Coal is the fuel that keeps a Viking base running. Smelters and blast furnaces won’t touch an ore without it, the Forge costs it to build, and a handful of recipes burn through it fast. The Charcoal Kiln is the structure that turns raw wood into that fuel, and once it’s up, coal stops being a bottleneck entirely.
Quick answer: Build a Charcoal Kiln with 20 Stone and 5 Surtling core near a Workbench, place it on bare ground or stone, then press E on it and add up to 25 Wood. Each piece becomes 1 Coal roughly every 16 seconds, and the kiln spits the finished coal out onto the ground beside it.
Charcoal Kiln requirements: 20 Stone and 5 Surtling core
The recipe stays locked until you pick up your first Surtling core. Those come from the burial chambers scattered across the Black Forest, where they sit in the fire-lit rooms guarded by Skeletons, and they also turn up in the Swamp. Five of them is the real cost here, since Stone is trivial to gather with a pickaxe or from loose rocks.
| Detail | Value |
|---|---|
| Materials | Stone x20, Surtling core x5 |
| Unlocks after | Picking up a Surtling core |
| Crafting station | Workbench in range |
| Footprint | Roughly 4×4 |
| Durability | 1,500, not damaged by rain |
| Capacity | 25 wood at a time |
| Output | 1 Coal per wood, one every 16 seconds |
Two placement rules trip people up. The kiln has to sit inside a Workbench’s build radius, and it can only go on terrain or stone structures. It will refuse to snap onto a wooden floor. If you want it under a roof, raise the ground with a Hoe until the terrain sits level with your wooden flooring and place it on the dirt instead.
Note: an active kiln gives off light and the Fire effect within about two meters on every side, which keeps you warm and scares off the creatures that fear flames.
How to build the kiln and load it with wood
A full load of 25 wood takes a little over six and a half minutes of real time. You don’t have to stand there for it. Sleeping through the night speeds the kiln along the same way it does other processing structures, so loading up before bed is the efficient play.
Which wood types the kiln accepts
Wood, Finewood and Corewood all convert at the same one-to-one rate, and the game pulls from your inventory in a fixed order when you load the kiln: regular Wood first, then Finewood, then Corewood. That matters because Finewood and Corewood are far more valuable for building and crafting than plain Wood is.
Tip: keep a chest of plain Wood next to your kilns and pull from that. If your pack is empty of regular Wood, the kiln will happily eat your Finewood stock instead.
Stop finished coal from rolling away
The kiln ejects each lump of coal onto the ground rather than holding it in an output slot. On uneven terrain those lumps scatter downhill and end up under fences, inside walls or halfway across your base. Two fixes handle it.
The simplest is flattening the ground. Equip a Hoe, select Level Ground and smooth the area around the kiln’s exit so nothing has a slope to roll down.
The second is building a low barrier. Decorative Boulders placed with the Hammer around the exit form a lip that catches the coal and holds it in one collectible pile. Some players go the other direction and dig a shallow channel so everything slides into a single pickup spot.
Other ways to get coal in Valheim
The kiln is the reliable option, but coal shows up elsewhere, and a couple of those methods are worth knowing before you have five Surtling cores to spare.
| Source | What you get |
|---|---|
| Surtlings | 4, 8 or 16 Coal depending on level, guaranteed on death. They spawn at fire geysers in the Swamp and across the Ashlands |
| Cooking station | Deliberately burn any meat and it drops Coal. Works early on but wastes food |
| Random chests | Small amounts turn up while looting |
| Ashlands wood stacks | Place a Wood stack and set it alight with a Campfire or Staff of Embers for 50 Coal per pile |
| Obliterator | Converts items into Coal, including bait bought from Haldor at a rate of 5 Coins to 1 Coal |
Coal stacks to 50 and passes through portals, so an Ashlands or Swamp farm can feed a base on the other side of the map without a boat trip.
What coal is used for
Most of your coal disappears into smelting. The Smelter and Blast Furnace both burn it as fuel, and the practical ratio works out to roughly 2.1 Coal for every bar of metal you pull out, so plan on running a surplus rather than matching ore to coal one for one.
| Recipe | Coal cost |
|---|---|
| Copper (Smelter) | 2.5 per Copper ore |
| Tin, Iron, Silver (Smelter) | 2 per ore or scrap |
| Black Metal (Blast Furnace) | 2 per Black metal scrap |
| Forge | 4 |
| Sign | 1 |
| Standing or Hanging Brazier | 2, plus coal as refuel |
| Black banner | 4 |
| Mead base: Poison resistance | 10 |
| Coal pile | 50 |
Coal also goes into the Cape of Odin, Hood of Odin and Pointy hat, and Flametal smelting later in the game.
One last thing worth knowing early: tearing a kiln down with a Hammer returns every Stone and Surtling core you spent. If you’re short on cores, you can cycle between a Smelter and a Charcoal Kiln, rebuilding whichever one you need at the time. Once cores are plentiful, though, a row of three or four kilns feeding a levelled collection pit will out-produce anything you can carry back from the Swamp.
