GeoHex - Advanced materials for cost-efficient and enhanced heat exchange performance for geothermal application - will develop advanced materials with anti-scaling and anti-corrosion properties for cost-efficient and enhanced heat exchange performance, allowing the energy of the earth to be harnessed more effectively in geothermal applications. The utilisation of carbon steels instead of CRAs will allow cheaper heat exchangers to be produced and will also increase the efficiency of heat exchangers because of their higher thermal conductivities. However the geothermal heat exchangers are in contact with corrosive fluids, which might cause carbon steels to corrode. Therefore the primary aim of GeoHex is to develop coatings so that carbon steel heat exchangers are protected from corrosion, whilst the coatings also act to enhance heat transfer performance. This will have the dual effect of lowering costs and improving performance.