Prospects for Enhanced Single-Well Heat Extraction

Abstract

Higher temperature fluid from a single well viewed as a thermal-conduction-bound heat pump may be possible by enhancing near-wellbore permeability to allow a greater effective wellbore radius. Heat advection simulation in 2D estimates the degree to which increased permeability about a wellbore can be expected to increase single well heat productivity. We find that for representative circumstances, heat extraction via wellbore-vicinity advective flow could increase recovered fluid temperature to ~200oC from ~100oC available via a thermal conduction-based heat pump. Prospects for higher heat extraction through enhanced in situ flow in the vicinity of a wellbore - possibly through thermal shock but also through in situ fluid pressurisation - could underwrite scientific and/or engineering investigations directed to larger questions posed by EGS.