Expansion of hay ventilation for hay drying
A few kilometers from the Hintertux Glacier, an extremely efficient hay drying system is in operation. This system ensures high hay quality and is almost independent of the weather!
Stefan Mader is an organic farmer and entrepreneur! As an entrepreneur, he runs several vacation homes and sports stores in the tourist region. At peak times, he coordinates 38 employees. For him, his organic farm is a source of energy, a retreat and a passion. His organic farm in Hintertux is located at an altitude of around 1500 m.
He produces organic hay milk there, which is collected and processed fresh every day by ErlebnisSennerei Zillertal.
His 13 dairy cows spend the summer together with other livestock on the mountain pasture. Due to the high ingredients (fat and protein), the organic hay milk farm earns 59 euro cents gross per liter of milk (as of August 2018). Stefan has one employee on his farm. He looks after the cows all year round and is on the mountain pasture in summer. In summer, however, haymaking is a matter for the boss. Stefan has now greatly optimized this work.
Back in 2008, a new barn with a hay barn including hay ventilation was built with two hay boxes, each with a capacity of 420 m3. Stefan decided to install a hay ventilation system because in the past capricious weather conditions had repeatedly caused problems and stress during the hay harvest. A roof extraction system for hay ventilation was planned and implemented. In addition, the biomass heating system was integrated as an additional heat source. This was done by placing a hot water heat exchanger in front of the hay drying fan. In practice, however, it turned out that the hot water heat exchanger was overtaxed due to the operating location (glacier, altitude).
As the roof extraction system only provided sufficient heat for drying during the day and only when the weather was fine, Stefan started looking for ways to improve the system and ultimately decided on a LASCO dehumidifier. The newly purchased dehumidifier now enables a 100% circulation system. This means that the air saturated with water is not led outside, but is recycled by the dehumidifier, i.e. dehumidified and reheated. This works very similarly to the functional principle of a heat pump.
The hot water heat exchanger is still in use and heats the air additionally. This results in drying temperatures of up to 38°C. The roof extraction system is now only used on hot and dry summer days. A trick: Stefan uses a PVC process to separate the drying process from the rest of the barn.
This means that the entire building does not have to be heated up. In addition to the dehumidifier, a new hay crane was also purchased. Thanks to the fully glazed cabin and the standard filter system, the exposure to dust in the cabin is reduced by almost 100%. Drying hay is a craft, Stefan Mader is convinced. Even the best technology is ineffective if, for example, the haystack “closes” or air ducts form. He believes that precise feeding and constant haystack monitoring are essential for successful drying. He compensates for the extra work caused by hay drying by saving one turning operation during the hay harvest. He also saves approx. 20% on veterinary costs. Fertility, on the other hand, has increased. The same applies to ingredients such as fat and protein. Stefan can save on concentrated feed!
