Most tables in books I have looked at say that one average human requires 2600 grams of food, 686 grams of oxygen ( O2) and 400 grams of water. They then produce 857 grams of CO2, 857 grams of water and 1972 grams of waste. At standard temperature and pressure, the equivalent volume of oxyfgen is about 50 liters per hour.

I was surprised to discover how hard it was to find similar statistics for plants. One source says that a single plant leaf produces about 0.005 liters per hour, so you need about 50/0.005 = 10000 leaves which would be provided by about 500 plamnts or so..for one person.

The efficiency of plants to produce oxygen varies quite a bit. It is also possible to make an artificial process involving photosynthesis that would effectively do the same thing but it wouldnt be a pretty to walk through!

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