Greenhouse CO2 Dosing Calculator

Summary

This calculator determines the CO2 gas flow rate (L/min or ft³/hr) and total daily volume needed to raise and maintain a greenhouse atmosphere from ambient CO2 (typically 400 ppm) to a target enrichment level (800–1500 ppm). Enter the greenhouse volume, air exchange rate, target CO2 concentration, and planned injection duration to get actionable dosing figures.

How it works

1. Enter the greenhouse internal volume (length × width × height, or total cubic meters/feet).
2. Set the ambient CO2 concentration (typically 400 ppm outdoors).
3. Set your target CO2 concentration — most crops benefit from 800–1200 ppm during daylight.
4. Enter the air infiltration/exchange rate (air changes per hour) — typical unventilated greenhouses are 0.5–1.5 ACH.
5. Enter the planned injection duration in hours per day (usually aligned with daylight hours).
6. The calculator derives the CO2 mass needed to raise the volume, adds the continuous replenishment flow to offset leakage, and outputs total flow rate and daily volume.

Use cases

• Sizing a CO2 generator or compressed CO2 cylinder system for a hobby or commercial greenhouse.
• Estimating daily CO2 gas consumption and cylinder refill frequency.
• Comparing enrichment costs between propane burners and bottled CO2 at different target ppm levels.
• Planning CO2 dosing schedules for seedling propagation, vegetative growth, or fruiting stages.
• Checking whether an existing CO2 system can maintain target concentration in an expanded structure.
• Teaching horticulture students the mass-balance approach to greenhouse gas management.

Frequently Asked Questions