Doped bentonitic grouts for implementing performances of low-enthalpy geothermal systems

Background Energy is a fundamental condition for the social growth of the community, being an essential ingredient for almost all human activities and services. During the past decade, the energy policy has been working towards more environmental-friendly renewable power plants in order to achieve maximum advantages and/or fewer impacts from the exploitation of fossil-fuel resources (Kalaiselvam and Parameshwaran 2014). Efforts have been concentrated mainly in the field of applied solar and wind energy (generally promoted by many subventions), and geothermal energy played comparatively a less prominent role among renewable sources. Although anomalous geothermal fluxes useful for exploitation are present in specific geological settings, there is a worldwide incredible potential related to low-enthalpy geothermal energy that is, at present, scarcely considered in many countries (Banks 2012 and references therein). In this regard, primary reasons are the lack of scientific-technical background in the field of low-enthalpy geothermal resources, coupled with the absence of adequate basic information of Abstract