Design, Control, and Performance Aspects of Semi-Closed Greenhouses

Abstract

Several greenhouse energy saving technologies and management strategies have been developed in order to meet the needs for implementation of production systems with low and efficient energy use and low CO2 emissions. Towards this aim, a number of greenhouse concepts that make use of these technologies have been developed and tested, such as the closed greenhouse, the solar greenhouse, the energy-producing greenhouse, and others. The closed or semi-closed greenhouse concept is widely accepted as a concept to achieve the targets for energy saving and low CO2 emissions. A major difference of this concept to a conventional greenhouse is that climate control by window ventilation is partially or completely replaced by systems that treat the air, regulate the air exchange between inside and outside, and in few cases collect and store the excess heat load in order to be reused at a later time. A semi-closed greenhouse allows temperature, humidity, and CO2 concentration to be controlled independently, during heating as well as cooling mode function. Among others, semi-closed greenhouses offer possibilities for better control of greenhouse environment, for increasing water use efficiency by decreasing the evaporation losses via ventilation and for reducing the pesticide use by decreasing the entry of insects and fungal spores in the greenhouse through the ventilation openings. The aim of this review is to focus on the design, control, and performance aspects of semi-closed greenhouse systems which use either (a) an air treatment corridor with evaporative cooling pad connected with an air distribution system with perforated polyethylene tubes or (b) decentralized air treatment units distributed inside the greenhouse. It gives on overview of the principles of the semi-closed greenhouse, the potential energy consumption and the expected savings. Additionally, it gives insight into the climate conditions in relation to the conventional greenhouse, crop growth, water consumption, and pest control.

Assessment of Heating and Cooling Demands of a Glass Greenhouse in Bucharest, Romania

“…The condensed water can be reused as irrigation water, and the water consumption will be furthermore reduced due to decreased evaporation losses via ventilation. The semi-closed operation of the greenhouse also reduces the risk of insect pests and fungal diseases [36]. An additional advantage is that the reduced ventilation leads to a better control of the CO 2 levels in the greenhouse.…”

Analysis of an Evaporative Cooling Pad Connected to an Air Distribution System of Perforated Polyethylene Tubes in a Greenhouse

“…Other benefits of semi-closed greenhouses could be a reduction in water consumption-due to the decreased transfer of water vapor towards the exterior environment via ventilation-and the decreased use of pesticides as a result of limiting the entrance of insects and the transmission of diseases [15]. Among the lines of improvement in the design of semi-closed greenhouses, the reduction in energy consumption in the distribution of air is underlined [16], as well as the development of refrigeration installations in greenhouses that are efficient in different climates, such as those found in continental, Mediterranean, tropical, and desert environments [17].…”

A Hybrid Prediction Model for CatBoost Tomato Transpiration Rate Based on Feature Extraction

“…The transpiration intensity of tomato is closely related to the amount of irrigation, and many studies have found that ETc decreases with decreasing irrigation [2]. Therefore, reasonable irrigation regulation according to changes in the greenhouse environment and crop growth stage is an important means to ensure the growth of greenhouse crops [3]. Among them, the accurate and quick prediction of the transpiration rate (T r ) of greenhouse crops is the key to making irrigation regulation possible.…”