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After challenging start, The Hague to tap into geothermal energy for heating

The Hague geothermal heating plant (source: Haagse Aardwarmte Leyweg)
Alexander Richter 12 Aug 2020

After technical challenges and a bankruptcy, the geothermal project in The Hague in the Netherlands is now going ahead with first houses to be able to tap geothermal energy for heating in the autumn of 2020.

Starting this autumn, hundreds of houses in the southwest of the city of The Hague in the Netherlands will be heated with hot water extracted at a depth of more than 2 kilometers. Next month, the Ministry of Economic Affairs and Climate (EZK) still has to give the green light for the extraction plan, so an article in NRC.nl.

On the site of the Eneco boiler house in The Hague, which looks like a cathedral – or crematorium as others see it – then Crown Prince Willem-Alexander kicked off the The Hague geothermal energy project in the summer of 2012. A proud alderman Rabin Baldewsingh (PvdA) watched with 175 guests as the crown prince symbolically initiated the extraction of geothermal energy. But in the past eight years, not a single house has actually been heated by geothermal energy.

There were technical problems, but above all there was a financial crisis: the thousands of houses that were to be connected to sustainable district heating were not built or were built with a long delay and a year later the project of the municipality, housing corporations and energy companies was bankrupt.

The fiasco quickly led to a new initiative. “We took over the estate five years ago,” says initiator Jan Willem Rösingh of Perpetuum Energy Partners (PEP). That estate was mainly the successful – and costly – drilling work that had been done. “Thanks to the existing wells and the subsidy for renewable energy, we are convinced that we can be profitable with 2,500 connections. Normally you would need at least twice as many houses to make no loss. ” That number of 2,500 houses, partly new construction around the Haga Hospital, must be reached in the next five years.

Technology in the start-up phase

The costs for geothermal energy projects are high, especially because the technology is still in the start-up phase. “In that respect it cannot be compared at all with other sustainable forms of energy, such as wind and sun. The costs of this have fallen rapidly in recent years, with geothermal energy the costs have only increased, ”says Rösingh. “In the Netherlands we only have 23 projects where heat is currently produced.”

This mainly concerns horticulture, in which greenhouses in Westland and North Holland in particular are heated with geothermal energy. Cities such as Zwolle, Almere and Leeuwarden are now also looking for sustainable geothermal energy for some of their residential areas, but the Geothermal Energy Leyweg (HAL) in The Hague seems to be taking the scoop.

Geothermal energy is one of the ways to get districts off gas sustainably. “Sustainable heat in particular is very scarce,” says Rösingh. “For example, I don’t see the large-scale use of biomass growing rapidly in the Netherlands.”

With a share of 40 percent, the heat supply for Dutch houses and factories is the country’s largest energy consumer. “As a municipality, we are very proud that this year we are getting a geothermal plant in the built environment up and running,” says alderman Liesbeth van Tongeren (GroenLinks), responsible for sustainability in The Hague. “As far as we are concerned, it is certainly not limited to the installation on the Leyweg. In the shorter term, we have plans for four or five other drilling locations. ”

This time, the municipality is only indirectly involved in the geothermal heat project through the Energiefonds The Hague. Hydreco Geomec, subsidiary of energy company Engie and responsible for the technical side, forms the private side of the project with PEP from Rösingh. According to Rösingh, the private participations together have an equal interest in HAL as the municipal fund. “We consciously opted for private-public cooperation to safeguard all interests.”

And it still involves substantial amounts. Up to 2012, some EUR 20 million have been invested. The current partners think that another EUR 10 million need to be added to really get the project off the ground. “When the funding was finalized, we opened and inspected the wells. They had stood still for years and of course you work with salt water. But after a thorough cleaning everything turned out to be in order, ”says Rösingh. Incidentally, that salt water will not flow through the radiators in the living room: the heat from the salt water is transferred to the heat network by means of heat exchangers.

Initially, it was intended that heat production would start in 2018, but the required new permits in particular took a long time. Since the earthquakes at gas extraction in Groningen, the regulator has been afraid of new problems. And here it is also an urban area. “Organizations such as TNO and the Haaglanden Environment Agency are also taking a critical look,” Rösingh knows from experience. “If necessary, they raise the alarm, and that happens regularly. That is good, it only gives confidence for the environment. ”

Incidentally, the comparison with the drilling in Groningen is not valid, says Bas Kuilman of PEP, just like his colleague Rösingh mining expert. “We do not disturb the ground. There are two wells. The water that we pump up from one sandstone well goes back to that same layer of sandstone via the other well. So we only extract the heat. With gas extraction you really get something out of the ground. ” The water comes out of the bottom at about 78 degrees Celsius and returns at 55 degrees Celsius to a depth of over 2 kilometers.

Yet geothermal energy also has a recent incident: in Venlo, the drilling process was halted by SSM in 2018 when a small earthquake occurred. “I don’t know exactly what happened then, but the subsurface there cannot be compared with the sandstone under The Hague. As a result, the method also differs, ”says Kuilman.

Parking lot

The wells are located behind Eneco’s red boiler house, but more than two concrete bottom plates – under which pumping up and backflushing takes place – are not visible. “We do as much as possible underground to limit the nuisance,” says Kuilman during a tour. “The pumps are located close to the wells, and are also all installed underground. The neighborhood will therefore hardly notice it. When we have completed the installation, it will simply become a parking lot for hospital staff. ”

According to him, the neighborhood notices little or nothing of the heat production, even if there is a fault in the pump installation. “As soon as you stop pumping, the water sinks. An extra gas boiler prevents the neighborhood from being left out in the cold in the event of malfunctions. ”

The heat is supplied to Eneco’s existing district heating system. As usual with a heat network, a so-called heat exchanger in the meter cupboard at the resident’s area provides heat for heating and tap water. Whether that heat is gas-fired or comes from the earth does not feel different for the resident.

Alderman van Tongeren is not afraid of opposition to geothermal energy. “The people are already connected to a heat network. Some like the fact that geothermal energy makes it sustainable, others don’t even know it. Of course, drilling is done in the city, but I think there is no energy type without a downside. If you strive for a clean and safe environment, you want no air pollution, no noise and preferably no major changes in your home. That is the case with geothermal energy. ”

The municipality has formulated additional requirements in response to the extraction plan that is now on the desk of Minister Wiebes (EZK). In this way, the city council wants to get a better picture of how local residents are informed about the project. The municipality also wants to know which authorities are notified, for example the Haaglanden Security Region, if ‘seismic activities’ are detected. Van Tongeren: “The Hague wants clean and safe energy and that is why it is good that such an extensive check is done by regulators and the ministry.”

Geothermal energy in The Hague may be unique for ‘gas country’ in the Netherlands, but cities abroad have been heated sustainably in this way for much longer. Such as Paris and Munich.

Rösingh: “In the Netherlands we have only had experience with horticulturists for about twelve years, and they require heat almost all year round. In the built environment, that demand largely disappears in the summer. ”

That period must be bridged as efficiently as possible. Few residents of The Hague will want to pay more for their heat, just because it comes from the ground. “We have an exploration permit for geothermal energy for the whole of The Hague and we want to open more locations. Then we first have to demonstrate to the Leyweg that we are sustainable, reliable and competitive in price. ”

Source: NRC