In the beginning
The first drilling for geothermal heat to heat the greenhouses began in 2006. This test drilling gave enough positive feedback to continue with the project.
In total, there are two boreholes at a depth of 1,700 metres and 1,200 metres apart. The temperature of the pumped water from the production well is 60 °C. When reinjected into the sandstone layer via the injection well, it has a temperature between 24 °C and 34 °C. The flow rate of the water being moved fluctuates between 85 and 150 cubic metres per hour.
In practice
The geothermal system fills a 1,500 cubic metre hot water buffer from which the necessary heat is extracted for the greenhouses. The first well is used to heat 7.2 hectares of greenhouses. A second greenhouse of 7.6 hectares is heated with the residual heat. Additional natural gas can be fired if necessary.
Fruitful savings
The energy savings for this company amount to the following:
- Only greenhouse 1 on geothermal heat: savings of 3 million cubic metres of natural gas.
- Both greenhouses on geothermal heat: saving 4.5 million cubic metres of natural gas.
- This company's carbon footprint was reduced by a whopping 74% compared to traditional heating methods.
