Deep Geothermal project at Balmatt site: In 2010, VITO initiated a new 2D seismic campaign covering the area between Turnhout, Herentals and Mol. The seismic data pointed towards the presence of the Dinantian at depths between 2.8 and 3.8 km at Mol. A prospect was defined, targeting the Dinantian near a fault that affected the Chalk Group and older strata, potentially improving hydraulic properties of the reservoir. A drilling location for a vertical exploration well towards the fault zone and the possibly fractured carbonate rocks was found at the Balmatt brownfield site that VITO acquired in Mol-Donk. Proving the potential of geothermal energy at this location and converting the brownfield into a greenfield with a geothermal power and heating plant, is in line with the sustainability goals of VITO.
In December 2015, VITO completed geothermal exploration well MOL-GT-01. The well targets a Lower Carboniferous limestone reservoir at a depth of 3200 – 3400 m. Reservoir temperature is 138 – 142°C. Testing of the first well proved the geothermal potential of the reservoir, and led to the drilling of a second well to close to the geothermal loop. Well MOL-GT-02 was completed and tested in summer – early spring 2016. Both wells will serve as a beat source for a geothermal plant that will deliver heat to the existing district heating network of VITO, SCK and Belgoprocess (planned to be operational in Q3 2018). The geothermal plant also include facilities for materials research (corrosion testing and development of coatings) as well as test facilities for heat exchangers and binary systems.
The initial thermal power output of the geothermal plant will be about 8-9 MW since the return temperature is as high as 80°C. This high return temperature is imposed by the existing high temperature heating grid already in place on the location. Connecting low temperature heating networks that could go as low as 30°C, would double the thermal output. With regard to this addition of extra low temperature heating networks, VITO has already started drilling a 3rd well, MOL-GT-03, which is intended to become a 2nd production well. MOL-GT-03, spudded in December 2017, is targeting the same fault zone as MOL-GT-01-S1, although now in a SE direction at 1.6km distance to MOL-GT-01.