Geothermal heat – the sustainable energy of the future for the Netherlands
A recent meeting of the international geothermal community in The Hague highlighted the great efforts and payoff of the geothermal ambitions in the Netherlands, where geothermal energy is seen as a beacon for the energy future of the country.
Every hour three hundred cubic meters of salt water, almost 80 degrees Celsius. That is twelve trucks full. So much salt water is pumped up day in and day out at a single well in Middenmeer in North Holland. And all that water goes through another tube, cooled down considerably, back into the ground under pressure. About two kilometers deep.
“A huge amount,” says Robert Kielstra when he arrives at the pipe system. The greenhouse area near Middenmeer, about 400 hectares in size, is partly kept at the right temperature by geothermal energy . As a result, a quarter less gas is needed. And for that, three production and injection wells are needed, which are called doubles per two.
We will probably see these “doubles” more often in the Netherlands, because geothermal energy is attributed an important role in making energy production more sustainable. Kielstra, director of the local energy company and network manager ECW, mentions the large quantities of water to give an indication of the complexity. “We have been using the warm water from the soil here for five years. At a number of moments we thought we had completed the pioneering phase, but we are still in a learning curve. ”
The horticulturists, who take the heat from ECW, play the largest role in the development of geothermal energy. The Netherlands now has more than twenty doubles, almost all of which were installed on the initiative of growers.
If it is up to the government, it will not stop there. In the year 2050, the country may also no longer emit greenhouse gases in energy generation, and “we can’t make it with just sun and wind,” said Sandor Gaastra, Director General of Economic Affairs and Climate Change at (the European Geothermal Congress) in The Hague last week. Geothermal energy can play an important role, Gaastra told his international audience, but only if the number of heating networks (district heating) will multiply in the coming years. “We are spoiled here by an abundance of gas.”
The starting position is attractive. Every hundred meters you go deeper into the bottom, the water gets three degrees warmer. If you drill two kilometers, you will find water of almost 80 degrees, warm enough to heat greenhouses and houses. A third of the energy in the Netherlands is used for heat. Partly for the heating of houses or shower water, partly for industrial use.
“Our ambition is to reach 75 doubles in 2025, which means a triple increase,” says Frank Schoof, chairman of the Geothermal Platform, which bundles producers, suppliers, customers and public parties. In 2050, the year that senior civil servant Gaastra called, the ambition is even at 700 wells.
Schoof calculates: “In the proposals for the climate agreement we assume that half of the houses will be connected to a heat network. We think that half of the heat required for those networks comes from geothermal energy. ”More than half is not obvious, because you cannot turn off a well in the summer. The geothermal energy always provides the basis for the heat supply, the peaks – for example in the winter – have to be filled in differently.
Schoof: “We really need the support of politics. Of course, the sector needs to become more professional, more standardized and less dependent on subsidies. But without the arrival of more heat networks, there will be no customers – and we as a sector cannot control that. ”
To lift geothermal energy in the Netherlands to a higher level, minister Eric Wiebes (Economic Affairs and Climate, VVD) puts forward state-owned company Energie Beheer Nederland (EBN). This is now included in all gas and oil drillings in the Netherlands, and in two hundred cases it also takes part financially. Anyone wishing to drill for hot water from next year, if the Mining Act has been amended, will probably be required to first ask EBN for coffee.
“We are currently working to fulfill our role in this,” says Eveline Rosendaal, geo-energy program manager at EBN. “That obligation to invite EBN already applies to oil and gas drilling, and we then decide whether to participate in a project.”
Wiebes has allocated EUR 50 million for the next five years. EBN can use that money for projects. It doesn’t seem that much – a doublet costs 15 to 20 million euros – but with the participation of EBN, an operator can raise a multitude of debt.
At present, around twenty people are working with geothermal energy at EBN. Rosendaal: “We still have white spots in the Netherlands with regard to our knowledge of the deep subsurface. And not every layer is suitable for extracting water from it. An example of such a white spot is the line from Haarlem, Amsterdam, Utrecht to Nijmegen where many people live and there is a high demand for heat. ”
Without a view of the deep subsurface you do not know whether (efficient) hot water can be extracted. In areas where oil or gas were once drilled, such as the Northern Netherlands and South Holland, this knowledge is there. Rosendaal: “We ensure that municipalities, provinces and companies receive the data with which they can make choices for the future.” In 2021, every municipality must have a transition plan ready for each neighborhood.
It is not only the presence of recoverable water that will be important for local politics. Because what about the risk of earthquakes if drilling is done so deeply? No alderman wants to bring Groningen problems into account when constructing a heating network.
“Everything you currently do in the subsurface receives extra attention. And rightly so, “says Rosendaal of EBN. “But you have to see it in proportions: Groningen is a very large gas field that is now very empty. The pressure differences are large there. With geothermal heat, extraction is much more local. Moreover, the mechanisms in the subsurface are different, because you also put the cooled water back. ”
The State Supervision of Mines Supervisor (SSM) has previously observed that quite a few ‘hot water wells’ do not have the quality that they are used to with oil and gas drilling. There are more problems with extraction and more maintenance is needed.
>”With geothermal energy you have to deal with salt water, which causes corrosion, and in the event of a leak, mixing can occur between fresh and salt ground water. That is not allowed and is very undesirable for the drinking water supply, ”says sector leader Robert Mout of SSM. “Another big difference is that oil and gas naturally come out of the ground at a well, but you have to pump water. And such a pump, which is hundreds of meters in the ground, can also cause damage in the well ”. Measures to prevent corrosion naturally lead to additional costs.
Mout also notices that many people have become more critical due to the events in Groningen. “Mining is not without risk in the Netherlands. This also applies to geothermal heat. We want to see the realization that there are risks involved, that it is an industrial activity, at every company. ”
This critical view does not only apply to companies. Mout: “We monitor safety, even if a municipality or province is in charge and therefore the operator. And it is no fun for anyone if, for example, we are confronted with a municipality. The law requires that there is sufficient expertise. That is a concern for us.”
Salt on slag
SSM is also a frequent guest at energy company ECW in the Middenmeer greenhouse area. Kielstra: “Sometimes there was a difference of opinion, sometimes I thought they put salt on snails, but I also certainly experienced that we thought: how could we have overlooked that?”
In the meantime, ECW, which employs thirty people, has five doubles. In April the king and minister Wiebes visited two doubles for gardeners in nearby Andijk. The energy company is discussing heat networks with other municipalities. Kielstra understands the concerns of SSM. “For a windmill you can go to one contractor who takes care of everything. With geothermal energy, contractors do not have this integrated knowledge. We hire people for everything that needs to be done here. But the overview is with us; that is why we have taken the flight forward. ”
Schoof of the Geothermal Platform notes with satisfaction that major players such as Shell, Eneco, waste management company HVC and the Canadian company Vermilion are showing interest. He also believes that EBN’s participation adds value. He does think that the sector must find a new balance. “Many operators will find that they themselves already have a lot of knowledge. They will point out that EBN itself has no experience with geothermal heat sinks. And EBN’s money is of course not free either. I think politicians should realize that promoting financial innovation and professionalization requires extra financial resources. ”