Patent ID: 8881806

Claim:
A system for treating a subsurface formation, comprising: a wellbore at least partially located in a hydrocarbon containing formation, the wellbore comprising a substantially vertical portion and at least two substantially horizontal or inclined portions coupled to the vertical portion; a single, first elongated conductor extending continuously along a length of a first of the two substantially horizontal or inclined portions of the wellbore, wherein the first elongated conductor comprises electrically conductive material along a length of the first elongated conductor; a single, second elongated conductor extending continuously along a length of a second of the two substantially horizontal or inclined portions of the wellbore, wherein the second elongated conductor comprises electrically conductive material along a length of the second elongated conductor, and wherein at least a portion of the first elongated conductor and at least a portion of the second elongated conductor are vertically displaced in the formation; wherein the first elongated conductor and the second elongated conductor comprise substantially vertical portions positioned adjacent and non-concentric in the substantially vertical portion of the wellbore with current flow in the substantially vertical portion of the first elongated conductor approximately equal and opposite to current flow in the substantially vertical portion of the second elongated conductor; and a power supply coupled to at least the first conductor, the power supply configured to electrically excite the electrically conductive materials of the first elongated conductor such that current flows between the electrically conductive materials in the first elongated conductor, through at least a portion of the formation, to the electrically conductive materials in the second elongated conductor, and the current resistively heats at least a portion of the formation between the two substantially horizontally oriented or inclined portions of the wellbore.