Coal Output

Coal Output refers to the passive hourly production rate of Coal generated by your city's Coal Mine or equivalent production buildings. Because Coal fuels the Furnace and is required for building upgrades, maximizing Coal Output is one of the highest priorities in city management.

Overview

Coal has a dual role in Whiteout Survival: it is both the fuel that keeps the Furnace running (protecting your city from deadly snowstorms) and a construction material needed for building upgrades. This means Coal Output directly impacts both city survival and development speed.

Factors Affecting Coal Output

Production Buildings

The Coal Mine (or equivalent building) provides passive Coal generation. Upgrading your Coal Mine increases both the hourly production rate and building storage capacity.

Research Bonuses

The Economy Research tree includes technologies that directly boost Coal Output:

• Coal Production — Percentage increase to base Coal generation rate
• Mining Output — General mineral output multiplier

Hero Bonuses

Some heroes provide Coal production bonuses when assigned to the Coal Mine building slot. Check individual hero skill descriptions for relevant bonuses.

Chief Gear

Development Chief Gear sets may include Coal Output increases as secondary stats.

Building Levels and Output

Building Level	Approx. Hourly Output	Notes
1	~300/hr	Starting production
5	~1,500/hr	Early game
10	~5,000/hr	Mid game
15	~15,000/hr	Late game
20	~40,000/hr	Advanced
25	~80,000+/hr	Endgame

Note: Exact values vary significantly with research and hero bonuses.

Coal Consumption

Coal is consumed by:

• **Furnace fuel** — The Furnace burns Coal continuously to generate heat
• **Building upgrades** — High-level construction requires Coal
• **Some Research** — Advanced technologies in Growth and Economy trees cost Coal
• **Gear crafting** — Some gear recipes require Coal

The Furnace is by far the largest constant drain on Coal, making it essential to maintain strong Coal Output.

Critical Warning: Furnace Coal Supply

If your Coal supply runs out, the Furnace begins to lose heat. In a snowstorm, this can result in troop casualties and city damage. Always maintain at minimum a 24-hour buffer of Coal in reserve.

Maximizing Coal Output

1. Upgrade Coal Mine buildings to the highest possible level
2. Complete Coal Production research in the Economy tree
3. Assign heroes with Coal production bonuses
4. Check building storage caps and collect regularly

Tips

• Coal Output is never "enough" at high levels: Demand always seems to outpace production — supplement with regular Coal Mining gathering.
• Multiple buildings help: Two or three Coal Mines at high levels generate far more than one maxed building.
• Always have Coal reserves: The Furnace running dry is a city-wide emergency — treat Coal like a fuel tank with a minimum level.
• Research first: Coal Production research multiplies all Coal Mine output, so invest in it early.

See Also

• Coal
• Furnace
• Resources
• Economy Research
• Coal Mining
• Wood Output
• Iron Output
• Meat Output