CO2 Enrichment

Horse manure used for CO2 enrichment in a greenhouse. Picture taken at Ecovillage Sieben Linden, Germany.

While the average ambient CO2 concentration in the atmosphere is now (2016) about 400 ppm, it can be increased to much higher levels in a greenhouse to improve plant growth. Concentrations of 1000-1200 ppm or even up to 1500ppm are used in commercial greenhouse operations. Above this level, dangerous toxic effects to the crops and workers are more likely to occur. This enrichment may have very positive effects on crop productivity. However, the available information regarding concentration/effect is quite variable. Some reports claim a doubling or tripling of photosynthesis. Other potential advantages are lower water use due to changes in plant transpiration with lower water losses. Various CO2 sources are available, such as biogas or compost which provide very clean CO2. Some pyrolysis methods (for biochar production) are also very clean and could be considered as well.

Open Source Hardware Needs

• CO2 sensors
• pipes, fans

External links

• Wikipedia: (section in greenhouses page) CO2 enrichment in greenhouses
• Wikipedia: (section in CO2 page) Agricultural and biological applications
• OMAFRA: "Carbon Dioxide In Greenhouses"