Friday 8 july the 2nd Dutch Geothermal Congress was held, organised by the students at the Earth Sciences Society Utrecht. The two main themes of the Congress were: Deep – Extraction of Geothermal Heat and Shallow – Storage of Thermal Energy.
I was there to talk about the factors that determine the efficiency of Geothermal Heating (Ground Source Heat Pump) systems and how these relate to the practical situation in the Netherlands. The Netherlands leads the world in this and our KWR building also has a GSHP system. We are looking at how to optimise the source design of those systems. From the research I am undertaking together with Niels Hartog it appears that losses due to background flow and conduction play an important role and these are not always taken into consideration in the design. The background flow in particular has not been taken into account because until recently there was no method for measuring it but we have now developed a method for that.
Niels also talked about the future and the added value for Underground High Thermal Energy (30-90C) Storage (HTO) and the technical developments that are further contributing towards that. At KWR we are working to develop the use of HTO for the greenhouse horticultural sector in particular and for the interconnection of heat grids.
From my doctorate research there was also a presentation by my colleague from the Delft University of Technology, Jan Kwakkel. He talked about the trade-off mechanisms between individual yield and maximising CO2 emission reduction in an area with a high density of geothermal systems, showing how to quantify this and also making a number of suggestions for optimising it by using adaptive permits.