TNO: Half of the Netherlands could be heated by geothermal Energy

Amsterdam, The Netherlands (source: flickr/ ChrisYunker, creative commons)
Alexander Richter Alexander Richter 2 Nov 2018

According to independent research organisation TNO, the Netherlands could cover nearly 50% of its heating demand with geothermal energy paired with heat storage.

In a recent article, TNO (Nederlandse Organisatie voor Toegepast Natuurwetenschappelijk Onderzoek) – a Netherlands-based independent research organisation – makes an argument that “geothermal energy coupled with heat storage in the soil can in time provide for a large part of Dutch heat demand.” In the same article, TNO makes the point that  ‘a kind of IKEA package’ is needed to reduce the heat demand in homes.

TNO wants to pump more hot water from the deep underground and temporarily store it in shallow reservoirs. These could also act as a battery for solar heat and industrial residual heat. “In theory, we can connect two-thirds of the Dutch households to a heating network and feed half of them from geothermal energy”, says specialist Maurice Hanegraaf of TNO. Whether such a scale is realistic is uncertain, but the knowledge institution is serious about the large-scale use of the CO2-neutral, infinite heat source.

At the moment, the Netherlands has 17 doublets (double deep wells) for geothermal energy, together accounting for a heat production of 3 PJ per year. They are only used by greenhouse horticulture. By multiplying that number by 2030, a production of 50 PJ is possible, enough for heating 700,000 homes. According to TNO, some 700 doublets could provide the lion’s share of the Dutch heat demand by 2050.

Temporary buffering of hot water from the deep underground in shallow reservoirs enables continuous production

The obstacle is the big one. The construction of 175 doubles in 2030 would cost EUR3.5 billion (about $4 billion). The payback time is too long because they can only produce in the summer. Temporary buffering of hot water from the deep underground in shallow reservoirs enables continuous production. The price of deep geothermal energy can therefore be reduced by 40 percent according to calculations by TNO, and by heat networks by as much as 50 percent.

Research project ‘Heatstore’, which started last week, will explore the possibilities further. Part of this project is a heat storage that is 400 times larger than the largest battery in Europe. ECN (part of TNO) leads this European project with 23 parties from nine countries. Heatstore explores storage technologies in combination with various heat sources: geothermal heat, solar heat and residual heat. This is happening in six European pilot projects, including one in North Holland. This uses water of 80 degrees Celsius from a source at about three kilometers depth.

The number of thousand houses that are now being rebuilt every year must go to a thousand per day

The focus on geothermal energy is related to the plans to make the Netherlands natural gas-free. TNO would prefer to see a ban on central heating boilers, but this billion-dollar operation barely yields when the replacements – heat pumps – will soon run on electricity from a coal-fired power plant.

In urban areas, heat networks that (partly) run on geothermal energy can be decisive in achieving energy neutrality, TNO thinks. Provided the houses are thoroughly insulated at the same time and equipped with durable equipment. The number of thousand houses that are now being rebuilt every year must go to a thousand per day.

“And we need an industrialization of renovation solutions for homes from before 2000,” says Huub Keizers (TNO). “A house should be ready within five days of inconvenience.” According to him, this can only happen if the fragmentation in the chain comes to an end. According to him, suppliers of heat pumps, insulating products and PV panels work together and put together ‘a kind of IKEA package’. “That benefits the working speed and the price. It can go down by 50 percent. ”

This is indeed an interesting research and similar research has been done in Germany highlighting the p0tentially huge role for geothermal energy there as well. The point on the summer vs. winter use and thereby challenges of year round utilisation and its possibility in storage, neglects the potential of producing electricity. But that naturally depends on the available temperatures. With current technological solutions electricity could be generated from resources as low as 70 degrees Celsius. While likely pricey, it still is an option if possible and economically feasible.