Van der Avoird Trayplant has won several awards in recent years. This year, the winner of the Tuinbouw Ondernemersprijs 2023 won the WKO (Thermal heat storage) Sustainability Award 2024. However, forerunners in the sector have many challenges. A group of fellow growers visited the farm on Tuesday 12 November to talk about energy supply for solitary soft fruit farms, and heard from entrepreneur Peter about those challenges too.
Among other things, the visiting growers came to calculate the business case for an air-water heat pump. But there are more energy innovations that growers will need to study now that leaning solely on natural gas is near impossible because of rising energy costs. Peter's advice here: "Look outside your own sector. Everything has already been invented there."
A word on the CHP system
Choice of cooling
Since the winter of 2019-2020, Van der Avoird Trayplant's WKO system has been in operation. Peter is enthusiastic about it, as demonstrated once again on Tuesday. The system is a godsend for the company, which is actually "in the wrong place". By this, the grower means that there is no collective energy supply for greenhouse horticulture companies to connect to, for example. The same applies to many solitary soft fruit farms in North Brabant and Limburg.
The soft fruit growing company decided to invest in a WKO system after first checking what energy technologies other companies use. A WKO system is not new. Peter pointed out to the group of colleagues that the system has been around for about 25 years but it did not break through. Peter noticed that the technology was mainly used in horticulture at the time for very energy-intensive crops, something that soft fruit plant propagation is not. Rather, there is a cooling problem. Today, Van der Avoird Trayplant even has heat to spare. With the high gas prices at the time the company decided to invest in a WKO system, however, the system proved unprofitable. It was soon clear to Peter and his team that with better cooling, the quality of the cuttings could go up, and the failure rate down.
The advantage of a temporarily empty greenhouse: you can see the techniques.
Heat left over
Meanwhile, Peter is amazed at how many megawatts of heat the farm, where they pump water around 24/7, can store in the ground. Incredibly, there is too much heat, at one of the two sites where a CHP system is currently running. The company is exploring options to release that heat into the surrounding area.
Peter explains that the surplus heat arises because the greenhouse in which the system is running is also very well insulated, including a double screen. But it is important to be able to dehumidify properly as well. Peter studied the chrysanthemum industry to find out more about systems. The air hoses he saw there now hang in his greenhouse.
In addition, Caeli fan units are used in the greenhouse columns for maximum dehumidification. With the combination of techniques, the propagator is able to extract 10-12% moisture from the air during the most difficult periods.
New cultivation concepts are tested in the demo greenhouse at Molenschot
Demo cultivation
The group of colleagues visiting Van der Avoird Trayplant also had a chance to take a look at the demo greenhouse on the premises in Molenschot. There, the company is testing new cultivation concepts. In one greenhouse, they propagate, cut, and grow soft fruit such as raspberry plants and strawberry plants.
A striking feature is the blackout screen hanging in the greenhouse. Even more striking is that, unlike in the propagation greenhouse, they grow without a dehumidification system. And yet, Peter assures interested colleagues, that the desired productions are achieved, and there are no moisture problems. Maybe it's because of the high 24-hour temperatures we achieve here, he says. That's possible thanks to the WKO heat. Only at temperatures a few degrees below zero does a gas-fired plant still jump in. "So last winter that was not much needed," he says.
The demo greenhouse, in April 2022
In Molenschot, they cheerfully continue testing. Picking 30 kilograms of strawberries a year, without gas and without using plant protection products, that's where they want to go.
For more information:
Van der Avoird Trayplant
Rimpelaar 3
5124 RB Molenschot, The Netherlands
Tel: +31 (0)161 451 427
[email protected]
www.trayplant.nl