The aubergines are kept warm in the Greenbrothers greenhouses in Zevenbergen. For the time being, the grower is the only one in Brabant to use geothermal energy. By extracting the heat for the glass greenhouses from the earth, the company saves millions of cubic meters of gas every year. Sustainable and good for the wallet, especially at a time when gas prices are going through the roof.
The installation in West Brabant works with two wells of 700 meters deep. Warm water is taken up through one well, the cooled water goes back into the ground through the other well. The water that the grower extracts from the soil is more than 30 degrees Celsius. A heat pump can more than double that temperature before the water enters the pipes. This makes it comfortable even in winter in the greenhouses, where 6.5 million kilos of aubergines grow annually.
The glass growers in Zevenbergen use what experts call ‘shallow geothermal energy’. Normally, the wells go much further into the earth, two to four kilometers deep. The water that then rises is so hot that a heat pump is unnecessary.
Greenbrothers’ sustainable heat source saves 9,000 tons of CO2 emissions annually, calculated installation company Visser & Smit Hanab. That started in 2017 with drilling next to the greenhouses in Zevenbergen. Despite the blessing of the pastor, it took more than two years before the well was ready for use. A leak in one of the pipes and a pump jam caused significant delays.
Frank Groenewegen, one of the directors of Greenbrothers, thinks that this difficult start must be improved to ensure that other greenhouse horticultural companies also want to use geothermal energy. In general, he is satisfied with the installation. “It gives a very good feeling that we no longer need fossil fuels for a large part of our energy needs. That we really participate in a more sustainable earth.”
Not off the ground
The province of Noord-Brabant also wants a sustainable earth. From the 2015 administrative agreement: ‘We see economic and social opportunities for, among other things, solar energy and geothermal energy’ . But where you almost trip over the solar panels, geothermal heat is miles behind. For years it has been quiet around grandly announced projects such as those at the Vossenberg business park in Tilburg or at the Bavaria beer brewery in Lieshout. Other initiatives have not yet got off the ground. Or better: in the ground.
“We started with great optimism. The optimism about the potential of geothermal energy has not diminished, the optimism about the planning has become more realistic,” says Anne-Marie Spierings (D66) with a wink. She became provincial administrator in 2015 with energy in her package and is now again, after a gap of a year due to the rise and fall of Forum for Democracy in Brabant.
Even when she was gone, it was about geothermal energy – in Brabant and the rest of the country. Geothermal energy is playing an increasingly important role in the cabinet’s climate plans. This is a step forward with the system that pumps water from the depths to heat residential areas, greenhouses or other commercial buildings. In practice, it is still mainly greenhouse horticulture companies that take the plunge. Their trade consumes mountains of energy and they often have the size and financial resources to invest millions of euros in the sustainable heat source that is geothermal.
Too ambitious
Spierings would like more companies to transfer, but he also understands why that is not happening yet. ,,We also started with great ambitions, wanted to drill about one well per year. What we subsequently discovered is that we have a complex subsurface in Brabant, with many fractures in it that we actually know little about. There have been hardly any oil and gas extractions here, so the deep subsurface has never been properly mapped out.”
“In all the projects that we initially received, we encountered that we did not know enough about the subsurface, so that we could not sufficiently estimate the safety or the extent to which heat was available in the soil,” continues the commissioner. “We have come quite far in a number of places, but in the end the conclusion was always: we are not going to drill here.”
“In 2018 we were at that point in Tilburg-Noord when we were told by the government that it was too dangerous to drill, it was too close to a fracture. With the risk of tremors and a different flow of water, through the fractures. It’s exciting, you go very deep into the ground,” says Spierings. She also knows: ,,If the first project does not go well, there will be no more. It just has to be safe and that takes time.”
Leaks
Even nationally, not everything goes smoothly. At the beginning of the summer, the Court of Audit sounded the alarm about the possible contamination of our drinking water by geothermal energy. The water a few kilometers deep is full of salt. The pipes through which that warm moisture has to pass are susceptible to rust. If this causes leaks, rust and salt can end up in the freshwater that is shallower and that is extracted for drinking.
The State Supervision of Mines shut down three installations last year due to possible leakages. The national regulator called the risk of mixing salt and fresh water ‘significant’. According to the Court of Audit, the government ‘does not sufficiently understand the urgency of the problem’. In any case, there is still a lack of specific regulations for geothermal energy, too often the sector has to figure it out for itself.
Pioneering it is. This is done, among other things, with a double-walled construction in the wells, which considerably reduces the risk of leakage. “That stems from a guideline we drew up in Brabant and which has been adopted nationally,” says Spierings, quite proud.
“You see it more often that if you start doing something new, the legislation will follow. This provides clarity for everyone, especially for companies that make the wells. That they know exactly what they have to meet. That legislation will also be introduced: the central government has recognized that geothermal energy is an important technique in the energy strategy.”
Geothermal energy Brabant
Geothermal Brabant partnership is leading the charge for the province. That club includes the company Hydreco Geomec and the Brabant Development Company (BOM), which helps companies and innovations on behalf of the province.
Harmen de Kool is busy with geothermal heat for the BOM. He knows that exploration permits have been applied for in Eindhoven and Oss to explore the possibilities for geothermal energy. Projects in Made, Tilburg and Someren-Asten have already received permission from the Ministry of Economic Affairs and Climate (EZK). That does not mean that the drill can go straight into the ground. Preliminary research is required first: is there heat, how great is the demand, is it safe? It is also still bursting with snags.
Take the project in Someren and Asten, for example, where a group of greenhouse horticulturists wants to invest in geothermal energy. The Ministry of EZK asked three authorities for advice before granting the exploration permit. TNO and the State Supervision of Mines saw no objection, but the Mining Council has its reservations. That advisory body does not dare to rule out the possibility that earthquakes may occur after drilling in the area of ??the Roer Valley, which covers a large part of Central and East Brabant.
The province is now first asking for clarity from the government. Without that clarification, parties that work together in Geothermal Brabant do not want to start drilling. The glass growers in Someren and Asten are now training their patience.
Research into the possibilities of geothermal energy is also underway in other provinces. Scientists are concerned with the risk of earthquakes. An installation in Grubbenvorst, Limburg, was previously shut down after the earth shook twice. In Brabant, the province is arguing for more seismic monitoring stations to record any natural vibrations before drilling.
“I think we are now at a point of: how are we going to cash in on the promise of geothermal energy?”, says De Kool on behalf of BOM. He argues for a geothermal law, tailored to geothermal energy. “Now we still work under the mining law, while that is really different. You also work in the soil for oil and gas, but we get nothing out of it. The water that we pump up also goes back into the ground. And there are even more differences that you should make your own law for. Even if it corresponds perhaps seventy percent to what we have now.”
Specific guidelines and conditions not only give initiators a better idea of ??where they stand, the outside world also gains more insight into this. That can help with financing, as it becomes increasingly difficult to get money as long as banks read stories about earthquakes, groundwater pollution, unclear rules and other obstacles.
Substantial investments
Money is needed. A test drilling to find out exactly what is in the subsoil costs four to five million euros – says De Kool. The investment is substantial and the risks of failure are substantial, but once it works, you have a sustainable heat source, Spierings is keeping the spirits up on behalf of the provincial government. She knows that heat is one of the most ‘complicated issues’ in the transition to sustainable energy and the elimination of fossil fuels.
“In industry, heat is needed all year round, in residential areas especially in winter. But then you have the least generation of electricity by panels, because the sun shines less. If you have a good source of heat, you cover that issue.” The high gas price only further boosts Brabant’s ambition.
The commissioner therefore remains optimistic about the possibilities with geothermal energy, especially for greenhouse horticulture and districts that are connected to a heat network. “It is interesting for large buyers. This is simply too expensive for ten or twenty homes.” Spierings has reason to be hopeful. With a project called SCAN, the government is providing a better picture of the Brabant soil. Energie Beheer Nederland is currently working on this in Oss and the surrounding area. And in The Hague too, more and more attention is being paid to the need for legislation and regulations.
How does the Commissioner see the future? “If no new well is active in Brabant by 2030, I would find that very strange. Then we have probably all concluded that geothermal energy is not the solution.” Slightly concerned: “That would immediately present a major new challenge in the energy transition.”
