Caloric Engine
Burns any furnace fuel into power. Usually the first engine you build.

- Output
- 40 FE/t
- Buffer
- 20,000 FE
- Fuel
- Furnace fuel
- Upgrades
- Kits, modules
- ID
enthalpy:caloric_engine
What it does#
The Caloric Engine burns anything a furnace burns and turns it into FE. It makes 40 FE/t while it has fuel, and pushes that power out of its front into whatever is touching it.
Fuel is worth more here than in a furnace. A piece of
Coal gives
60,000 FE, enough to run the engine for
75 s,
and the engine lights the next item before the last runs out, so its output doesn't dip between items.
Building it#
Crafting Table







Using it#
Put fuel in its one slot, by hand, by hopper, or by turning on auto-input. Click the tabs and the coloured faces below; they behave like the real screen.
8
- Burns any furnace fuel for FE
- Pushes FE out of output faces
- Auto-input pulls fuel from neighbours
- Celerity: more output, more fuel per FE
- Economizer: more FE per fuel item
- 1The engine's own store of power. It fills while nothing takes the FE and empties as neighbours draw it.
- 2Running while it burns. Idle when it's out of fuel; Disabled when redstone has switched it off.
- 3The fuel slot. The flame above it lights while fuel is burning.
- 4What it makes each tick, how full the buffer is, and how long the item now burning has left.
- 5Which faces take fuel and which push power. Click a face to change it; right-click to go back.
Fuels#
Every furnace fuel works. Most are worth their furnace burn time × 25 FE × 1.5, rounded to the nearest 250 FE; a few have a set value of their own. Some common ones:
| Fuel | FE per item | Burns for, at base rate | Value from |
|---|---|---|---|
| 60,000 FE | 75 s | burn time | |
| 60,000 FE | 75 s | burn time | |
| 540,000 FE | 675 s | fixed | |
| 80,000 FE | 100 s | fixed | |
| 100,000 FE | 125 s | fixed | |
| 200,000 FE | 250 s | fixed | |
| 11,250 FE | 14.1 s | burn time | |
| 11,250 FE | 14.1 s | burn time | |
| 3,750 FE | 4.7 s | burn time | |
| 3,750 FE | 4.7 s | burn time |
Automation#
Out of the box it powers whatever its front touches, no cable needed:
Front Output (pushes FE); Every other face Input (takes fuel). Auto-input off, Auto-output on.
Feed fuel by hopper or pipe into any input face, or turn on Auto-input to pull it from a chest beside it. Side configuration explains faces, modes and redstone control for every machine.
Upgrades#
A tier kit raises its output and buffer and opens module slots.
| Tier | Kit | Output | Buffer | Module slots |
|---|---|---|---|---|
| Base | None | 40 FE/t | 20,000 FE | 0 |
| Tempered | 80 FE/t | 40,000 FE | 2 | |
| Fortified | 120 FE/t | 80,000 FE | 4 | |
| Luminous | 160 FE/t | 160,000 FE | 6 | |
| Harmonic | 240 FE/t | 320,000 FE | 8 |
Celerity Module · up to 4
Economizer Module · up to 4
Engines trade their two modules against each other:
- Celerity raises output by 50% each, but every item of fuel gives less FE.
- Economizer adds 34.375% FE per item each and 25% buffer.
Four Celerity modules triple the output, 3×, at 33% of the FE per item. Four Economizers get 2.375× the FE from every item at the same output. Four of each give 79% of the FE per item at triple the output.
Good to know#
- Its running sound is a crackle over a low hum. Turn it off with Sounds on the Configuration tab.
- With Jade installed, looking at the engine shows its output and the fuel left.
Sawdust from the Kerf Mill is fuel, so a log-sawing line can feed its own engine.
For pack makers: the settings behind these numbers
| Setting | Default | Range | What it does |
|---|---|---|---|
engines.energyPerTick | 40 | 1 to no limit | FE per tick the Caloric Engine generates while burning, before upgrades |
engines.energyCapacity | 20,000 | 1 to no limit | Energy buffer of the Caloric Engine before upgrades, in FE |
engines.maxEnergyOutput | 1,000 | 1 to no limit | Maximum FE per tick the Caloric Engine pushes out before upgrades |
engines.caloricEnergyPerBurnTick | 25 | 1 to no limit | Caloric Engine FE per tick of a fuel's furnace burn time, before caloricFuelEfficiency Items in data/enthalpy/data_maps/item/caloric_fuels.json use their fixed value instead |
engines.caloricFuelEfficiency | 1.5 | 0.01 to 100 | Multiplies the FE the Caloric Engine gets from burn time, rounded to the nearest 250 FE (1.5: coal gives 60,000 FE) |
upgrades.rateMultipliers | 1 / 2 / 3 / 4 / 6 | Energy rate (and therefore speed) multiplier per tier: base, tempered, fortified, luminous, harmonic | |
upgrades.capacityMultipliers | 1 / 2 / 4 / 8 / 16 | Energy buffer and transfer multiplier per tier: base, tempered, fortified, luminous, harmonic | |
upgrades.celeritySpeedBonus | 0.5 | 0 to 100 | Extra speed per Celerity module (0.5 = +50%) |
upgrades.engineEconomizerFuelBonus | 0.3438 | 0 to 100 | In engines, each Economizer module adds this much FE per unit of fuel (0.34375 = +34.375%), while each Celerity module divides it by (1 + celerityCostIncrease). With the defaults, 8 Celerity and 8 Economizer modules leave an engine at 75% of its base FE per fuel, and 8 Economizers alone at 375%. |
upgrades.engineEconomizerCapacityBonus | 0.25 | 0 to 100 | In engines, each Economizer module grows the energy buffer by this much (0.25 = +25%) |
Fuels with a set value are in the enthalpy:caloric_fuels data map.
Related#
- Fuel tables: every fuel for every engine
- Choosing an engine and fuel
- Voltaic Cell: store what the engine makes
- Upgrades and modules