Favourable experiences with air control unit

Gepubliceerd op
2 september 2013

Arcadia is a company growing chrysanthemums in Kwintsheul, that has equipped one of its departments with an air control unit. The purpose of this trial is to investigate to what extent the greenhouse climate controla can be improved and energy can be saved.

Wageningen UR greenhouse horticulture accompanies this survey commissioned by the program Greenhouse as an Energy Source.

After almost a year since the start of the research, the following experiences can be mentioned:

  • With a maximum air flow of 5 m3/m2.h the humidity can be controlled very well. During the night the RH-graphs often show a straight line of 85% or 88%.
  • By experiencing that humidity can be controlled that well, one tends more and more to set the humidity sharper. In this way, the RH is now sometimes set at 92%.
  • A lower humidity in combination with a lower temperature in the test department has led to a faster flowering and a higher stem weight. The feared light loss from the tubes has therefore not effected into loss of production.
  • One tube per 28,80 metres gives a satisfying air distribution in the department. Near the air control unit adjustments are necessary to improve the air movement in the corners of the trial department.
  • Up till now, the energy consumption in the trial department was not much lower than in the reference department. After adding an additional screen to the trial department, it is expected that the intended energy saving will be achieved. Also more energy can be saved by choosing a sharper air humidity setpoint.
  • In the summer period it is possible to use the system for cooling the greenhouse air under a closed black-out screen by blowing outside air in.

In addition to Wageningen UR, the trial is consulted by DLV-Plant, Bode/Technokas, Deliflor and three growers. Further, the national commission of chrysanthemum growers has shown their interest.