In situ characterization of thermophysical soil properties-Measurements and monitoring of soil water content with a thermal probe

In a period of surging energy prices, resource depletion, and concerns over the use of nuclear power, energy savings are paramount and a major component of ongoing sustainable development. Geothermal energy is the energy stored in the form of heat beneath the surface of the Earth. Related to this, the thermal properties of soils are of great importance, particularly with regard to the modern trends of utilizing the subsurface for transmission of either heated fluids or high power currents. For example, in geothermal hydrology or geotechnical engineering applications, the thermal conductivity must be determined to assess the energy potential of the soil. The presence of water (groundwater, rainfall, natural moisture) improves both the thermal conductivity and thermal capacity fields. We present an original method-based on a thermal study and the use of non-integer order models-to determine the thermophysical parameters of different soils in near-surface layers, and link them to the water content variations of different soils. The results are compared with those obtained using a capacitive profile probe. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4737138]