Hydroponics
Hydroponics is the growth of plants in a liquid medium, rather than soil. Plants are often supported at the stalk, leaving the roots free floating. In other cases, roots may be supported by inorganic media, such as plastic pellets, gravel, or mineral wool. All nutrients are supplied through the liquid.
The liquid is held by vessels or pipes, that include a circulation system with automatic renewal and filtering. All parts that are in contact with the liquid are cleaned or replaced in regular intervals. The plants are in placed in trays, that can be stacked many layers high for increased density. Production rates can be increased for certain plants with multiple growth cycles per year.
Using container shaped spaces of 40x8ft (30m2) hydroponic installation in 2023 can produce 2/6 tonnes of produce per year, depending on the crop, using an average of 200 kWh/day, or 270 W/m2. On an area basis, yields for suitable crops range from 600 to 2000 tonnes per hectare, or about 10 to 20 times more than for field grown crops.
Contents
Advantages
This method provides several advantages to a colony on Mars:
- Disease Control
- Increased Crop Yield in terms of yield per hectare and in terms of kWh of lighting per tonnes of yield.
- No influence from exterior weather, no influence from dust storms.
- With nuclear power can be entirely independent of the environment, seasons, storms, etc.
Disadvantages
While a natural soil based environment can stabilize itself if the yields are not too high, the hydroponics require technological support and regular maintenance:
- Artificial fertilizer and other auxiliary substances (antibiotics, cleaners, acidity regulators, etc. ) needed, which requires a chemical industry behind.
- Cleaning and disposal of toxic degradation products.
- Higher manual maintenance effort.
- Not applicable to all kinds of plants.
- Requires artificial lighting/heating that needs to be produced by an external power source.
Plants that can be grow in hydroponics
Herbs, lettuce, spinach, Bok choy, tomatoes, cucumbers, celery, peppers, strawberries, watercress, wheatgrass and other sprouts. Cereals can be grown hydroponically on Mars, although not an economically viable proposition on Earth.
Plants that cannot be grown in hydroponics
Corn, potatoes, sweet potatoes, carrot, turnips, beets, vines (raisin), cabbages, pumpkins, squash and melon. Fruit trees.
