Patent ID: 8056623

Claim:
A subsurface formation monitoring system comprising: a conductive piping structure positioned within a borehole extending into a subsurface formation; a production tubing disposed inside the conductive piping structure; an insulating packer electrically decoupling the production tubing and the conductive piping structure; a surface installed power and communication module coupled to a grounded return electrode coupled to the subsurface formation; a downhole installed conductive casing sub coupled to the conductive piping structure and comprising at least one sensor mounted on the downhole installed conductive casing sub; and a downhole intermediate module connected to the surface installed power communication module and coupled to the conductive piping structure so as to couple the surface installed power and communication module and the conductive piping structure; wherein the surface installed power and communication module comprises an alternate current generator to define an ingoing signal path along the conductive piping structure and the downhole installed conductive casing sub, the ingoing signal flowing from the surface installed power and communication module to the conductive piping structure via the downhole intermediate module and then to the downhole installed conductive casing sub, the ingoing signal transmitting power from the alternate current generator to the downhole intermediate module and to the at least one sensor via the downhole installed conductive casing sub; and wherein a return signal comprising sensor measurements is transmitted through a return signal path from the downhole installed conductive casing sub to the surface installed power and communication module via the grounded return electrode.