Strawberry grower Eubo Swiss and Grutec Fibre have established a joint venture for mutual operating of the existing 7500 m2 glasshouse. Eubo Swiss will continue to manage production, including rotation of crops, drip irrigation, pollination and harvesting. Grutec Fibre on the other hand is in charge of supplying proper air conditions like temperature and humidity with prevention of condensation, frost and snow damage. It also delivers its newly developed organic soil substrates, providing lifetime plant nutrients, and ahead of every growing season sterilizes the house interior with a residue-free ozone treatment, generated in-situ. Another part of the agreement is that Grutec Fibre collects and sanitizes rain water for the original drip installation.

This joint venture enables both companies to focus on their proven expertise to achieve the best production results without having to buy fossil energy or pest chemicals. Grutec Fibre will apply its latent solar energy storage technique, which heats and cools the house with filtered and moisture conditioned air. "As a result, standard fungus or insect interventions are not required, since a sterile, low moisture climate and sanitized soil substrates are provided", they explain. 

The project is divided into three phases. In the first phase, day-night temperature and moisture harmonization is realized. During a sunny day, heat is latently stored and released in the night, thus elevating low temperatures as well as minimizing peak humidity. In the second phase, the time of heat storage and discharge is prolonged to one or more weeks due to accordingly large energy storage volumes. And in the third phase, cold air from patented Swing Adsorption Cooling limits maximum peak temperatures without shading means, enabling highest natural photosynthesis.

"Having a sun collector area of 800 m2, placed within a bordering PE tunnel, the latent heat storage capacity will be the equivalent of 1500 kg heating oil", Grutec Fibre adds. "To fill the storage completely, roughly four sunny days are required. Collected energy is either set free the next night or over a period of several cold days, depending on demand. Also, recharging happens as soon as the sun shines, independent of the actual storage level. Based on an 8-month grow season and 900 hours of sunshine, up to 30* tons of heating oil can be substituted with the applied technology." (0.5KW/m2 solar power)

All energy is delivered by soft laminar cross flow air-streams at the long site of the greenhouse, minimizing temperature differences within the house. Eubo Swiss expects not only to eliminate fungus and insect threats, but also sees enforced plant growth due to optimized transpiration and its associated metabolism by maximum photosynthesis. However, on the very end, the outsourced climate and sanitizing tasks will relieve the grower not only of stressful weather monitoring and its costly consequences when failing, but also from logistic challenges with substrate preparation as well as from fertilizing efforts since all nutrients are furnished from the soil substrate.

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