geothermal heat
Trias Westland hits on virtually impermeable layer of rock
Although the 4km-deep hole drilled by Trias Westland provided a ‘wealth of data’, the extraction of sustainable heat from the Trias layer is not sufficiently profitable. The organisation has therefore decided to fall back on Plan B and extract warm water from the Lower Chalk layer. This option is anticipated to deliver 19 to 22 MW, which is not enough to supply all the growers that have committed themselves to this project with geothermal heat.
A core of 30 metres of stone was brought up in the last specimen extracted from the drill hole. A study of this core revealed that the porosity (permeability) of the rock from the Trias layer was zero. This means that the flow of water at this depth is very difficult, if not impossible. Additionally, traces of gas were discovered in the pores of the sandstone, rendering the performance of a normal well test using a pump impossible. “An enormous disappointment,” says Floris Veeger, project manager for geothermal heat of Trias Westland. This prompted a decision to close off this deep section with two concrete plugs and to extract heat from the shallower Delft sandstone layer, in line with the other projects in the Westland area. This was disappointing for the participants and initiators, because no new layer of soil was made accessible that would help phase out the dependency on natural gas in the province of Zuid-Holland.
Well test
The Delft Sandstone Layer is nevertheless thicker and more permeable than anticipated. Apart from this, an additional layer of sand (at a greater depth) was discovered, which will not be used for this project, however. The organisation expects to extract water of a temperature of 85 to 90 degrees from the Delft Sandstone layer, at a depth of 2.3 km. The first well test is expected to take place next weekend. If, after this, the definitive decision is made to drill the second well, a second well test will take place at the end of April which will provide more information about the exact heat yield of the geothermal project. To be able to provide all participants with sufficient geothermal heat, a second doublet will be necessary. Director Marco van Soerland does not exclude that Trias Westland will do this, even though no concrete plans have been drawn up for this purpose. The potential yield in geothermal heat from the Lower Chalk layer in the Westland area is estimated at 300 to 400 MW.
Text/photos: Mario Bentvelsen.
Related
Over thirty growers are interested in geothermal energy from a depth of 4 km
KP Holland is one of the thirty growers who have signed an agreement to participate in the geothermal project Trias Westland. If the drilling is successful, all the participating growers will get a connection to the geothermal energy coming from the Triassic layer, at a depth of 4 kilometres. This geothermal project for horticulture will be unique in the world.
In the past months, 65 companies have expressed interest and thirty growers have already committed themselves to this sustainable initiative. The total power for which the letters of intent were signed currently amounts to about 60 MW. One of the companies is KP Holland, a horticultural business in Westland that sees sustainability as one of its core values. A sustainable energy supply for the family business is therefore a logical step. KP Holland is a global supplier of young and flowering plants of Kalanchoe, Spathiphyllum and Curcuma.
According to Roy van der Knaap, manager of energy and technology, geothermal energy is one of the few alternatives to fossil fuels. The stock of fossil fuels is limited, it is bad for the climate and with the current global developments the delivery can sometimes be uncertain. "The project Trias Westland fits well with our company and philosophy. We embraced it wholeheartedly and full of enthusiasm."
Ceiling price
The participants will be closely involved in the development of the project and will become co-owner without having to invest themselves. The price that is paid by the participants is based on actual costs, including a reasonable compensation for the risk capital of the founders of the project. The fact that there is a 'ceiling price' offers more security for the participants.
According to the director of Trias Westland, Marco van Soerland, not all growers who have shown interest have signed the actual agreement. "Those who have not signed, may not be able to because they are in between two other geothermal energy initiatives and are forced to wait. But there was a lot of interest in the project and there still is now. "Van Soerland expects that the negotiations with all the parties will be finished in April.
New participants are still welcome, but speed is of the essence. "Applications can continue, but we will start shortly with the development of the different scenarios and therefore it is necessary that we know exactly who wants to join." Only after the exploratory drilling it will be clear how much heat will become available.
Combined drilling
In order to limit the (financial) risks of the exploratory drilling, a combined drilling is done. This means that first they will drill to the Lower Cretaceous-layer at a depth of 2 to 3 km. After examination of this layer they will continue to drill to the Triassic layer at a depth of 4 km. If the Triassic layer is unexpectedly found to be unsuitable for the extraction of geothermal energy, a Lower Cretaceous doublet will be realised. In which case, the purpose of the exploratory drilling - determining the suitability of the Triassic layer – is achieved, costs are reduced and a profitable Lower Cretaceous project will be realised.
If the Triassic layer is suitable, 30 to 50 growers can be connected to the geothermal heat source. If that is not the case, a Lower Cretaceous project will be realized and approximately 20 to 30 growers could make use of geothermal energy. In both scenarios, the most economical connections are realised first. Growers who are closest to the drilling site and whose neighbours have also joined the project have the best chances.
Source: Trias Westland. Photo: Mario Bentvelsen.
Second geothermal drilling project in Californië a success
Drilling commenced at the end of 2015 for a second geothermal well in the Californië horticultural area located just to the northwest of Venlo in the Netherlands, 1½ kilometres from the geothermal well operated by greenhouse horticulture firm Wijnen Square Crops. Sustainable heat was sought - and found - at 2,500 metres below the surface, and will be used to heat existing and newly built greenhouses in the surrounding area.
Construction of the second doublet was in the hands of property developer Californië BV and three horticultural firms: namely those belonging to Frank van Lipzig, Roland Gielen and the van Leeuwen brothers, Thomas and Jordan. Drilling operations started on 3 December 2015. Exactly two months later the production well was tested. The result was a maximum yield of 375m3 per hour, at a temperature of 80° C.
The growers involved in the project are ecstatic. The decision was made immediately to start drilling an injection well. If the results obtained here are just as good, the three horticulture firms will be able to turn off their gas supply almost entirely. Not only that, sufficient geothermal heat will be available for the adjacent 20-hectare plot of land as well.
Beyond expectation
The injection well will be tested in March. The above geothermal system will be constructed in spring, and the supply of geothermal heat is expected to commence in the course of next autumn. The heat will be distributed to three horticulture firms, at which tomato and cucumbers are grown and that cover an area of 26 hectares collectively. The costs associated with drilling the wells and the installation of the pipes amount to 13 million euros.
Drilling operations are executed by T49 at KCA Deutag, the company responsible for drilling the geothermal wells operated by the Aardwarmte Vierpolders Collective. The necessary mining engineering expertise is being provided by WEP (Well Engineering Partners) and the project is being supervised by Radboud Vorage, the agency that was also in charge of the Koekoekspolder Project.
Source: http://www.californie.nu/www.geothermie.nl Photo: Mario Bentvelsen.
Vierpolders geothermal well taken into operation
The Collectief Aardwarmte Vierpolders geothermal heat well has been taken into operation. Although this is a few months later than planned, Paul Grootscholten has nothing to say about the cause of the delay except that: ‘you can make plenty of plans, but there are always surprises.’
The well is currently producing a temperature slightly above 80°C. The secondary water is further heated by another 5°C, using the gas that is emitted as a by-product. The collective’s horticulture systems are now being adjusted to send the cooled-down water to the heat exchangers at the lowest temperature possible. All systems and the new regulatory mechanisms will be tested extensively during the next few weeks to come.
Test run
‘It is our goal to be able to operate at minimum capacity throughout the month of February, with a view to achieving a constant temperature regulation. We expect to be able to increase this in March, and to see how everything will respond,’ continues Grootscholten. During the ‘Kom in de Kas 2016’ event on 2 April a big part of the geothermal well site will be accessible to the public.
Collectief Aardwarmte Vierpolders is an initiative launched by eight horticulturists on an area covering 50 hectares of greenhouses. Drilling operations started in the summer of 2015, and the first hot water was pumped up to the surface on 12 August. The anticipated capacity of 17 MWth in geothermal heat will be enough to satisfy the heating demands of all eight affiliated potted plant and vegetable growers.
Source: Collectief Aardwarmte Vierpolders. Photo: Mario Bentvelsen.
Room for 324 MW geothermal heat in the Westland and Oostland regions
On 21 January 2016 a seminar was held at Priva in De Lier with the title ‘Geothermal energy, how difficult can this be?!’ Geology and engineering, as well as all the financing, success factors, benefits and risks associated with geothermal projects, were discussed extensively during the seminar.
Coen Leo, manager at PanTerra Geoconsultants, has many years of experience in geology. He explained why you can’t simply start drilling at random locations. He summarised the numerous risks in the fields of geology, engineering and operations and discussed how these could be kept in check. According to Leo, there are abundant opportunities in the Westland and Oostland regions for new geothermal projects. ‘The 70 megawatts that six working doublets can currently produce could be increased to 324, based on the available space below ground.’
Peter de Vreede, a geothermal heat specialist at Flynth, zoomed in on the organisational and financial factors and risks associated with geothermal heat. ‘As a grower, you need neighbours who will join you in setting up such a large-scale project. The project organisation and management of a geothermal heat cluster are key success factors.’ With regard to finances, it become clear that SDE Renewable Energy Production Incentive programme was highly relevant, while the MEI Market Introduction Energy Innovations programme will no longer apply to geothermal heat.
Frans-Peter Dechering, general manager at Priva, appealed to growers to stop focusing exclusively on the financial side of the matter. ‘Customers, society and nature are factors that cannot be overlooked. Consider the possibility of supplying the residential market with geothermal heat. Another factor associated with geothermal heat is its smaller carbon footprint. Besides this, it will help us decrease our reliance on oil.’
‘Not geology, but a crystal ball’
Jos Scheffers spoke of his experiences with the Green Well Westland project, a geothermal heat well to which ten growers are connected. ‘You can’t rely on geology; it’s more like gazing into crystal ball: the initial results remain unpredictable for a very long period of time,’ according to the entrepreneur. ‘You never know in advance what your flow rate per m3 per hour will be.’ Nevertheless, Scheffers is highly satisfied with the ultimate result. ‘Until today, this project has covered six years in which we have had to deal with numerous surprises. However, if asked, I would gladly do it all over again.’ He would, however, spend a little more time on choosing his materials. ‘You call in external advice because you don’t have the expertise you need. Based on what I know now, I would have made different choices.’
The seminar’s organisers PanTerra, Flynth, Priva and the Platform for Geothermal Energy look back in satisfaction at a successful event, with a full hall and plenty of interaction and in which a great deal of knowledge was shared.
Source/photo: Priva.