{"id":14888,"date":"2021-04-06T08:28:24","date_gmt":"2021-04-06T06:28:24","guid":{"rendered":"https:\/\/mag.ebmpapst.com\/en\/?p=14888"},"modified":"2025-11-11T14:33:05","modified_gmt":"2025-11-11T13:33:05","slug":"greenhouses-air-supply-distribution-efficient-solution-ebm-papst","status":"publish","type":"post","link":"https:\/\/mag.ebmpapst.com\/en\/industries\/refrigeration-ventilation\/greenhouses-air-supply-distribution-efficient-solution-ebm-papst_14888\/","title":{"rendered":"Good climate for top crops"},"content":{"rendered":"

Super\u00admar\u00adkets have not sold by the season for a long time. Fresh and crispy toma\u00adtoes, peppers, and other produce are avail\u00adable in the produce section throughout the year, regard\u00adless of the season. By providing summery condi\u00adtions during the winter, green\u00adhouses are one of the things making this possible (Fig. 1). The situ\u00ada\u00adtion has bene\u00adfits for both consumers and farmers. The latter can use green\u00adhouses to harvest more crops and mini\u00admize risk in the process: under a protec\u00adtive roof, weather-related crop fail\u00adures and hail damage are not an issue. In prin\u00adciple, with smart irri\u00adga\u00adtion systems and air condi\u00adtioners, plants can even thrive in places where nature would not normally allow it, such as deserts or cold regions.<\/p>\n

A ques\u00adtion of distri\u00adb\u00adu\u00adtion<\/h2>\n

Unfor\u00adtu\u00adnately, cold or hot spots may arise over the entire green\u00adhouse area. Only limited plant growth is possible in such places, and the plants are more suscep\u00adtible to disease there. Photo\u00adsyn\u00adthesis and plant growth are strongly depen\u00addent on the temper\u00ada\u00adture. If it is too cold, photo\u00adsyn\u00adthesis proceeds very slowly; if it is too warm, it comes to a stop very quickly.<\/p>\n

AxiCool fans from ebm-papst enable precise control of the air flow.<\/p><\/blockquote>\n

On the one hand, the optimum temper\u00ada\u00adture that needs to be evenly distrib\u00aduted throughout the green\u00adhouse depends on the type of plant. And on the other hand, a good supply of fresh air and air circu\u00adla\u00adtion are the keys to a good harvest \u2013 along\u00adside the right temper\u00ada\u00adture and humidity. This is why the goal is to create uniform climatic condi\u00adtions with a roaming air flow by evenly distrib\u00aduting the air at a constant speed over the entire green\u00adhouse.<\/p>\n

Hori\u00adzontal venti\u00adlation is a common method of evenly distrib\u00aduting the air in green\u00adhouses (Fig. 2). In this method, the air is guided above the plants in the hori\u00adzontal direc\u00adtion. As a rule, fresh air is supplied through the sides of the green\u00adhouse. A highly inno\u00adv\u00ada\u00adtive air supply method is the use of venti\u00adlation tubes from below (Fig. 3). This process ensures that suffi\u00adcient CO2<\/sub> reaches the plants. This is partic\u00adu\u00adlarly impor\u00adtant since CO2<\/sub> is the base substance for photo\u00adsyn\u00adthesis in plants.<\/p>\n

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Figure 2: With hori\u00adzontal venti\u00adlation, the air in the green\u00adhouse is circu\u00adlated so as to ensure a uniform temper\u00ada\u00adture around the plants. (Graphic | ebm-papst)<\/p><\/div>\n

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Figure 3: With venti\u00adlation tubes, the air is supplied under\u00adneath the plants, providing an optimum supply of CO2<\/sub> to the under\u00adsides of their leaves. (Graphic | ebm-papst)<\/p><\/div>\n<\/div>\n

Solu\u00adtion from refrig\u00ader\u00ada\u00adtion tech\u00adnology<\/h2>\n

Green\u00adhouse oper\u00ada\u00adtors have the option to use a venti\u00adlation system that meets all of the plants\u2019 needs and is also easy to install. The solu\u00adtion uses AxiCool axial fans from ebm-papst (Fig. 4).<\/p>\n

Figure 4: AxiCool fans with guide vanes on the outlet side are used for hori\u00adzontal venti\u00adlation. They have a white housing to reflect as much of the inci\u00addent light (impor\u00adtant for plant growth) as possible. (Photo | ebm-papst)<\/p><\/div><\/div>\n

They were orig\u00adi\u00adnally devel\u00adoped for refrig\u00ader\u00ada\u00adtion tech\u00adnology since even temper\u00ada\u00adture distri\u00adb\u00adu\u00adtion is also impor\u00adtant to keep goods fresh in cold storage rooms. That also makes them ideal for green\u00adhouses. They feature high air throw and enable precise control of the air flow.<\/p>\n

Guide vanes are also installed on the outlet side of AxiCool fans to improve overall effi\u00adciency (Fig. 5). The housing and mounting are white in order to reflect as much inci\u00addent sunlight from the green\u00adhouse as possible. To meet the service life require\u00adments, the fans are specially equipped for use in the high humidity of green\u00adhouses, and their plastic compo\u00adnents are made of UV-resis\u00adtant mate\u00adrials that are also easy to clean. With their aero\u00addy\u00adnamic blade design, axial fans also run very quietly \u2013 a major improve\u00adment in working condi\u00adtions for the employees.<\/p>\n

ebm-papst Inc. in Farm\u00adington, U.S.A. devel\u00adoped a height-adjustable mounting system for the AxiCool fans that is easy to install. It allows the fan posi\u00adtion to be adjusted to the plant height, which changes as the plants grow. This adds up to a customized, high-power air guiding system that opti\u00admally simu\u00adlates the natural move\u00adment of air.<\/p>\n

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Figure 5: Air flow for AxiCool without guide vanes ... <\/p><\/div>\n

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... Opti\u00admized air flow with guide vanes, doubling the air throw. (Graphic | ebm-papst)<\/p><\/div>\n<\/div>\n

Inno\u00adv\u00ada\u00adtive: Air supply from below<\/h2>\n

Energy-effi\u00adcient back\u00adward-curved centrifugal fans or espe\u00adcially high-pres\u00adsure axial fans from ebm-papst are used for the tube venti\u00adlation system (Fig. 6). The air is supplied through a perfo\u00adrated tube installed under the plants. The axial fans intake air that has usually been condi\u00adtioned (temper\u00ada\u00adture-controlled and humidified\/dehumidified) from the air treat\u00adment chamber of \u201csemi-closed\u201d green\u00adhouses.<\/p>\n

The air is first pressed into the tube, flows upward through holes past the plants, and is then guided back into the intake air flow. The result is a defined circuit of air flow. With this type of air supply, the under\u00adsides of the leaves are opti\u00admally supplied with CO2<\/sub>. This is espe\u00adcially effi\u00adcient, since that is where the intake for photo\u00adsyn\u00adthesis occurs. Thanks to the high-powered fans, espe\u00adcially long tubes can be used. Such systems enable the imple\u00admen\u00adta\u00adtion of effi\u00adcient venti\u00adlation solu\u00adtions for maximum yield in large-scale green\u00adhouse instal\u00adla\u00adtions such as those in the United States and also in Euro\u00adpean coun\u00adtries such as Spain and the Nether\u00adlands.<\/p>\n

Figure 6: High-pres\u00adsure axial fans for tube venti\u00adlation that supplies the plants with CO2 from below. (Photo | ebm-papst)<\/p><\/div><\/div>\n

Energy saving made easy<\/h2>\n

It is also impor\u00adtant to have energy-saving EC motors drive the fans. These grid-fed, perma\u00adnently ener\u00adgized, synchro\u00adnous motors with elec\u00adtronic commu\u00adta\u00adtion, also called BLDC (brush\u00adless DC) motors, boast effi\u00adcien\u00adcies that are far above effi\u00adciency class IE4. An inno\u00adv\u00ada\u00adtive green\u00adhouse design in Canada uses ebm-papst AxiCool fans and its elec\u00adtricity bills were reduced by more than 70% in compar\u00adison to the venti\u00adlation tech\u00adnology previ\u00adously used.<\/p>\n

EC motors have another advan\u00adtage: their control char\u00adac\u00adter\u00adis\u00adtics. They can be controlled across the entire speed range while retaining their high effi\u00adciency in partial-load oper\u00ada\u00adtion. This means that fans on smooth walls can be set to a higher speed than fans on walls with protru\u00adsions or obsta\u00adcles. Air flow effec\u00adtive\u00adness can be opti\u00admized with this precise tuning. Digital MODBUS-RTU, which use the 4\u201320 mA or 0\u201310\u2008V inter\u00adface, can be used to control the fans as needed. The MODBUS commu\u00adni\u00adca\u00adtion inter\u00adface can be used to configure and monitor the fans according to the situ\u00ada\u00adtion in the green\u00adhouse with utmost preci\u00adsion.<\/p>\n

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Ideal air solu\u00adtion<\/h3>\n
    \n
  • Air supply and mixing are impor\u00adtant factors for plant growth and can be precisely controlled with axial fans from ebm-papst. Their most impor\u00adtant advan\u00adtages:<\/li>\n
  • UV-resis\u00adtant white housing for maximum light reflec\u00adtion<\/li>\n
  • Space-saving config\u00adu\u00adra\u00adtion for limited shading<\/li>\n
  • Energy-effi\u00adcient, main\u00adte\u00adnance-free EC motors<\/li>\n
  • Espe\u00adcially quiet oper\u00ada\u00adtion<\/li>\n
  • Fan system with on-board elec\u00adtronics for easy plug & play startup<\/li>\n
  • Speed control as needed via MODBUS-RTU, 4\u201320 mA or 0\u201310 V<\/li>\n<\/ul>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

    Super\u00admar\u00adkets have not sold by the season for a long time. Fresh and crispy toma\u00adtoes, peppers, and other produce are avail\u00adable in the produce section throughout the year, regard\u00adless of the season. By providing summery condi\u00adtions during the winter, green\u00adhouses are one of the things making this possible (Fig. 1). The situ\u00ada\u00adtion has bene\u00adfits for [\u2026]<\/p>\n","protected":false},"author":12,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"wp_typography_post_enhancements_disabled":false,"footnotes":""},"categories":[16,9],"tags":[],"class_list":["post-14888","post","type-post","status-publish","format-standard","hentry","category-fans","category-refrigeration-ventilation"],"acf":[],"_links":{"self":[{"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/posts\/14888","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/users\/12"}],"replies":[{"embeddable":true,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/comments?post=14888"}],"version-history":[{"count":9,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/posts\/14888\/revisions"}],"predecessor-version":[{"id":22292,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/posts\/14888\/revisions\/22292"}],"wp:attachment":[{"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/media?parent=14888"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/categories?post=14888"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/tags?post=14888"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}