The new Tolsma-Grisnich mechanical cooling system in Peter Holster’s storage facility faced a challenge from the start: it had to work smoothly together with his existing cooling system, which is from a different manufacturer. After almost a full season of cooling experience, the seed potato grower is very satisfied. “It’s exactly what I was looking for”
When Peter Holster had a new box storage facility built for his seed potatoes in 2017, he already knew that a new mechanical cooling system would be added later. Connection points for the evaporators and condensation water drains had already been installed in the new building. But when the time came in 2019, there was an unexpected complication. The supplier of his existing storage system had gone bankrupt.
“No matter what, I wanted to be in a position that I could go to one company for everything if anything happened. So not to one company for the control cabinet and the sensors and to a different company for the refrigeration and the storage computer.” After a round of tenders with multiple companies, Holster choose TOLSMA. “I had a good feeling about them,” he explains. “And I was right. I’m really happy with the system they installed.”
On Tolsma’s advice, Holster opted for the Green Cool Unit (GCU) 45 (the number indicates the cooling capacity). Tolsma adviser Paul den Engelsen, also at the interview, explains: “The GCU 45 gives you what we call direct cooling. This type of system is ideally suited for situations with a limited number of cells and no major temperature differences between them. Incidentally, the electic connection value is only around 20% of the cooling capacity. This is down to the high efficiency of the system.”
Den Engelsen believes that the greatest advantage of this system is its simplicity. “They’re modern systems with no frills. Their simplicity makes them cheaper and means they’re easier to install and adjust. They’re very robust systems.” Holster continues: “It’s a kind of ‘plug and play’ system. Of course you have to define your refrigeration strategy yourself, but I was able to use it more or less independently after the first instruction session.”
The Holster cooling system uses a natural refrigerant. In Tolsma’s GCU series, this is propane. “This refrigerant fits perfectly with this direct cooling system and with the changing climate conditions it gives you much more operational reliability than CO2 as a refrigerant,” says Den Engelsen. “You work with low pressure and the system volume is limited. The pipes and welding are very high quality. Our installation work complies with the very latest safety regulations.” Holster sees even more benefits: “Natural refrigerants are more environmentally friendly and cheaper.”
As already mentioned, Holster’s new cooling system had to operate alongside an existing storage system of a different brand. “That made it a pretty unusual assignment,” says Den Engelsen. “But we managed to make it work with relatively few interventions. We only needed to make minor adjustments to be able to reuse the existing temperature sensors. And we had to replace a PLC in the control cabinet for the link with our Vision Control storage computer. But that was all.”