Under un-enriched conditions, commercial greenhouse daytime CO₂ concentrations regularly drop to 250–320 ppm due to aggressive photosynthetic consumption by mature canopies, severely limiting Rubisco carboxylation velocity ($V_{c,max}$). Enriching the microclimate to 800–1,000 ppm boosts net carbon assimilation by $+25\% \text{ to } +35\%$.
1. The Ventilation Purge Dilemma
When roof vents open beyond 20% to control heat and humidity, convective air exchange expels up to 60–80% of injected CO₂ to the external atmosphere. Sizing dosing rates and choosing between pure liquid CO₂ ($0.25–0.35/kg) and natural gas CHP flue gas ($0.05–0.08/kg) dictates overall farm profitability.
2. Interactive ROI Optimization Tool
Determine your optimal dosing rate and net daily dollar profit per hectare: