Abstract: In at least some embodiments, a high-voltage drilling system includes a a power supply to output high-voltage power to an electrical conductor, a bit that extends a borehole based on the high-voltage power, and a hybrid drillstring that transports a fluid flow from the bit to convey detached formation material out of the borehole. At least part of the electrical conductor resides within the hybrid drillstring to convey power to the bit. The hybrid drillstring includes a coiled tubing section and a jointed pipe section.

Abstract: In at least some embodiments, a high-voltage drilling system includes a a power supply to output high-voltage power to an electrical conductor, a bit that extends a borehole based on the high-voltage power, and a hybrid drillstring that transports a fluid flow from the bit to convey detached formation material out of the borehole. At least part of the electrical conductor resides within the hybrid drillstring to convey power to the bit. The hybrid drillstring includes a coiled tubing section and a jointed pipe section.

Abstract: In at least some embodiments, a high-voltage drilling system includes a power supply to output high-voltage power to an electrical conductor, a bit that extends a borehole based on the high-voltage power, and a hybrid drillstring that transports a fluid flow from the bit to convey detached formation material out of the borehole. At least part of the electrical conductor resides within the hybrid drillstring to convey power to the bit. The hybrid drillstring includes a coiled tubing section and a jointed pipe section.

Abstract: In a pulsed-electric drilling system, a nonrotating bit is given a noncircular shape to drill a correspondingly-shaped borehole, e.g., triangular, rectangular, polygonal, oval, or a more complex shape. Some embodiments employ a reconfigurable bit that deploys extensions as needed to dynamically vary the cross-section of the borehole at selected locations. In this fashion, a driller is able to create borehole with a preferred cross-sectional shape to, e.g., drill the smallest possible hole while simultaneously providing additional clearance for equipment or instrumentation, additional surface area for well inflow, channels for improved borehole cleaning, teeth for improved cementing, reduced contact area to reduce drag on the drillstring, or any other benefits achievable by customizing the borehole cross-section.

Abstract: In a pulsed-electric drilling system, a nonrotating bit is given a noncircular shape to drill a correspondingly-shaped borehole, e.g., triangular, rectangular, polygonal, oval, or a more complex shape. Some embodiments employ a reconfigurable bit that deploys extensions as needed to dynamically vary the cross-section of the borehole at selected locations. In this fashion, a driller is able to create borehole with a preferred cross-sectional shape to, e.g., drill the smallest possible hole while simultaneously providing additional clearance for equipment or instrumentation, additional surface area for well inflow, channels for improved borehole cleaning, teeth for improved cementing, reduced contact area to reduce drag on the drillstring, or any other benefits achievable by customizing the borehole cross-section.