Ships Air Recycling

For each atmosphere type within the ship there will have to be some sort of purification being caried out which will cleanse the atmosphere. We will explore this further as we progress with the simulation, but for the time being we will look at humans. As humans breath in and out we naturally contaminate our atmosphere with CO2. The air on the ship is normally made up of 78% Nitrogen, 21% Oxygen and about 1% others including CO2. When the CO2 levels rise above 1%, crew members (who are not in space suits) will start to become drowsy. When this rises to 10% unprotected crew members will become unconscious, and if left in that environment will die.

The formula for this is:

CO2PercentageEfficiencyFactor =100 – (100 * (CO2Level – 1) / 9)

To make things simple we will assume that like the heating each 100 square meter of floor space has an atmosphere scrubber built into it. Normally the CO2 scrubbers will clean the air in any given section of the ship by 10% per minute. Each crew member in a section will increase the CO2 by 0.1%. Therefore the scrubbers will easily accommodate 100 people in each section. Note that because air circulates this work will be averaged out with adjacent sections. So one section sided by 4 other sections would handle 500 people. This seems like overkill, however it has been noted on the Star Trek show that there are lots of redundancies in the life support system (this makes sense).

Damage to any section of the ship might result in damage to the CO2 scrubbers in it. Due to the redundancies mentioned the damage will not have any effect until the health of the scrubber falls below 50%. At this point the amount of CO2 that can be scrubbed is calculated by the following formula:

CO2ScrubbedPerMinute = (10 * ScrubberHealth/50).

This means that a scrubber down at 10% health can still scrub 2% per minute – enough to keep 20 people alive.

Power Requirements

Each scrubber uses 0.1MW regardless of whether it is scrubbing the oxygen or not. If the ship has 100,000 square meters of floor space, then the scrubbers will consume about 100MW.

Dev Notes

In the Star Trek TV show, on certain occasions power was diverted from life support to help the ship. This implies that they do consume a reasonable amount of energy. This can be carried out for a temporary boost in power. For example: Assuming the scrubbers are at 100% and we have 10 people in a section. If the captain cuts power to the scrubbers over the whole ship, it will be 1 minute before they start to feel the effects of the CO2 and 10 minutes before they become unconscious. At this point, if he turns the scrubbers back on, within one minute they will have restored the ships atmosphere to normal and people will recover.