UNEX devotes special attention to greenhouse crop cultivation because this technology makes crop farming possible in low-yield regions. In cooperation with our partner, DEBETS SCHALKE, the UNEX Group, operating as the general contractor under EPCM, realizes investment projects on the construction of 5th generation greenhouses complexes all over the globe under the Wessens brand.
85% of the production of the processes and equipment employed is localized in China.
When implementing the Wessens technology, we focus on eco-friendly processes aimed at the protection of the environment by reducing harmful emissions as well as on the development and implementation of zero-waste and low-waste resource-conscious production technologies.
A 5th generation greenhouse complex that is based on an automated hydroponic nutrient delivery system and employs a system that controls and monitors plants throughout their life (scouting and post-scouting) is intended for year-round crop cultivation with a minimum ambient risk factor.
Fifth-generation Wessens greenhouses, or the so-called “semi-enclosed greenhouses”, retain all the advantages of 4th generation greenhouses while heavily exceeding them in several parameters. The advanced techniques employed in 5th generation greenhouses are based on the concepts of intensive vegetable production that involve widespread automation of production processes. These improve the effectiveness of the greenhouse and result in decreased energy and labor costs, and thus product prime costs, and increased general project profitability.
Low-volume techniques
We employ low-volume vegetable crop growing techniques. The Wessens technology is based on the vertical arrangement of crop cultivation which makes it possible to recycle up to 98% of irrigation water.
High process automation
Plants are cultivated using artificial substrates, coconut flake or rock wool mats, using computer-controlled drip feed systems. This enables complete automation of irrigation processes and provides plants with all the necessary nutrients in required quantities and exact proportions depending on the stage of their development.
Fito-monitoring
We employ fito-monitoring, a unique computer-assisted technology that enables uninterrupted automated adjustment of environmental parameters and comprehensive diagnostics of plant conditions as well as direct and continuous monitoring of plant growth and development process.
The technology involves the use of drones that scan plants over the whole cultivation area and transmit collected data to the fito-monitoring system. To analyze and process the data, we use specialized algorithms developed by UNEX Group specialists. Thanks to the balanced approach, the duration of crop vegetation is extended and plants do not accumulate nitrates. This improves product quality substantially.
Artificial supplementary lighting
Supplementary lighting is an important prerequisite of protected crop cultivation. We have switched over to using LED lamps of various light intensity which depends on the cultivated culture and plant development stage, to improve the yield of vegetables by up to 40%.
Ideal environment
During the winter and spring seasons, greenhouse vents are opened to prevent overheating, the same as in less sophisticated greenhouses. However, our systems have 90% fewer vents than conventional greenhouses, whereas these vents are intended only to relieve the slight excess pressure which develops in Wessens greenhouses. It should be pointed out that the air always moves outwards in our greenhouses, so a thermal shock is prevented. And, since there are only a few vents, less heat is wasted. Our greenhouses are capable of cooling themselves during the summer season. All along the greenhouses there are heat-insulating panels that are wetted by water. This water carries away thermal energy when it evaporates, and the air thus cooled is conveyed into the greenhouse.
Heating cost reduction
This is achieved by partially recovering heat energy. In a conventional greenhouse, warm air rises from heating pipes upwards and exits the roof through glazing. The larger the temperature gradient of the inside and outside air, the higher the transpiration intensity. Heat consumption is, naturally, at its maximum during the winter season. In Wessens greenhouses, the air rising to the roof is drawn away by fans and is delivered through plastic hoses to warm cultivation beds. The effect is especially pronounced in systems that use photoculture techniques. In a conventional greenhouse, heat generated by lamps, which amounts to about 90% of the lamp's output, is lost beyond recovery. In a Wessens greenhouse, on the other hand, maximal use of it is made.
The greenhouse is protected from pest invasion
One excellent feature of a Wessens greenhouse is that it generates certain excess pressure. When vents or entry portals are open, insects are unable to overcome the excess pressure and cannot find their way into the greenhouse.
Film tubes located underneath each bed prevent air stagnation in a Wessens greenhouse which mitigates the development of blights.
The system of drainage water collection and disinfection reduces water consumption and toxin release
One of the energy-saving activities that are part of our technology is the introduction of advanced drainage water collection and disinfection equipment. This makes it possible to reduce the volume of water consumed by circulating it repeatedly in the system. Water recycling abates the severity of economy- and environment-related problems by 25%, reduces labor expenditures related to nutrient solution preparation and decreases the amount of toxic waste emissions.
Screening (curtain) system
To save energy, the greenhouse also features a screening system that uses heat- and light-reflecting curtains. Screening enables adjustment of environment parameters: intensity of illumination, temperature and humidity. Besides, it serves to save heat energy by mitigating heat loss by 43 to 75% depending on the type of material used as the curtain sheet. This helps to reduce heating costs by 20%.
CO2 enrichment
Our greenhouses are capable of maintaining the optimal level of CO2 at all times. Equipment that supplies greenhouses not smoke but purified food-grade carbon dioxide gas is considered the most effective and environmentally friendly. Our systems involve the installation of special equipment which automatically supplies CO2 and maintains its content at greenhouse facilities. This makes CO2 dosing possible, improves yield and reduces product cost. Thanks to CO2 fertilization, plants grow faster and have yield improved by up to 40%.
Biological pest control techniques
To protect crops from diseases and pests, our technology mainly employs biological techniques, i.e., useful insects that hunt pests. This technique considerably improves the environmental sustainability of production and permits the producer to put the “BIO” label on its products which enhances product appeal.
Apart from the above major advantages, we use many more contributory techniques that collectively have a synergetic effect resulting in enhanced efficiency of the greenhouse.