Solid fuel

Solid fuel is a burnable item used as an alternative fuel source and as an intermediate in some production chains. It is produced in a Chemical plant and can be made from heavy oil, light oil or Petroleum gas; on some maps a unique ammonia-based recipe is available. Solid fuel can also be obtained from recycling scrap, which can be mined on Planet discovery Fulgora.

Light oil gives the best direct oil-to-solid-fuel conversion, with a 10:1 input-to-output ratio. Heavy oil can be cracked to light oil first; that changes heavy oil’s effective conversion from 20:1 to 13:1 when processed optimally. On the Aquilo map the ammonia recipe is significantly more efficient: converting the products of advanced oil processing to solid fuel requires about 10.55 crude oil per solid fuel, whereas producing solid fuel from ammonia requires about 6 crude oil per solid fuel. All standard liquid-to-solid-fuel recipes are performed in a Chemical plant; the ammonia route requires both a Chemical plant and a Cryogenic plant.

• Recipes: Solid fuel from Light oil; Solid fuel from Heavy oil (or Heavy oil → Light oil → Solid fuel when cracking); Solid fuel from Petroleum gas; Solid fuel from Crude oil + Ammonia (requires Cryogenic plant).
• Production facility: Chemical plant (ammonia route additionally uses Cryogenic plant).
• Alternate source: recycling scrap mined on Planet discovery Fulgora.

Practical notes: each solid fuel item has a higher energy density than coal (more than three times the heat per item), but producing solid fuel requires oil refining infrastructure such as oil refineries, cracking setups and Chemical plants. If coal is abundant on a map while oil is scarce, using solid fuel as a primary power source is typically inefficient because coal is cheap to mine with a single electric mining drill, whereas solid fuel production depends on a chain of refinery and chemical production buildings. Balance the higher energy density of solid fuel against the additional infrastructure and resource demands before committing to large-scale solid fuel consumption.