Quantifying Irish Soil Thermal Properties – a reference for improved ground source collector design

Abstract

The Irish Soil Thermal Properties (ISTP) project set out to quantify the thermal properties of Irish soils and subsoils, building on the information of the Irish Soil Information System and further develop a national reference dataset that will facilitate the sizing of ground source collectors. The new data includes thermal conductivity and thermal resistivity, density, porosity and grain size of soils across Ireland. Horizontal closed loop collector suitability maps developed by Geological Survey of Ireland have shown the need for better characterisation of thermal conductivity and moisture content of soils and subsoils. These new data, combined with the EPA/Teagasc and GSI datasets, can provide guidelines for ground source system installation in soil and improve mapping of shallow geothermal energy resources in Ireland. One of the most common problems in the installation of a ground source collector is the reference values of heat delivered per meter of collector installed. Incorrectly sized ground source collectors can have adverse impacts on the environment and can result in increased running costs and CO2 emissions.