Blog Horticulture Tip: Optimizing greenhouse climate with vent control in Priva Connext and Compact CC
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Tip: Optimizing greenhouse climate with vent control in Priva Connext and Compact CC

Priva consultant Hein Jasperse shares tips on how to optimize the greenhouse climate with the vent control in your Priva climate computer.
09 September 2024

As the seasons change, so do the weather conditions. In the Netherlands, for example, late summer (August, September) sees higher temperatures, higher humidity and less wind. There is therefore little difference between the greenhouse temperature and the outdoor temperature and between humidity levels inside and outside the greenhouse at this time of year. To optimize the greenhouse climate, you can configure the vent control settings in the Priva Connext climate computer in a certain way. Priva consultant Hein Jasperse explains how this works.

Setting the lagging

“Most growers normally start venting on the lee side followed by the wind side. The ratio between opening the vents on the lee side and wind side is controlled with the setting ‘lagging’. The lee side opens as soon as the greenhouse temperature exceeds the calculated ventilation temperature. With the 'lagging' setting, you set the difference between the ventilation temperature of the lee side and the wind side..wind," says Hein. “Growers often use the morning to activate transpiration in the crop, for which air exchange is needed. They therefore often choose a lower lagging setting in the morning. During the course of the afternoon, a warmer, more humid climate is often required that is more conducive to vigorous growth. A higher lagging setting is suitable for that.”

Configuring in Priva Connext or Compact CC

Hein Jasperse: “The general advice in this case is that you align the lagging setting with the wind speed. When there is a strong wind, I recommend a higher setting: As the wind increases, there is more air exchange on the lee side with the same vent position. The wind side therefore needs to open less to enable sufficient air exchange. If there is not much wind, air exchange is limited. To ensure sufficient air exchange in these conditions, the wind side needs to open more. That can be achieved with a low lagging setting; in other words, a lower ventilation temperature on the wind side.”

“A good starting point is a low (minimum) lagging setting for a wind speed of up to approx. 1.5 m/s. As the wind speed increases, for example up to 6 to 7 m/s, the lagging should be increased or set to maximum, for example 2 or 3," says Hein. "The minimum and maximum lagging settings for each period can be configured in the vent control. The exact values will ultimately depend on your crop and growing strategy. Priva consultants can give you the best advice on this.”