Higher returns at Jef Adriaensen due to imbalance control

Jef Adriaensen’s strawberry business is located in Hoogstraten, not far from the auction. He took over from his parents and is enthusiastically innovating the family greenhouses.

Upon arrival at Jef Adriaensen’s strawberry business, we instantly notice a number of large storage tanks. What’s in them?

‘Our rainwater supply! That last big storage tank is a water treatment plant with a slow sand filter, which allows us to run our entire operation on rainwater. We recover the water that leaks from the planters and send it through the installation for reuse. So our water supply is 95% circular.’
This is Jef Adriaensen, second-generation strawberry grower who is working hard to completely modernise the family greenhouses.

And that requires quite a bit of electricity. Powerful pumps circulate warm water through the glass houses, currently keeping the temperature between 12 and 16 degrees. LED lighting provides optimal lighting to stimulate growth, and the heating system’s flue gases are used to blow extra CO2 into the greenhouse. 

A PV installation on various buildings ensures in-house energy production and is charged in the battery for use during the night. Additional imbalance steering by Yuso provides income that significantly reduces the electricity bill and also makes most months negative. A large hot water buffer is used to recover heat from the gas installation for use at night. 

Jef Adriaensen’s strawberry business is affiliated with a cooperative of farmers that is in turn associated with the Hoogstraten auction. This ensures good collaboration between the different growers.

‘The entire strawberry plantation is 5.5 hectares of greenhouses, of which about 4 hectares are glass and the rest plastic.’ The difference in material ensures phased flowering of the strawberries: the glass cultivation started mid-January with 2.5 hectares of planting and will hopefully yield fruit by 25 March, the cultivation in the plastic greenhouses starts at the end of February and will yield fruit by the beginning of May. 

In this way, Jef can correctly manage all greenhouses with one permanent team.

Are the strawberries sprayed a lot? ‘Minimally,’ Jef replies. ‘We use biological repellents to combat bugs: the good bugs fight the bad bugs. We now also work organically for fungal control. Last year we invested in a UV radiation device for that purpose. It’s used at night to irradiate the plants with UV light. Spraying is only done for plant rot, and that happens at least once every 10 days. This leaves an absolute minimum of residue on the plants, in the soil and in the water. Pesticide residue on strawberries is strictly controlled, so Belgian strawberries are minimally sprayed, says Jef. ‘It’s also time-consuming: I spend at least two hours spraying the plants in one greenhouse. So the less the better.’

The strawberries are grown in plastic trays that are used again and again. ‘We used to use plastic bags with soil, but that created a lot of plastic waste. So we switched to plastic trays. The soil is replaced after each crop, and we compost the used soil.’

And so Jef Adriaensen’s Belgian strawberry farm is a story of continuous innovation, which Yuso and Ecotechnics are proud to be part of. Ecotechnics installed the PV system here and halfway through 2024 also the battery, which is used both for self-consumption and for imbalance steering. As a result, energy is purchased at a minimum cost price and excess energy from the PV system is sold efficiently on the imbalance market.

Explanation of the screenshot from Yuso Inside:

These are the yields from the injection of solar energy from the battery. All the yellow bars correspond to injection yields from imbalance, all the blue bars are injection yields without imbalance control (self-supply mode). It is clear to see that the main source of income is imbalance steering. Revenues from self-consumption are smaller due to the limited price differences in the Day Ahead market price.