The goal is not a cool greenhouse, it is a crop that transpires steadily all day. That means managing heat, humidity, and carbon dioxide together.
Solar load is the dominant challenge. The cheapest cooling is the heat you never let in, so screening and ventilation come before machinery.
High humidity stalls transpiration, and a crop that cannot transpire cannot take up calcium or shed heat. This is the defining tropical greenhouse problem.
Air handling units condition and distribute air where passive strategies run out, particularly in semi-closed houses and plant factories.
In a well-sealed house, carbon dioxide becomes the limiting factor for photosynthesis long before light does. Enrichment only makes sense once the house holds it.
Bring us the crop, the site, and the goal. We will tell you what a controlled environment can realistically deliver.