Heat from Mother Earth – Shell on geothermal energy ambitions in the Netherlands

Shell gas station (source: flickr/ pony rojo, creative commons)

Alexander Richter 23 Aug 2019

A recent article published by oil company Shell in the Netherlands covers details of Shell’s view on geothermal energy and how and why it is looking into geothermal energy development in the country.

Will people in the Netherlands be heating houses with a heat pump or with geothermal heat? Probably with both, expect Energie Beheer Nederland, Shell and other public and private parties. They estimate that by 2050, geothermal energy will meet one fifth of the demand for heat for houses, buildings, horticulture and light industry in the Netherlands.

Geothermal energy is on the eve of a significant rise. The extraction of geothermal energy is currently taking place at 22 locations in the Netherlands. That number can rise to 175 in 2030 and seven hundred in 2050. By then, nearly four million households will be connected to a heat network and partly “able to burn” geothermal heat. These are figures from the Geothermal Energy Master Plan in the Netherlands of the sector, represented by Energie Beheer Nederland, Dutch Association of Geothermal Operators, Stichting Geothermal Platform and Stichting Warmtenetwerk. They put the plan on the table a year ago in the preparation of the Climate Agreement.

“In the past ten years, greenhouse operators in South Holland have been the first in the Netherlands to gain experience with geothermal energy and thus pave the way for the application of geothermal energy on a much larger scale,” says Eveline Rosendaal, geo-energy program manager at Energie Beheer Nederland (EBN). “The challenge is to create an ideal link in various places between the underground availability of heat and the above-ground demand, so that geothermal energy is affordable and investments in it are profitable.”

Continuously available

Dutch soil lends itself well to heat extraction. Important advantages are that geothermal energy is available almost continuously and that it is a sustainable source of energy. To win it, an operator drills two wells two to three thousand meters deep, one to two kilometers apart. That happens in a place where, according to seismic research, there is probably a layer of porous rock, filled with water from seventy to ninety degrees Celsius. A pump brings that water up through one well. There, it transfers its heat through a heat exchanger to the water circuit of a heat network. The cooled water then goes back into the soil via the other well.

Such a combination of two wells, a so-called ‘doublet’, can provide heat for twenty to thirty consecutive years, day in day out, with the temperature of the water expected to fall little. For the investment to be possible, at least four thousand houses must be connected to a doublet. “Due to the construction costs of heat networks, geothermal heat lends itself primarily to densely populated neighborhoods and in particular to existing neighborhoods. The houses of the most recent new-build neighborhoods are so well insulated that geothermal heating is not economical there. There are also initiatives with shallower wells, networks with lower temperatures and smaller neighborhoods, “says Rosendaal.

Energy strategy

The exact location of the heat networks with geothermal heat and how quickly will depend on the plans of the 30 energy regions in the Netherlands. In line with the Climate Agreement, municipalities, provinces, water boards and other stakeholders in each region draw up a Regional Energy Strategy: a package of measures to achieve the goals for reducing CO2 emissions in that region. The installation of heat networks can be part of this.

“We have extensive knowledge of the soil and the exploration and exploitation of oil and gas resources”

According to Jeroen van Duin, General Manager of Shell Geothermal Energy, Shell wants to play an active role in the Dutch energy transition and be part of it. This is in line with the Paris agreement and with the aim of halving the Net Carbon Footprint (NCF) – or the net CO2 footprint – of the group, to be achieved in 2050. In the Netherlands, Shell is investing in concrete projects such as large-scale wind at sea, solar parks on land, fast charging stations at its gas stations and supplying residual heat to the Pernis area.

Shell Geothermal Energy was established in 2018 with the aim of investing in the development of geothermal heat projects in the Netherlands. “We know a lot about the development and production of oil and gas resources and about working with other parties to implement projects. We can now use this when investing in geothermal heat projects. In this way we also contribute to making the energy supply in the Netherlands more sustainable, “says Van Duin. Last year, the company applied for a first permit for the detection of geothermal heat in an area near Rotterdam. Shell and energy company Eneco jointly applied for a permit in May for the eastern part of the Rotterdam region.

Van Duin: “In the Rotterdam region we know the subsurface from our experience with oil and gas activities. This allows us to determine where we can find a suitable reservoir with warm water. Before we proceed to development, we must ensure that heat production meets the demand for heat. We already have heat networks in Rotterdam that we can connect to. In addition, the city has clear ambitions to make heat demand even more sustainable. ”

There are also heat networks in other large cities, but they are still to be installed in the rest of the Netherlands. “We see cooperation with other market parties and governments as crucial for the development of geothermal heat and heating networks in the built environment. Another condition is that there must be sufficient support from local stakeholders, such as the residents. In short, it requires good interaction between municipalities, housing associations, citizens, energy suppliers and production companies. With a joint approach we can develop geothermal energy cost-effectively, “says Van Duin.

Due to the high investment costs of a geothermal installation, it must actually be able to run continuously throughout the year. Rosendaal: “That is why it is best to use geothermal energy as a ‘base load’ and in the winter when it freezes use an additional heat source for the peaks in heat demand. Such a source can also serve as a back-up for maintenance of the doublet or heat network. ”

In addition to houses, geothermal heat is also a heat source for greenhouse horticulture and light industry. For heavy industry, the temperatures of deep geothermal energy from seventy to one hundred degrees Celsius are too low. Possibly those temperatures can still be raised with heat pumps, but that is not yet a solution for the heavy industry. An alternative could be ultra-deep geothermal energy – for which it is necessary to tap sources at a depth of four to six kilometers – where temperatures prevail around 120 to 150 degrees Celsius. The so-called Greendeal UDG is conducting research into this under the leadership of EBN. Shell Geothermal Energy is involved through NAM.

Manageable risks

According to Rosendaal, safe and responsible extraction of geothermal energy is paramount. “But just like with any other underground project, the extraction of geothermal heat is not without risk. We are aware of this. A great deal of attention goes to reducing risks to an acceptable level and covering them. For example, we are investigating the risk of seismic activity by injecting cooled water into the soil. Furthermore, together with the sector, we are revising the design of hitherto single-walled wells. Just as with oil and gas extraction, good risk analysis and a safety, health and environmental care system are essential for the healthy development of the sector. ”

“As Energie Beheer Nederland we expect to be able to contribute a lot with the development of geothermal energy with our knowledge. On behalf of the state, we have watched and invested for many years in numerous oil and gas projects. This also gives us a good overview of what is happening in the Netherlands. As a result, we are in a position to ask the right questions in collaboration and to bring parties into contact with each other. ”

Citizens choose

Part of the subsurface in the Netherlands has already been mapped out through oil and gas exploration and offers direct prospects for extracting geothermal heat. Other parts of the Dutch soil have not yet been mapped because there has been little or no oil and gas extraction there. Rosendaal: “EBN has been commissioned by the Ministry of Economic Affairs and Climate to map the potential for geothermal heat in these areas with so-called 2D seismics and test drilling. For this we started SCAN, or the Seismic Campaign for Geothermal Energy in the Netherlands. We start in the area from Haarlem to Nijmegen. The larger urban agglomerations are located there, which can benefit greatly from geothermal energy in their sustainable heat transition. The first data on this will be publicly available next year, after which market parties will be able to work more effectively based on this data. Before 2023, we will map all unknown areas of the Netherlands with SCAN. ”

Van Duin anticipates that in the coming period consortia of companies and other parties will develop geothermal energy on a large scale. In addition to investments from parties involved, such as Shell Geothermal Energy, this will include financing from banks and subsidies in the context of the Sustainable Energy Transition Incentive Scheme (SDE ++). “That subsidy is needed because geothermal energy is currently even more expensive than natural gas, even though geothermal energy is the cheapest sustainable alternative in many places. The grant makes it affordable. If we succeed in working increasingly efficiently and effectively over the years, the costs of geothermal heat projects will decrease and the subsidy will become superfluous at some point. After all, the intention is that geothermal heat projects can support themselves. ”

Unlike with natural gas, energy extraction in geothermal heat will literally take place much closer to the citizen. “As part of the energy transition, that citizen will have to choose together with the government what the best options are locally: sunroofs and meadows, windmills, digesters or geothermal heat, or combinations thereof,” says Rosendaal.

Source: Shell