European Geothermal Energy Council
Magyar Állami Földtani Intézet
Agency for geothermal power engineering
Union of Bulgarian black sea local authorities
Slovensko društvo za daljinsko energetiko
Consorzio per lo Sviluppo delle Aree Geotermiche
Association Française des professionnels de la géothermie
Polish Academy of Sciences – Mineral and Energy Economy Research Institute
GronEnergi
Gemeente Heerlen
