With systems based on air handling to make an optimal glasshouse climate , Van Dijk heating plant seemed to be ahead of the game for a farsighted metre . The gas price was low and so was the importunity to think about alternative arrangement for greenhouse heating . The energy crisis is changing all that . At their head spot in Bunnik , the Netherlands , they have remark , although they are not overjoyed .
" you could see at it in two ways , " says Sales Manager Joek van der Zeeuw . " At current petrol price , the payback period for an investment in our Active Ventilation System ( AVS ) is substantially shorter than before . That is convinced . However , growers do require to have money left in their pocket to invest . With the current gas prices , that is a cause for concern . "
Hans Harting and Joek van der Zeeuw , the regular faces for Van Dijk Heating at horticultural fair
statute law and innovationJoek notes that it is ' human nature ' to only start improving when the force per unit area is high . " That is pass off now . Even though you always have pioneer who take sure footstep earlier , the mass usually stick to later . In the past times , you could see that when growers switched to CHPs , for model . When it turned out that there was money to be made , many did the substitution at the end of the 90s . initiation and looking ahead are extremely important to us . For example , we have our own R&D department . late development mean that in the near futurity we will be make for full of focus on both greenhouse climate systems and a sodium remover . In the latter case , we are counter legislation that will take this . Legislation in the Netherlands is often the flushed tape that sets innovations in motion , apart from the innovativeness of growers , of course . They certainly should n’t be underestimate . "
Gas - free cultivationVan Dijk heat has already gained experience in the food market with the various AVS system in late years . The AVS systems are useable in various versions : in addition to a regular version , there is also one with heat recovery and one with an extra cool auction block . Since 2019 , the AVS system has been tested in KAS2030 at Wageningen University & Research . Researchers are anticipating gaseous state - free cultivation and are acquit trials there with potanthurium , gerbera , freesia , and strawberry . Joek : " It was noticed that gas - free cultivation function better with crop that evaporate well . Potanthurium does not . If it is humid in the greenhouse , condensation quickly form on the façade . You then ask to adjust the humidity in the craw . We provide that result with air intervention in the shape of various AVS system . "
Stable basic capacityJoek does a bunch of external work for Van Dijk heating . He knows the necessary examples of projects where agriculturalist opt for AVS system . " A grower in New Zealand did not view strain treatment for a long time , but when it turned out that the government might not guarantee throttle , alternatives were considered . " The heat ticker came into the movie . " But for those few week with blossom power , that ’s a serious investing for the grower , and for only a few weeks . " adjust the crop to bump off that blossom power is another option . " By grow with a stable introductory capacity , the investments in the applied science are different . Year - turn zephyr treatment also benefits the lineament of the crop . "
CO2 needed at little marginsAbroad , CO2 is often not taken into consideration when clear option , Joek take note . " The margins are high there . If a grower has to choose between the mellow costs of constructing a gas pipeline ( with which the grower can also farm CO2 when heat ) or a few hebdomad of slightly down yield without CO2 , the pick often falls on the latter . They are then prepared to accept a somewhat lower production without CO2 .
AVS organisation at agriculturist Seasun in Kapelle , the Netherlands
AnticipateThis is not possible in the Netherlands , Joek knows . " Here , CO2 is required in cultivation to calculate margin up to four denary place . Without CO2 , and therefore a lower yield , many growers will not survive . It makes the whole step to gas - liberal culture without CHP and therefore CO2 product much more hard . " He does cognize growers who have already done it . " In Kapelle in 2018 , Seasun had 1/3 of its new 13 - hectare construction equipped with an AVS organization with warmth recovery . They wanted to respond to all - galvanising cultivation and are now gaining experience with this . Experience that will add up in handy in the time to come when gas - free cultivation becomes a realness , while in the meantime aviation handling also meliorate the quality of your intersection . "
throttle - barren cultivation is often not yet a reality . Joek realise alternative to gas , include hydrogen , but immediately notes that H is not the response . " Combustion does not produce CO2 . agriculturist here in the Netherlands urgently demand that CO2 . "
integrating of AVS in existing greenhouseAnother example shows that the investment funds in an AVS system does not necessarily have to be made so as to achieve ' gas - free ' cultivation . In this causa , an example from Norway . After switching one of his greenhouses from HPS to moderate lighting , a cucumber agriculturalist there opted for an AVS organisation with heat recovery . " This grower saw electricity becoming more and more expensive , but then lack the radiant rut of HPS when growing under LED . By using line treatment with heat recovery , the raiser now brings in that high temperature and saves on energy consumption at the same time . "
For a second greenhouse , the same grower is looking for a unlike result . " That greenhouse is closer to the boiler house . It still has HPS . The grower is considering harvesting energy here with a heat pump . It shows that even for each grower there are often several options . Moreover , this example can easy be compared with growers in the Netherlands , also because it is a agriculturist who is adapting his live nursery . I expect the latter to happen in the Netherlands in the next few years because of the high energy prices . "
Many perspective on climateFor Joek and his colleagues , it is authoritative to spar with growers as much as possible to chance out what the falter occlusion are . " I am a techie . I know glasshouse horticulture , but I can always learn a lot from agriculturist . Besides , I cogitate there are more linear perspective on the climate than there are growers . He mention another model . " I once visited a grower in dark and cloudy weather . It was insensate in the greenhouse . I can always wear out a T - shirt in the greenhouse , it is usually warm enough there . This was not possible on this occasion , because , the raiser argued , in inhuman and sorry conditions ' the plant does n’t do anything anyway ' , so there was little point in put in much extra energy . "
Air movementCreating gentle wind cause in the greenhouse is something they strongly consider in at Van Dijk heating . " you may accomplish this air social movement in various ways using different technique , but we powerfully believe in grow under overpressure . Unlike go air to and from the nursery wall , as materialize with ventilator , you get a very even climate with this . We push quick air outdoors . This signify you wo n’t see a cold fall through a golf hole in the projection screen , as sometimes happens . What ’s more , with a unopen filmdom , without radiation , and with overpressure , the temperature distribution in the entire glasshouse is more even . As a result , the temperature divergence in the glasshouse is 1 grade Celsius with , moreover , a gain in caliber for your product . If free energy is not already a reasonableness to make investments , then there is always the caliber . "
AVS system in chrysanthemum cultivation , seen here in a greenhouse at Delphy
InnovationNow it is a casing of waiting to see what the energy crisis does , Joek notes . " Fortunately , innovation does not stand still . On the contrary . In the chrysanthemum sector , we are meddlesome upgrade our air handling units to a very high capacity for multilayer cultivation in clipping yield . From 700 cubic m we are going to 1300 cubic beat for this project , with the possibility of cool off in the future should this be necessary . "
For more information : Joek van der ZeeuwVan Dijk heating+31 ( 0)30 659 21 58[email protected]www.vandijkheating.com
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