Mol, 2 July 2015: After the launch of an international call for tender, VITO assigned the soil drilling on the SOV-Balmatt-site up to a depth of 4 km to the THV Balmatt Drilling, founded by the German drilling company Daldrup & Söhne AG and Smet Group from Dessel. Both companies are experts in soil drilling.
The first drilling on the site, for which the works will start mid-July, will be realised before the end of this year. A drilling to such depths is a valuable research project, unique in Flanders. The results of the exploratory drilling are expected by December 2015 and are crucial for the further course of this pilot project. Eventually, the energy from the deep subsurface will be used to heat buildings. Besides its own VITO buildings, other nearby companies and homes may also join by means of a heating network. Furthermore, the energy will also be used for the production of sustainable electricity.
This project is made possible by the financial support of the Flemish government (Enterprise Flanders and the government agency for Innovation by Science and Technology) and framed by the EFRO project 910: GEOTHERMIE2020, a collaboration between IOK (Intercommunal Development for the Kempen), VOKA Kempen (Flemish network of companies) and VITO.

Drilling to unknown depths

Drilling up to nearly 4 km has never been realised in Flanders before. Therefore the research value is very high, but so are the risks. For this reason, VITO has carried out multiple preliminary studies in the last few years. The researchers developed models based on the results of the seismic campaign, which VITO carried out late 2010 in Herentals – Mol – Retie, and data from the Database Subsurface Flanders. From this, a design of the drilling was drawn up, taking into account the expected composition of the soil layers, the occurrence of water, the pressure in the subsurface and the pumping of hot, salt water from a depth of 3 to 3,6 km.

The drilling is an excellent opportunity to gain new knowledge about the deep subsurface of the Kempen. VITO will perform an extensive measurement and sampling programme in order to collect as much data as possible about the composition and physical characteristics of the deep soil layers. Moreover, so-called cores will be taken from a depth of 3 km. This is unique in Flanders. What the experts can learn from this, is of extreme value for refining the models of the deep subsurface.

Neighbouring company NIRAS is already going to use this newly developed knowledge about the deep subsurface in terms of research into the underground storage of radioactive waste. To this end, NIRAS contributes financially to map the first hundred metres of the subsurface, taking into account specific parameters.

Reaching out for new financial resources

The investment costs for the Balmatt project, resulting in an operating deep geothermal energy station, could amount to 22 million euros. The first drilling, VITO will largely finance with own funding, plus an additional amount of 2 million euros from the Flemish government. As a deep geothermal energy station needs at least 2 wells, an adequate, additional bank financing has to be found for the second drilling. The results of the first drilling will give a clear indication of the extent of the further investment.

Energy straight from earth

Based on preliminary studies, VITO expects to find sufficient temperature and output to supply in any case her own heating network with hot water of about 90 °C. In case the condition of the subsurface is very favourable, 2 to 3 additional drillings can be performed at the same location. As a result, large parts of Dessel and Mold can be supplied with hot water.

The advantages of this green heat are its 100 % sustainable nature, its independence from price fluctuations of oil and gas and its local embedding. The electricity that would be generated is also 100 % green energy. In an optimistic scenario, the electricity production could rise up to 9 MW. Moreover, the power production is independent of weather conditions (wind, sun,…) and almost continuously (24 h/day, 7 days/week) available.

More info on deep geothermal energy:


Share this article
+32 14 33 55 85