The former main building of the Houthalen coal mine houses the "Cleantech" service centre, which offers visitors an arc from mining history to sustainable energy production and materials management. On the ground floor there is an exhibition about the mining past. The presentation on the floor above deals with the future of energy and materials. During a guided tour, visitors learn what an energy-friendly recycling economy could look like in the Europe of 2050.
The Houthalen colliery was the last of the seven mines in the Kempen coal basin to start production. Although exploratory drilling had already discovered coal deposits in 1902, construction work on the first mine facilities did not begin until 1927, was interrupted in the 1930s due to economic difficulties, and was completed and the first coal produced in 1939. With the outbreak of the coal crisis in 1958, the mine began its decline: in 1964 it was merged with Zolder Colliery and the coal there was transported to the surface. Material supply and ventilation were carried out via the shafts in Houthalen. In 1992 both mines were closed.