+PreVENT. Positive pressure system for ecological greenhouses

Novagric promotes a comprehensive geo-ventilation solution, using the soil as a heat exchanger, to achieve dynamic and energy-efficient greenhouse climate control, while maintaining continuous positive pressure as the main ecological tool for pest control.  

Problems of organic farming

The consumption of organic products in European markets has been growing steadily in recent years. Spain is a leader in organic agriculture in Europe, with more than 3,000 hectares of organic greenhouses. Organic agriculture is based on techniques that do not include the use of fertilizers or pesticides, so the use of greenhouses is the only option to have vegetables all year round. However, pest control in organic farming has limitations. In some seasons, insect attacks can lead to a significant decrease in productivity and crop cycle length. Therefore, it is necessary to implement a multi-tunnel greenhouse model that has a high level of hermeticity. This system is intended to maximize the tightness of the greenhouse and optimize the interior climate control by using soil-air heat exchangers to avoid stress situations that favor the appearance of phytosanitary problems and reduce the high energy demand of organic agriculture.  

Project objectives

• Positive pressure system that keeps the greenhouse air volume pressurized, preventing insects from entering the interior, as an ecological strategy in the fight against pests.
• Design of a geo-ventilation model using the ground as a heat exchanger, achieving an active and low energy consumption air conditioning.
• Numerical simulation of the internal flow, and balance of inlets and outlets, using computational fluid mechanics (CFD), introducing all complex thermal effects and providing the field of velocities, pressure, temperature and humidity at all points.
• Greenhouse sizing using fluid mechanics to optimize the scope of the air conditioning system.
• Study of the heat exchange capacity of the soil, soil types, depth, conductivity and the influence of the geographical area and time of year.

 

Project collaborators

• Novagric (Novedades agrícolas, S.A.)
• Polytechnic University of Cartagena