Climate control system and method for a greenhouse

Abstract

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.

Description

FIELD OF THE INVENTION[0001]This invention relates generally to horticulture, and, more particularly, to a greenhouse with a controlled climate, including temperature, humidity and carbon dioxide concentration.BACKGROUND[0002]Commercial greenhouses are high tech production facilities for vegetables and flowers. Heretofore, such greenhouses have been adapted for use in regions with cold winters and arid summers. In such climates, the greenhouse interior may be heated in winter months such as by using boilers, heat pumps, or heat transferred from hot engine exhaust. Such greenhouses may be cooled during hot summer months through evaporative cooling systems. One example of such a cooling system is a pad and fan, which draws dry outside air through a wet porous pad to cool the air via evaporative cooling. To work, the fan must continuously draw ambient air through the pad and exhaust the cooled air to the outside. Fogging and misting systems are also widely used to cool greenhouses in a...

AI Technical Summary

Benefits of technology

This patent describes a greenhouse system that maintains a healthy environment for plant growth. The system utilizes a urea and selective catalytic reduction system to reduce pollutants in exhaust gases, direct heat double effect absorption chillers for efficient heating and cooling, and a mixing and blending unit for controlling the intake of outside air. The system also includes ductwork and a fan and coil unit to provide both cooling and dehumidification. The technical effects of this system include improved air quality and a stable greenhouse environment for plant growth.

Problems solved by technology

Thus, in hot humid climates, the evaporative cooling effect is typically insufficient to maintain a greenhouse at a temperature favorable to plant growth.

In greenhouses with fan and pad evaporative cooling systems, it is difficult to maintain an elevated CO2 concentration, notwithstanding enrichment efforts.

This attenuates any benefit to photosynthesis while increasing production costs and compromising the outside environment.

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