A greenhouse environment control system generates a CO2-enriched air which is supplied to a greenhouse at a controlled temperature suitable for plant growth. An absorption chiller reduces temperature of a CO2-containing stream of processed gasses from an engine. A mixing and blending unit maintains CO2 at an acceptable concentration for enhanced plant growth and human occupation. An HVAC system modulates temperature and positively pressurizes the greenhouse with the CO2-enriched air to reduce risk of contaminant intrusion. Misting further controls temperature. Retractable shades regulate light supplied to plants and solar gain.
