Oxygen Guide

This Guide is intended to keep your Duplicants from suffocating. It will compare different ways of providing Oxygen to your colony. It will also look into handling CO2 gas resulting from breathing and some structure waste products.

Good to know

• A Duplicant consumes roughly 100g Oxygen per second.
  
  
• Duplicants with Mouth Breather trait require double the oxygen, 200g/s.
  
  
• Duplicants with Diver's Lungs trait require 25g per second less, 75g/s.

The gases mix, but they divide into layers according to their weight (left in the normal view, right in the oxygen overlay):
Keep in mind, that every substance in the gaseous state is assigned a certain weight. It defines whether a given gas will rise or fall if there is more than one type of gas in the room. When there is only one kind, it will strive to fill the entire room. Unlike real air, there is no such thing as the mixing of gases. This means that there can be only one type of gas in a given field (the same applies to solid and liquid matter). If there are several gases of similar density in one room, they will form layers.

Hydrogen will be located the closest to the ceiling, being the lightest gas. Then there will be a mixture of pure and polluted oxygen (though most often pure oxygen will be above the contaminated layer). Next, there is steam, chlorine and the heaviest gas: carbon dioxide. Keep this in mind when planning your base and designing rooms. It is worth to have, e.g. a small basement, where carbon dioxide will be able to calmly descend, without poisoning the main rooms.

The Beginning

When your Duplicants appear in your colony on Cycle 1 they can only breathe what is provided, which is mainly a small supply of Oxylite in the Dirt Biome, where you start. It will be exhausted within just a few cycles and there is no way you can rely on it as a permanent solution. But no worries, you can build an Algae Deoxydizer right away and you can research a few additional structures that will replenish your oxygen more effectively. Get your Research Station up and running!

Converting Algae to Oxygen

Algae Deoxydize

The quickest solution is the Algae Deoxydizer which converts Algae and Power into Oxygen (and heat). One of those theoretically can support up to 6 Duplicants, but because the oxygen doesn't flow away easily it will run into over-pressure quickly and stops working temporarily. In most cases, one Deoxydizer for every three Duplicants seems to be a good choice.

PRO:

• Algae isn't used for anything other than oxygen production.
  
  
• Your precious Water is not required for this; all it needs is a Duplicant running a Manual Generator and a Duplicant refilling the Deoxydizer with Algae.

♥♥♥:

• Algae is not an unlimited resource (unless you do the Puft+Morb combo, which is highly impractical). However, you can find pockets of it in the Toxic and Slime Biomes if you send out expeditions.

Algae Terrarium

Algae Terraria produce Oxygen from Algae and Water. Each one produces Oxygen with a rate of 40g/s - or 44 if under light. You need at least three for each Duplicant (5 per 2 Duplicants) if you want to rely on them as Oxygen source.

PRO:

• Consumes no power, less Algae than the Deoxydizer, and some Water instead.
  
• Consumes some Carbon Dioxide too, if present (See below in the Carbon Dioxide Removal section).

♥♥♥:

• Needs more instances of it per Duplicant, which comes with more Delivery jobs.
  
• Produces far less Oxygen from Algae and Water than would have been produced by using a Deoxydizer and Elecrolyzer separately. The Electrolyzer would produce 266.4 g/s of Oxygen with the same amount of water, while the Deoxydizer will get an additional 18 g/s from the algae that would have been used in a Terrarium.

Shortage of Algae

Algae is one of the rare resources, but it can be refined from Slime using an Algae Distiller. This process produces Polluted Water as waste and handling slime involves having to deal with Polluted Oxygen. The Bio Distiller has an output of 100g/s of Algae, which means under optimal conditions you would need ten Bio Distillers to satisfy the needs of one Deoxydizer. This also means your Power needs skyrocket. Under this perspective the Bio Distiller is less a supplier of Algae than it is a Slime remover (to avoid Polluted oxygen after digging through the Slime Biomes).

Converting Water to Oxygen

This one requires multiple research items - You need to gain the Electrolyzer for the process, but to supply it with Water you need to have at minimum Liquid Pipes and Liquid Pump researched, and to move the resulting gases to where you need them you need a Gas Pump, Gas Pipes and Gas Vents. You will have to cope with Hydrogen gas as well, that needs to be kept from spreading through your base. The best option for now is to burn it in a Hydrogen Generator, which requires further research and thoughts on separating the gases. But it gives you back some energy that is required for the electrolysis process, the pumps and Gas Filters.

One Electrolyzer provides 888g/s of Oxygen per second under optimal conditions. That is enough for up to 8 Duplicants if you have a steady supply of Water and Power, and the Gas is moved quickly enough away from the Electrolyzer (it will stop when the gas pressure around it is too high).

PRO:

• You need fewer Electrolyzers per Duplicant.
  
• Duplicants do not need to manually deliver anything to the Electrolyzer.
  
• From the beginning there should be enough water to keep your base running for about 100 cycles - then you need to find other ways of providing water.

♥♥♥:

• You need to build pipelines to provide Water, and you need to move the gases away quickly to run at high efficiency. One Electrolyzer produces enough gas to keep two gas pumps busy.
  
• You need to separate the Hydrogen from the Oxygen, since Hydrogen is an unbreathable gas. It has its uses, but freely floating through your colony is not one of them.

Shortage of Water

Water Purifier

This is one of the obstacles to tackle roughly when you hit cycle 100, because Water is used for Research, Food and Hygiene as well. After a while you will have to convert Polluted Water into Water again. You can use the Water Purifier for this - the output of one Water Purifier is enough to feed five Electrolyzers. But it requires manual supply of Filtration Medium, removal of Polluted Dirt which usually requires two Compost places per Water Purifier, and, of course, power. If this sounds like it'll keep your Duplicants busy, it will.

Steam Geyser

Another option is to consume water from the Steam Geyser, if you find one. It is an infinite source of Water - but it is hot. Moving hot water into your base will heat it up, so you need insulated pipes for that; electrolyzing hot water results in hot gases, so you will need to cool either the water or the gas. For gas cooling you can apply Thermo regulators, for cooling down Liquids you need to design yourself a coolant system, and at the current state of the game it takes a long time to cool down liquids. A quicker way, but not a permanent solution is to drop Ice and Snow into your hot water.

Distillation

If you do not have access to a Steam Geyser, you could develop a water distillery. If you heat Polluted Water to its boiling temperature, it becomes Steam which condensates back to Water- Hot Water, to be exact, so everything said about Steam Geyser above is valid for this solution too.

Carbon Dioxide Removal

Carbon Dioxide (CO2) is a waste product of Duplicants breathing, from burning Coal in a Coal Generator, or burning Natural Gas in a Natural Gas Generator. It is an unbreathable gas and so makes your Duplicants hold their breath, stressing them and interrupting their sleep (which stresses them even more) and work. Luckily, because of its weight, it has a tendency to drop to the bottom corners of your colony and forms pockets of unbreathable gas there. At the beginning of the game you will be fine as long as you have a low spot in your colony where Duplicants rarely have to go.
Duplicants exhale 2g/s of CO2 which is very little, compared to the 100g/s of Oxygen they inhale.

Algae Terrarium

When your CO2 pockets start to become worryingly large, you might start to control them with Algae Terraria. Each one consumes 1/3 g/s of CO2, so you'll need 6 of them for each Duplicant in your colony. They produce Oxygen, too, with a rate of 40g/s - or 44 if under light.
It needs to be regularly, manually supplied with Algae and Water. If submerged in water, it can take the water from its surroundings instead. Considering the number of them required per Duplicant, and all the Delivery jobs required by them, they are not a good solution for a growing colony.

PRO

• Quickly available
  
• No power wires or water pipes required

♥♥♥

• Dependent on Water and Algae, which will become scarce.
  
• Many instances required, resulting in lots of Delivery jobs.

Air Scrubber

Once the CO2 pockets turn into CO2 caverns and clog the lower areas of the base, it's worth investing in the Air Scrubber. Just one should be enough for a longer while. It consumes 300g of Carbon Dioxide per second, which is enough for 150 Duplicants - under the idealistic assumption that the colony does not burn Coal or Natural Gas in a Generator.

PRO

• Doesn't require any maintenance (other than repairs in case of accidents)
  
• Doesn't require a gas pump nor a filter
  
• Just one instance removes enough CO2 to satisfy the needs of any feasible colony that doesn't use gas generators (those that do rely on gas generators will need more than one)

♥♥♥

• Pollutes water
  
• Has non-negligible electricity cost

Slickster

A captured Slickster will consume up to 250g/s of CO2 and turn it into Crude Oil.

PRO

• Produces Crude Oil
  
• No maintenance or resource usage

♥♥♥

• The Slickster will die if its body temperature drops below ~35C

Gas-To-Liquids

Carbon Dioxide can be cooled down to its Dew Point temperature (-48.1°C) to become a Liquid. Why should you do that? Mostly because the limits of Pressure gas can have to let a Gas Vent release its content. The game restricts it at 1800g of any gas in its tile. This can be gamed (see next section) but it is more of a challenge to accept it and work around it. 1800g of a Gas is not much. the same tile could hold hundreds of kg of a Liquid. If you create a Container for Liquification with an inner size of 10x10 tiles, this could hold about 60,000 kg of CO2 (you can store 600kg Liquid Carbon Dioxide per tile). Probably more than you will ever produce: One Coal plant produces 20g/s of Carbon dioxide, and if you continuously run 10 of them you would produce one kg of it every 5 seconds, or 120kg per cycle, this would reach for 500 cycles.

To cool down the gas you need something cooler than itself that transfers the heat away. The mostly used solution is to pump very cold Hydrogen gas through a loop of gas pipes made of a material with good heat conductivity through the gas container you want to cool down. Hydrogen is best choice due to its low Dew Point (-252.2°C). To cool the Hydrogen down you can use Thermo Regulator. Using Wheezewort is not recommended as it does provide very little cooling effect - it is mainly a decision of what you have more of, time or energy. The Thermo Regulator cools down Gas passing through it by 14°C but it heats up doing so. Cooling it down with a Hydrofan is likely required. It is recommended to have a little container of Hydrogen gas in your "Freezer" to switch off the Thermo Regulator in the loop if the reservoirs temperature drops below -220°C - it would be annoying to get Hydrogen gas become liquid in the gas pipes and cause material damage.

PRO

• You can boast on the Klei User Forum about your clever design

♥♥♥

• Quite some power required to drive all the pumps, filters, thermo regulators involved
  
• You need to find a solution what to do with the heat emanating from the Thermo Regulators. (Maybe steam production in a Water distillery?)

Compression

This actually a gaming trick. To circumvent the fact that a Gas Vent only vents when its tile has a pressure of less than 1800g, the gas needs to be replaced quickly. And having some drops of liquid on its tile helps on this. Liquid present, Gas gets pushed to a neighbor tile immediately, ignoring existing pressure. The Tile under the Gas Vent becomes free again and can vent. The pressure in such a chamber can be risen almost indefinitely.

PRO

• No power required for storing the gas away

♥♥♥

• Kind of cheating

Pump to outer space

Available since the Cosmic Upgrade, one can pump any unwanted liquids or gases to outer space. Keep digging upward until you find some regions where the info says it's exposed to space. Build Mechanized Airlock or Manual Airlock before going to this region to prevent accidentally draining your precious gas. Simply pipe unwanted gas here with a Gas Vent as output. The space very efficiently destroys gas. One can even build it without any complicated equipment like Exosuit and just let them holding breath for a little while, since building some pipes and vent is quick.

PRO

• Require little / none energy to build
  
• Require little technology
  
• Works for other unwanted elements, e.g. Chlorine

♥♥♥

• Takes some time to dig upward (if it counts as a ♥♥♥)

Piping (Gas or Liquid)

This section is intended to explain some aspects of Fluid Piping (Gas or Liquid) that are not necessarily obvious. These aspects can both lead to frustrations with designs not working when they are not understood and can offer very useful mechanics when employed properly.

Flow

Fluids are transmitted through pipes using "packets". Each tile of pipes can contain only one packet and each packet can consist of only one type of fluid. Packets will only flow from one pipe tile to another if there is both:

• A building pushing the fluid
  
• A building capable of recieving fluid
  
• A pipe that can accept at least part of the packet

Examples:

• A pump connected to any number of pipes but nothing else will not pump.
  
• A vent connected to any number of pipes but nothing else will not empty those pipes.
  
• A pump connected to a tank through a series of pipes will pump until the tank is full and all pipes leading up to the tank contain a packet.
  
• If a tank is full and the pipe connected to it contains 5 kg of water and the pipe before that contains 8 kg of water then the second to last packet will send 5 kg of water to the last pipe to fill that packet. (Provided there is something pushing the liquid).
  
• If in the same setup the 5 kg of water are followed by 8 kg of polluted water then the packets cannot merge.

Junctions

Most pipes will lead to more than one destination and often enough will also have more than one source. Advanced schematics can also contain loops. This leads to many junctions and understanding the behavior of these junctions is important.

Pure Pipe junctions

Junctions that consist of only pipes operate on an alternating pattern. If there are 3 inputs and one output then the junction will take a packet from each input pipe in sequence over and over again. Conversely if there are 3 output pipes then the junction will send one packet to each output pipe on sequence over and over. The sequence is predictable but not intuitive.

Pipes and buildings

When a pipe passes through the input or output node of a building the handling of packets changes dramatically. The input node (white symbol) of a building (bridge, vent, hydroponic farm plot) will always take priority IF the building can accept a packet. The output node (green symbol) of a building (bridge, pump, water sieve) will always yield priority to any incoming pipe.

Examples:

If you imagine two horizontal lines of pipes going in parallel with one tile separating them. They each do their own thing which doesn't concern this example. Now you put a bridge going from the upper line to the lower line. The effect of this is that:

• If liquid is flowing in the upper line but not in the lower line then the bridge will take all packets from the upper line as long as it can output them in the lower line.
  
• If liquid is flowing in both lines with only full packets then both lines will flow uninterrupted and the bridge will do nothing. This is because everytime there is a packet for the bridge to take there is also a full packet at the other side which takes precedence.

Useful patterns

Infinite loop

If you just build a loop of pipe and add the output of a bridge this loop will not fill, nor would any liquid inside that loop continue to flow. However if you build a loop of pipe and substitute on pipe tile with a bridge then the loop can both accept packets and will move them around because all three criteria for flow are satisfied (building output, building input, free pipe)

This can be used to pump a coolant medium between an area that needs to be cooled and a central room where medium is cooled back down. It can also be used to build buffers and filters.

Top-Up junction

If you need to supply a fluid to a network and have two sources available but you prefer to use one source over the other whenever possible you can use a top-up junction. To do this feed the primary source directly into the network and the secondary source via a bridge. As long as the primary source can satisfy the demands of the network the bridge will be blocked and the secondary source will not be used.

Overflow junction

If you have a source that can more than adequately supply your network and you want all surplus fluid to be diverted somewhere else you can use an overflow junction. To do this you pipe your source directly to whatever place you want your overflow to go to. Then you connect your main network to the source via a bridge. Now, as long as the primary network has demand for the resource the bridge will asure that all packets will be sent there. Only when the primary network is full will the bridge become blocked and surplus packets can find their way to some other place.

Implications

Every other situation is just a specific case of the above mentioned rules but there are a few that warrant mentioning:

• Do not run your pipes directly through inputs like hydroponic farm tiles. If you do this the first farm plot will starve all successive plots because it takes priority over them.
  
• Do not run your pipes directly through several outputs. If you do this you risk blocking the building. (The building cannot output if there is a full or incompatible packet in the pipe).

Final Notes

Thanks to Oxygen Not Included Wiki and friends for providing information for this guide.










------------- Video Game History Curator ------------------------------ Video Game History Steam Group -------

[DanishScorpio]

Then your in luck:

https://steamcommunity.com/sharedfiles/filedetails/?id=1467950246

[FacePlant999]

This is very useful. I always struggle early on, so this helps a lot. Now just need a guide for food :thinking:

[Gary]

with the pump to outerspace, if you dont have exosuits i know its possible to do it cus they can just hold their breath but what if you come across slimelung? if you dont have exosuits i think you will not be prepared for slimelung

[DanishScorpio]

Thanks Mariana

[Mariana]

This is great! Thank you!

[Thetramp]

compression co2 removal doesn't seem to work for me, the liquid just dissapears after pumping for a minute or two

[6FINGERDEATHPUNCH]

cool

[Typical Chinese]

Nice