Temperature
Temperature management is an important part of a productive colony. Temperature mostly affects pawn mood, food and corpse spoilage, and plant growth. In some biomes outdoor temperature can reach deadly highs, lows, or both depending on the season - pawns must wear appropriate clothing to survive long periods of time outdoors. Temperature also plays a major role and is affected by many things in world generation. Extreme cold or heat can even kill animals, and extreme heat can cause and sustain fires.
Basics
Cold temperatures preserve food and corpses by slowing spoilage. Freezing temperatures preserve food and corpses indefinitely, but can also cause hypothermia in living things and eventually freeze them to death. Warm temperatures rot food and corpses, and extreme heat causes heatstroke which can also lead to death.
Outdoor temperature usually fluctuates slowly by day and season and is bounded by the climate of your biome. Be careful though, because unpredictable events like cold snap and volcanic winter can also change outdoor temperature unexpectedly.
Colonists are sensitive when sleeping and become unhappy in a mildly cold or hot bedroom. Clothing can insulate against temperatures extremes and make pawns more comfortable when awake. When faced with temperature extremes, colonists automatically search for and equip any suitable clothing they can find in storage.
All indoor rooms have their own temperature which can be seen by mousing over it. Indoor temperature can be managed through structures in the temperature menu. Keep in mind that heat transfers between rooms and also the outside through roofs, walls, and doors. Large temperature differences, open doors, open roofs, and long thin rooms can make temperature hard to regulate. Larger rooms have more thermal "mass", and their temperature changes more slowly than smaller rooms.
Temperature/heat transfer inside a room is instantaneous regardless of room size. This means long hallways can be used to transfer heat easily through a large base.
Double thick walls and intermediate rooms act as an insulator and slow heat transfer- try using a hallway or storage room to protect bedrooms and work rooms from temperature extremes. Any room that borders an outdoors area transfers more heat, and will usually be closer to outdoor temperature, even if the room borders solid rock.
Try not to build long thin hallways connecting with the outdoors, or leave large solid rock clusters inside your base. This will increase your surface area to outdoor temperature and make indoor temperature more difficult to manage. Cut off outside hallways using doors and mine rock until all traces of outdoor area are gone.
Managing Temperature
Temperature management is important for any colony, regardless of climate. It can be simply managed with a good power supply and the following structures:
Cooler
The cooler is primarily used to lower the temperature of a room. It has two states of power consumption: low and high. In its low state, the cooler produces no heat or cold but still requires 20 W. It can be used to lower the temperature of a room to a comfortable 20 °C (68 °F) (room temperature) in the summer or create a walk-in freezer for your food. In hot biomes such as desert or rainforest, having comfortable air conditioning is a necessity for any base.
Coolers are heat pumps that produce both a cold side and a hot side. The hot side is rarely useful and should be directed to an outdoor space to not inconvenience your colony.
A cooler is theoretically able to cool a single square by about 1800 kelvin [K]. But this is not a linear relation as a room always exchanges heat with adjacent rooms and/or the outside. Example: In a realistic setup, this means it can cool a room with 50 squares by an average of about 36 K per square. So a room with 50 squares and an outside temperature of 60 °C (140 °F) can be cooled down to comfortable 24 °C (75.2 °F) or something near that with a single cooler.
Freezer
A freezer is the most straightforward use of coolers for a starting colony. Building one is as simple as making a room and replacing some wall tiles with coolers. Direct the cold "blue" zone of the cooler inside the room and the hot "red" tile to an outdoor area. Select the cooler temperature settings and reduce their target temperature so that they continue running below 0 °C (32 °F). As the room cools down any food left inside will decay more slowly until it freezes. Frozen food will stay fresh indefinitely and incurs no other benefit or penalty when eaten.
Freezer Tips
Building freezers that can tolerate extreme heat, due to the biome or heat waves, can be challenging. The type of material used to build the walls does not matter because they all have the same insulation values. However, increasing the walls from 1-thick to 2-thick dramatically improves the insulation, but thickness beyond 2-thick does not have a noticeable effect. Never block a cooler's intake or exhaust port or else it won't function.
Freezers lose a great deal of cooling through doors as pawns open them. This loss can be offset by having doors arranged in sequence, one after another, at points of egress, in an "airlock" like fashion. The loss can be examined by mousing over the sections of the airlock to see the temperature. Using doors rather than autodoors can help reduce the cooling lost, though this slows down colonists.
The hot end of the Cooler is useful for climates where the temperature rarely gets above 20 °C (68 °F) and almost never above 30 °C (86 °F). Instead of pointing the freezer's hot end outside, point it directly into your base. This will increase your energy efficiency and may save a few components on Heaters.
Passive cooler
The passive cooler is a very low-tech option automatically unlocked for tribal starts. They operate at the same strength as a Cooler and will cool rooms to a very comfortable 15 °C (59 °F) for 5 days. It needs to be fueled when it runs out of fuel.
Passive coolers are a life saver in extremely hot climates as they can be quickly built, are immune to electrical events and are easily massed in a heat wave. Use passive coolers to keep your living spaces survivable and chill rooms surrounding a freezer to further protect the products inside.
Heater
The heater is used to raise the temperature of a room. It has two states of power consumption: low and high. In its low state, the heater produces no heat but still requires 18 W. It can be used to raise the temperature of a room to a likable 20 °C (68 °F) (room temperature) in the winter or create a walk-in heat trap for your foes. In any cold biome, such as the Tundra, the heater is a necessity for any base.
A heater (in theory) is able to heat a single square by about 1800 kelvin [K]. But this is not a linear relation as a room always exchanges heat with adjacent rooms and/or the outside. This heat conduction effect can be pretty noticeable in extremely cold or hot environments.
Example: In a realistic setup, this means it can heat a room with 50 squares by an average of about 36 K per square.
So a room with 50 squares and an outside temperature of -10 °C (14 °F) can be heated up to comfortable 26 °C (78.8 °F) or something near that with a single heater.
Campfire
Campfires are a quick and dirty solution to produce heat in a hurry. They require no energy, but are temporary structures and must be refreshed with wood every few days. Otherwise they produce the same amount of heat as an electrical heater.
They cannot raise the temperature to over 30 °C (86 °F).
Vent
A vent allows transfer of temperature and gases from one room to another.
Vents can have any building in front of it, but no walls. Vents work best when connecting directly to a climate controlled room. Trying to chain vents across smaller rooms will lead to each successive room getting less effective climate control, and connecting to a hallway won't work well if the hallway is blocked with doors. A vent can be designated to be closed, an action carried out by colonists assigned to flicking.
Steam Geysers
A steam geyser will heat up a roofed room even when covered with a geothermal generator. They are extremely useful for staying warm in frozen climates but can overheat an indoors space in warmer biomes.
Fire Weapons
Weapons that generate fire such as Molotov cocktail and Incendiary launcher can be used to quickly generate heat inside your colony. Under normal conditions this is a bad idea because fires will quickly bring your base to intolerable temperatures. However in a bitter arctic climate with no wood and inadequate heaters, these weapons are your last defense against freezing to death. Draft your colonist and force them to open fire on an empty space, or burn spare corpses and rags to increase heat output.
Doors
Similar to double thick walls, double doors (not side-by-side, rather, both in the path of travel) improve insulation and reduce temperature equalization. A door can be left permanently open (mark the door to 'hold open' and have a pawn pass through) to help control temperature. Open doors allow temperature to more quickly equalize between rooms, or outdoors for exterior doors. Equalization through open doors is less potent than vents.
Solar Pinhole
 | This article relates to content added by Royalty (DLC). Please note that it will not be present without the DLC enabled. |
Solar pinhole is a psycast that creates heat and light. It lasts five days. It is useful for emergency situations, such as power shortages during cold snaps.
Extreme Temperature Effects
The maximum temperature is 1,000 °C (1,832 °F) and the minimum is -270 °C (-454 °F), very close to absolute zero. The minimum temperature is not encountered during normal unmodded gameplay, but fires in small enclosed spaces can reach the maximum temperature. The gear tab also shows aggregate stats about comfy temperatures.
There is an orange glow when hovering over very hot areas to help you identify them. In these areas, it is so hot that flammable objects will spontaneously catch fire, and pawns will be burnt by superheated air.
On pawns
Temperatures below a pawn's minimum comfortable temperature or above their maximum comfortable temperature will cause them discomfort with mood debuffs and in extreme cases can cause death. The simple cure for any afflicted colonist is to return them to a normal temperature environment. This process can be sped up by forcing the colonist into the opposite extreme, such as putting heatstroke victims in a freezer to cool off.
Ailments include:
- Heatstroke - caused by prolonged exposure to heat.
- Burns - caused by exposure to extreme heat or contact with fire.
- Hypothermia - caused by prolonged exposure to cold.
- Frostbite - injury to extremities caused by prolonged exposure to cold.
On objects
Objects such as wooden structures and furniture will ignite once they reach a high enough temperature, depending on their material's flammability. All stone types and uranium have their flammability set to 0% and therefore objects made from them will not ignite or burn in any temperature. Steel, plasteel, silver, gold and jade are flammable as materials, but not as items.
Extreme cold has no negative effect on objects; most food and plant matter items spoil depending on temperature, and become refrigerated at temperatures below 10 °C (50 °F), slowing down the spoiling process. When temperature reaches freezing (0 °C (32 °F)), they become frozen and completely stop spoiling.
Temperature Thresholds
It is important to know where Temperature might become an issue. Often multiple aspects have to be considered with Temperature: Pawn Limits, Sleeping Pawn Limits (which exclude clothing values), Workbench Limits, Plant Limits.
For example, the highest and lowest temperature pawns can survive is way above and below the temperature for plant growth and the temperature range of most workbenches. In extreme heat, even the spontaneous Combustion of Building Material becomes an issue.
- 1000°C (1832°F) maximum value
- ~235°C (~455°F) Items spontaneously catch fire
- 50°C (122°F) Animals max temperature
- 44°C (112°F) Plant growth slowed
- 30°C (86°F) Campfire max temperature
- 26°C (~79°F) default human upper limit
- 21°C (70°F) Heater and Cooler default target
- 16°C (61°F) default human lower limit
- 15°C (59°F) Passive Cooler min temperature
- 10-1°C (50-34°F) Plant growth and food spoiling slowed
- 5°C (41°F) bad temperature bench modifier
- 0°C (32°F) Plant growth and food spoiling stopped
- -10°C (14°F) Most plants die
- -273°C (-460°F) minimum value
Room Temperature Mechanics
Temperature mechanics
Equalisation calculations happens once every 120 game ticks.
All internal calculations are done in celsius. Fahrenheit is simply a different way to display the same absolute value.
Temperature seems to be measured to a extreme precision. A outdoor of -9 °C (15.8 °F) and a room of 2,000 °C (3,632 °F) have a difference around -9555.292C
Outside
Spaces that are not enclosed are simply considered "outside". The outside temperature is defined entirely by the climate and storyteller. No amount of heat adding/removing can change it, not even the Mod Tools can change it by simply adding/removing heat to the outdoor "room" - unless they set it for the entire map, nothing will happen. Proximity to heatsources does not mater. Instead the "outside" value is used.
Despite this "outdoor" is still used like any other neighbouring room for wall equalisation. And often the most important room for that mater.
Rooms can be in one of 3 states:
- Unroofed (not a single roof tile). This means it will simply use outdoor temperatures. It does still count as a "room" for most game mechanics, but for temeperature mechanices every active tick it will set to outdoors temperature regardless of difference.
- fully roofed (all tiles in the room have a roof tile). These rooms are entirely subject to heating, cooling and temperature equalisation
- partially roofed (uses outdoor temperature) while this room seems to maintain temperature while paused, the next equalisation tick will simply set it to outdoor temperature as a fully unroof one
- partially roofed (not use outdoor temperature) While there will be significant equalisation via the (lack of) roof, the room still has its own temperature calculation. The exact flipover point between this and "uses outdoor" is not static and seems to change with roomsizes. Possibly something based on the summed "no roof equalisation" value. < 1/4 of all roof tiles seems to be the limit.
Passive Equalisation
This is equalisation via walls and roofs.
Walls will equalize towards the room on the other side. This can be another fully realized room or simply the outdoors. If the other side is not outdoors, that room will also equalize towards this room.
- The material of the walls does not matter. Wood is as isolating as any stone or metal. And unmined rocks are equally effective.
- The surface area does seem to matter. Basically, the game is using a 2D variant of the square/cube law, with walls taking the place of "surface area" and room size taking the place of "volume". As such square rooms are the most efficient at keeping temperatures.
- A 2nd layer halves the temperature equalisation via walls. Adding more than a 2nd layer of wall does not seems to have any effect.
- Furniture acts highly variable for this and even just the definition what is a room. Nutrient dispensers are one of the few items working fully like walls for equalisation purposes
Example wall equalisation values at -9555.208C difference:
- 1x1: -161.470°C
- 2x2: -81.235°C
- 3x3: -54.157°C
- 4x4: -40.618°C
- 5x5: -32.494°C
- 6x6: -27.078°C
- 7x7: -23.210°C
Example double wall equalisation values at -9555.208C difference:
- 1x1: -81.234°C
- 2x2: -40.617°C
- 3x3: -27.078°C
- 4x4: -20.309°C
- 5x5: -16.247°C
- 6x6: -13.539°C
- 7x7: -11.605°C
Roof is a major part with equalisation with the outdoor temperature. It will always equalize with the outdoor temperature, regardless what the room borders. However, the equalisation rate is also constant for all room sizes at the same temperature difference. There are 4 basic types of roof:
- unroofed
- Constructed (Thin Roof)
- Thin Rock (Thin Roof)
- Thick Rock
- Thin Roof at a difference of -9555.208C it is -57.331°C.
- unroofed tiles are looked at in relation to the total count of roofed tiles. With at least 1/4 unroofed the room will simply equalize to outdoor temperature on the next tick.
- thick roof isolate the same as thin roof. However, they also add a cooling effect if indoor temperature is above about 15 °C (59 °F); this effect is extremely small compared to other sources, however
Active Equalisation
While Vents, Coolers and open doors still keep rooms separated, they also equalize temperature at a very high rate. This rate is unfortunately not shown on any tooltip.
Torches, Campfires, Heaters and Passive coolers will directly modify the room temperature instead, adding/removing heat every equalisation tick as appropriate for their settings/current state.