Plan B: Terraform oxygen

Oxygen is a natural resource used to support growing cities in Plan B: Terraform. The resource becomes available at Level 4, making it one of the first major logistical requirements after the opening industrial phase. It is extracted from the atmosphere rather than mined from a deposit, so your main challenges are building the correct production chain and transporting the gas to the cities that need it.

The official Oxygen resource page classifies oxygen as a natural resource and identifies its resource ID as o2. In practical terms, this means you should treat it differently from iron, sulfur, or aluminum: oxygen does not require an extractor placed on a mineral patch.

Video Highlights:

• Choosing higher ground helps protect early industrial areas from future oceans.
• Atmospheric Extractors support oxygen and carbon production.
• Separate Supply Centers make city logistics easier to monitor.
• Oxygen demand changes as plant life spreads across the planet.

Oxygen production competes with carbon production because an Atmospheric Extractor can be assigned to one output at a time. Avoid converting every extractor to oxygen immediately. Instead, keep enough carbon production for polymer-related chains while adding dedicated oxygen capacity for your cities.

The simplest oxygen chain is an Atmospheric Extractor connected to a Depot, followed by transportation to a city Supply Center. Oxygen itself does not need a Factory or Assembly Plant for production. Your industrial buildings are used to create the extractor, depots, roads, trucks, and supporting infrastructure.

Use this setup when a city first begins requesting oxygen:

The recommended ratio is not a permanent fixed formula because city demand changes with population and atmospheric conditions. Start with one Atmospheric Extractor, observe the city requirement, and then add capacity before the city reaches a shortage. A small buffer at the receiving depot is useful because truck routes may not deliver continuously.

If a route points in the wrong direction, reverse the start and end locations using the route controls. This is especially useful after redesigning roads or moving a depot. Confirm the trucks are traveling from the oxygen source toward the city rather than returning with empty or misdirected deliveries.

Cities begin consuming oxygen at a population of 10. Early demand is modest, but it increases as the city develops. The official resource data shows oxygen being used by Supply Centers alongside concrete and reinforced concrete at different population ranges. This makes oxygen part of a broader city-support system rather than an isolated production objective.

A reliable city logistics layout uses separate resource channels:

• One supply center for oxygen.
• One supply center for concrete or reinforced concrete.
• A dedicated receiving depot for each major input.
• Roads that remain accessible as the city expands.
• Extra trucks reserved for resources with rising demand.

The most common scaling mistake is increasing extractor output without improving transportation. If your production depot is full while the city reports low oxygen, the problem is probably route capacity rather than production. Add trucks, improve the road connection, or replace older storage with higher-level depots when available.

Depot Mark II becomes especially useful once unlocked because it offers greater range and transport capacity than the original Depot. Depot Mark III later improves the same logistical pattern further. Upgrading storage can reduce the number of small disconnected routes and make large industrial zones easier to manage.

When the planet begins becoming greener, review each city rather than applying the same change everywhere. A city with strong plant coverage may need less imported oxygen, while a developing settlement elsewhere may still depend on its supply chain.

Oxygen is both a city input and part of the wider terraforming progression. As your population grows, you gain access to systems that spread vegetation and improve the planet’s atmosphere. Trees and other plant-life systems gradually create more breathable conditions, which can reduce the amount of oxygen that cities need from imported production.

The progression is not an instant replacement for your industrial network. Your early cities still need dependable oxygen deliveries while forests expand. Treat atmospheric improvement as a gradual reduction in logistical pressure rather than a reason to stop monitoring supply.

Tree placement also affects how much space remains for factories, roads, and logistics. Keep production areas compact and organized so vegetation can expand around them without forcing constant reconstruction. Higher ground is useful for factories, while future forests and fertile regions can be reserved for terraforming systems.

As the city grows, do not allow oxygen infrastructure to block roads or future supply routes. A dedicated industrial district with space between production sectors makes it easier to add new extractors and depots. It also leaves room for later rail infrastructure when trains become available.

Once trains are unlocked, consider moving high-volume oxygen routes away from crowded truck networks. Trains require a loop and dedicated rail infrastructure, but their greater capacity can support large cities more efficiently. Keep one clear production area for oxygen and connect it to a city-side receiving area with enough room for future expansion.

Oxygen problems are usually caused by one of four issues: insufficient extractors, incorrect production assignments, inadequate transport, or a city-side receiving problem. Check the entire route before adding more buildings.

A practical maintenance routine is to inspect oxygen whenever a city reaches a new population milestone. Compare the city’s required amount with actual delivered supply, then check whether the delivery rate remains stable over time. If oxygen demand has fallen because of plant life, redirect some Atmospheric Extractors to carbon for polymer production.

Keep a small reserve of construction materials nearby so you can expand the route without interrupting the city. If roads or factories become submerged as terraforming progresses, use the map’s alerts to locate affected infrastructure and rebuild it on safer ground.

The official Plan B: Terraform Oxygen page remains the best reference for the resource’s unlock level, production building, and listed production uses. Use it alongside your in-game production panels because city demand and overall logistics depend on the current state of your colony.