power is like damage per hit, speed is hits per second, hardness is armor, time is health.

If you mod the power to be below the hardness, you'll get a negative mining rate I checked.

Holy-Fire wrote:

tralala wrote: For miners it's complicated and not clear. First of all mining power is not relevant at the moment (maybe it was in prior versions). Every mineable ressource has a mining hardness (which is comparable to the base production time) and iirc it's 0.9 for all mineable materials (iron/copper/stone/coal). The electric miner has a base speed of 0.5. This gives 0.9/0.5 = 1.85 s/item or 0.555 items/s.

I'm afraid this is completely incorrect. The mining rate is not speed / hardness. Rather it is:

Speed * (Power - Hardness) / Mining time.

An electric drill has a power of 3 and speed of 0.5. Stone has hardness 0.4 and iron 0.9, both have mining time of 2.

So this gives:

Stone: 0.5 * (3-0.4) / 2 = 0.65 / s
Iron: 0.5 * (3-0.9) / 2 = 0.525 / s

If power is high hardness doesn't matter too much. But if your power is, say, 1, iron will be 6 times harder to mine than stone. Power is like damage per hit, speed is hits per second, hardness is armor, time is health.

If you mod the power to be below the hardness, you'll get a negative mining rate I checked.

Thanks Holy-Fire, you are correct. I checked after I had written my post and although stone is mined faster than ore it was nowhere near my formula. So now we now for sure!

I wonder what the reason is to introduce hardness. It doesn't seem to play a major role in the game. As of now it's seems to me be one of those features which add conmplexity but not depth. Maybe it's more relevant for some mods.

tralala wrote:

Holy-Fire wrote:

tralala wrote: ...

Thanks Holy-Fire, you are correct. I checked after I had written my post and although stone is mined faster than ore it was nowhere near my formula. So now we now for sure!

I wonder what the reason is to introduce hardness. It doesn't seem to play a major role in the game. As of now it's seems to me be one of those features which add conmplexity but not depth. Maybe it's more relevant for some mods.

You are right, currently it doesn't matter a lot because the mining powers are too similar. I still think it adds depth, at least at the idea level. And it would be easy to make it more meaningful - e.g., hardness of copper could be increased, so that you're barely able to scrape copper with burner drills, and have to move on to electric as soon as possible. There could also be more advanced resources with high hardness so that you'll need new, more powerful drills to mine effectively.