The innovative Airflow system by ErfGoed offers energy savings opportunities and can significantly lower crop temperatures. This benefits crop growth and quality, as demonstrated by recent measurements and experiments conducted with the Airflow system. While the results are positive, and the system shows promise, many questions remain, and further research is necessary.
The new Airflow system consists of an ebb-and-flow floor, which is heated and cooled through hoses beneath the floor. Additionally, air is introduced through the floor's distribution pipes to heat or cool the air around the crop. These pipes have small holes, distributing air through the porous floor. The unique aspect of the system lies mainly in the combination of heating and cooling hoses and the introduction of air.
ErfGoed recently conducted extensive experiments with the new system, mainly at its location in Moerkapelle, focusing on Sarcococca cultivation. Leo de Rijke, an advisor from De Rijke Techniek, played a significant role in conducting various measurements and analyses in these experiments. "We measured both the pot, floor, and room temperature," he explained. "We did this in a section with the innovative floor and a 'normal' section with a standard ebb and flow floor from ErfGoed. Since all other conditions were identical, the added value of the Airflow floor was very clearly visible."
Part of the research involved assessing the effects of heating using the Airflow floor. Low-grade heat at 35 degrees Celsius was introduced through the hoses. Additionally, air was introduced into the floor, which was distributed through the floor using a unique system. "We observed that introducing the air could cool down the low-grade heat to a temperature of 22 degrees. Without the introduction of air, the return temperature was 27 degrees. This means that you can effectively utilize low-grade heat with the AirFlow floor. In other words, the Airflow system provides higher efficiency with low-grade heat. This is because the floor's heat output capacity is increased by introducing air."
According to De Rijke, this finding presents opportunities for energy savings and may be of interest to entrepreneurs working with geothermal heat or heat pump. "We introduced low-grade heat for the experiment through the boiler, but you can also use geothermal heat or heat from a heat pump. As an entrepreneur, you can choose either to cool down the heat as much as possible or to lower the supply temperature. This means you need less energy to maintain the temperature in your garden. The exact amount needs further investigation, but this results in better heat pump or geothermal source efficiency."
In addition, extensive experiments were conducted recently to cool the Airflow floor using the hoses in combination with introducing cold air. The advisor stated that this proved to have a clear advantage on hot days. "We observed that the temperature between the crops in the section with the Airflow system was, on average, about five degrees lower than in the section with the regular ErfGoed floor. This is thanks to the combination of introducing cold water through the hoses and cold air, as well as the precision of delivering cold air where it's needed."
The lower temperature, according to Cor Bremmer, Commercial Director at ErfGoed, offers clear advantages for crop growth. "A temperature between 20 and 30 degrees is optimal for crop growth. Additionally, the relative humidity increased as the dry airflow absorbed moisture from the floor, causing the stomata to open, promoting photosynthesis. Furthermore, the air movement benefits plant growth, and we observed improvements in the microclimate around the plant."
Both heating and cooling with the Airflow system have proven to have significant added value. Which variation is most interesting depends on a grower's specific business situation and the location of their facility, according to De Rijke. "It's logical that cooling with the Airflow system is probably more interesting for entrepreneurs in warmer regions.
However, these are aspects that we will further investigate in follow-up experiments. There are still many questions, such as whether the investment in the system is cost-effective and, if so, over what timeframe. But it's clear that the Airflow system has great potential." New experiments will be tested at ErfGoed and onsite with some customers in practical applications.
Want to know more about the Airflow system or are interested in constructing a practical trial on your nursery? Contact ErfGoed at info@erfgoed.com or sign-up for our updates.
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