Hi everyone, while playing the game I’m finding plenty of higher metals I want to smelt and process, but it turns out more fuel is always needed for smelting metals and converting into spark for processing.
I wasn’t entirely satisfied with the existing thread about spark values for fuels and I wanted to answer for myself two questions:
- Are some fuels more efficient to use in the furnace than in Spark cores?
- Which coal type should I hunt for when I urgently need spark?
It was time for science, of which you can see the results below:
Spark Value Time (s) Spark/s Spark per coal Bonus for compacting Furnace Cycles Cycles/coal Bonus for compacting Spark / Cycle Peaty Soil 20 7,5 2,6667 0,125 160 Wood Trunk/Timber 30 7,5 4 0,2 150 Soft Coal 100 10 10 0,55 181,8182 Medium Coal 250 15 16,6667 1,3333 187,5 Hard Coal 800 30 26,6667 4 200 Compact Peat 300 60 5 41,6667 108.33% 2 0,2777 122,22% 150 Compact Soft Coal 1200 120 10 166,6667 66,67% 6,6666666667 0,9259 68,35% 180 Compact Coal 3000 180 16,6667 416,6667 66,67% 16,6666666667 2,3148 73,61% 180 Compact Hard Coal 9600 360 26,6667 1333,3333 66,67% 52,6666666667 7,3148 82,87% 182,2785
From this table, question 1 is answered: Compact Peat is the most efficient fuel to use for smelting, followed by the potentially more practical Compact Soft Coal or Compact Coal. Compact Hard coal is very slightly less efficient, better spent in a spark core. Peaty Soil and Wood are also surprisingly efficient, best used in a furnace if you have excess. (mass convert to compact peat and timber first) But given the huge amounts needed to smelt things you shouldn’t harvest peaty soil or wood over coal.
For question 2 I still don’t have a clear answer since this strongly depends on the abundance of coal veins, average vein yield and time taken to find them.
But I can give some recommendations:
Never skip a Hard Coal vein if you come across one when caving. Each block mined is worth 8 soft coal pieces.
Can be found reliably near lava level anywhere on the planet. Probably not a very good time investment if you don’t also need gold/silver/titanium because of the small vein sizes and difficulty navigating around lava lakes.
Worth picking up while searching for other ores if you’re not in a hurry or low on fuel. Each block is worth 2.5 soft coal pieces.
Medium coal strikes a good balance in harvesting efficiency and block value. It’s not worth as much as hard coal but the larger vein sizes make up for it and it is less dangerous to gather. They’re concentrated in certain resource rich areas of a planet (which also tend to have iron and copper) whereas most of the caves don’t have any, so it’s difficult to hunt for specifically in the caves.
If you’re low on fuel and can’t find enough medium or hard coal to keep up your fuel supply while searching for the other ores you need, this is the best remaining option. It doesn’t give much spark per block mined but it’s plentiful and scattered everywhere across all planets.
If you also need copper/iron, digging out a soft coal vein in an area where you see copper or iron can lead to more ores and give you a bit more value for your time.
If you need a lot of fuel and don’t want anything else, this is probably what you should harvest despite the higher value of the medium and hard coals.
Special mention: Compact Peat
The most efficient furnace fuel if you have it. Each block of compact peat is worth 1.8 soft coal pieces in a spark core, or roughly 2.16 soft coal pieces in a furnace. Mass harvesting peaty soil to turn into Compact Peat is very slow compared to coal harvesting though.
But there are shrines made of metamorphic rock and gleam lanterns that can be found on Munteen (and perhaps other ring worlds) which have 26 compact peat blocks under them. There are usually several in the same area. Digging these up is worthwhile if you know their locations or stumble across them, but if you don’t know of any nearby or they’ve already been looted you’re best off harvesting coal instead.
I hope you found my guide useful and happy coal mining!