The weather is getting cooler and autumn is at its end.
This offers the possibility to control the greenhouse climate even more and achieve the desired 24-hour temperature.
The process control computer's 24-hour temperature strategy program can help you automate your control.

Not all users currently employ a 24-hour temperature strategy, but for vegetable and ornamental plant growing, it is a functional module that can really help you reach your production plans and goals more easily.

During the day, it is inevitable that as a grower you will encounter some weather conditions such as light radiation or rain showers. This may cause the greenhouse temperature to deviate from the required 24-hour temperature. In order to be able to achieve the desired 24-hour temperature, it is necessary to compensate for the temperature at other times of the day.

 

Ornamental planting

In ornamental planting, we know that growers want to control the temperature of the cultivation period. The daily temperature largely determines the length of the cultivation period. With the 24-hour temperature strategy, it is possible to set the average temperature over a 24-hour period.

The 24-hour temperature strategy screen in the FarmGeeker Process Control PC operating software allows you to set the temperature range that can be compensated for each cycle of the control. After a temperature deviation occurs, this control will automatically distribute compensation across the full range of time remaining in the 24-hour cycle. For example, if there are 5 hours left in the 24 hour cycle and there is a 1 degree deviation from the 24 hour temperature setting, then 0.2 degrees will be compensated for each of the next hours. Martin van der Mei, consultant for gerbera growers, agrees with the benefits of this mechanism.

"This control procedure is widely used on numerous gerbera farms. Almost all gerbera growers have a PAR (photosynthetically active radiation) meter. The consulting firm Flori Consult Group has developed a table for gerbera chrysanthemum growing from which it is possible to find the optimum 24-hour temperature corresponding to a certain sum of PAR and the daily CO2 value. In this way, gerbera growers learn how to keep the crop state in balance."

The figure below illustrates how the 24-hour temperature strategy works. In the case of a gerbera grower, for example, the 24-hour temperature strategy depends on the amount of light radiation accumulated. As you can clearly see in the graph, the higher the light radiation accumulation, the higher the calculated 24-hour temperature. The next day is a more sunny day, so the light radiation accumulation value is higher.

The 24-hour cycle starts at 6:00 am. It can be clearly seen that the actual 24-hour temperature (light green line) overlaps with the calculated 24-hour temperature (dark blue line) at the end of the 24-hour cycle.

The red and light blue lines are the corrections made by the 24-hour temperature control program for heating and ventilation temperatures. These parameters are adjusted to ensure that the calculated 24-hour average temperature is reached at the end of the 24-hour cycle.

 

Vegetable farming

Vegetable growers have a different focus. For vegetables, it is not the fixed cultivation period that is important, but the speed of fruit development as much as possible. If light is strong and the crop will produce more sugar, then the 24-hour temperature can be higher to speed up the development of the crop and thus produce new fruit.

The 24-hour temperature can be determined by the amount of light radiation accumulated. If more light radiation is accumulated, the temperature inside the greenhouse as well as the 24-hour temperature will rise automatically. Depending on the actual daily temperature, temperature compensation can be done at night to finally achieve the daily required temperature.

When you apply a 24-hour temperature policy, the process control computer automatically compensates for the default settings for heating and ventilation. You do not need to change them manually.

Advantages

A major advantage of the 24-hour temperature strategy is that you can control the 24-hour average temperature more precisely according to the needs of your crop, making it easier for you to cope with changing weather conditions.

Especially for ornamentals, it makes planting plans more precise and easy to achieve.

For vegetable growing, the module can help to achieve maximum yields. The accumulated amount of light radiation is the basis.

The 24-hour temperature strategy also provides indirect energy savings. For example, in spring, when daytime temperatures are still cold, the module makes it simpler and more economical to control temperature compensation at night by unfolding the curtain to keep more heat in the greenhouse.

For example, in cases where the maximum water temperature in the heating pipes is limited and undesirable outdoor climatic conditions combine to cause the demand temperature to not be reached in the greenhouse during the day, the temperature can be automatically adjusted to the demand temperature at night through a 24-hour temperature strategy controlled by an energy curtain that unfolds for insulation.

Unique control module

The 24-hour temperature strategy is unique to FarmGeeker. The control module fully and automatically controls ventilation and heating temperatures to achieve 24-hour temperatures. If the heating is continuous, the ventilation temperature will rise in parallel. If the calculated heating temperature decreases, the ventilation temperature may then decrease or remain the same. If required, the temperature difference between curtain unfolding and closing can also be correlated with the heating temperature and thus indirectly controlled.

If you want to use a 24-hour temperature strategy, it is important to correlate heating, ventilation and a 24-hour temperature strategy.

Your FarmGeeker consultant can help you create a dedicated page in FarmGeeker Air Control that gives you an overview of all relevant information through one interface.