An investigation into the effects of fluegas quality on the performance of greenhouse crops

This project aimed to investigate the link between the quality of CO2 enrichment gases and the yield and quality of greenhouse crops. The concentration of harmful pollutants in the greenhouse is dictated largely by the combustion system from which the flue gases are used. The hierarchy of 'bad' to 'good' was established.   Most pollutants Least pollutants
The ‘safe’ concentration of NOx in flue gases depends on the concentration of CO2 in the flue gases, which varies according to the combustion system type and fuel used. It also varies according to the CO2 concentration achieved in the greenhouse. If 1,000ppm of CO2 is achieved in the greenhouse, the concentration of NOx in the flue gases from a natural gas fuelled boiler should not exceed 30ppm.
Evidence also suggests that more precise control of CO2 levels in the glasshouse could reduce crop risks from pollutants, optimise crop response to CO2 and reduce unnecessary fuel use.

The objectives of this project were to: 1. Establish values for the concentrations of harmful gases in the environment of five representative commercial greenhouses, 2. Establish the effect of CO₂ enrichment system on the presence of harmful gases. 3. Determine the effects of harmful gas concentrations on plant yield and quality.