# Combustible

Supplies HE as a graded fuel.

Place the object under `traits` in a fluid-property file.

## Fields

| Field | Meaning and default | Range |
| - | - | - |
| `grade` | Fuel grade: `LOW`, `MEDIUM`, `HIGH`, `AERO`, or `GAS`. | |
| `energy` | Combustion energy in HE per bucket. | `i64` |

## Example

From `data/hbm/fluid_property/balefire_fuel.json`:

```json
{
  "combustible": {
    "energy": 640000000,
    "grade": "HIGH"
  }
}
```