Abstract: Precise information and navigation monitoring in horizontal drilling is of great importance for oil exploration and deposit discovery. The cost of the drilling process depends significantly on drilling precision. The necessary drilling accuracy is provided by navigation and information-gathering instruments which need electrical power in order to operate. Small available volume, long drilling times, vibrations, and high temperatures are typical constraints for any power supply source used in downhole drilling. Downhole navigation and information-gatheringsystems become increasingly complex, with more strict demands for the parameters of their electrical power supply. Batteries and conventional power cables are the traditional and the most utilized power supply sources downhole. Both have significant disadvantages and increase the cost of drilling operations. Short lifespan of the batteries and high susceptibility to failure of the cables in the harsh downhole environment are the main motivators for further research in self-sustaining energy sources. Ideally, downhole navigation instruments and information-gathering sensors (e.g. pressure, temperature, etc.) need autonomous power supply with electrical energy produced in situ. This would improve significantly the efficacy of the entire drilling process. This article presents a review of the existing and the emerging concepts related to utilizing the available energy sources in downhole drilling. The advantages and the drawbacks of these energy-harvesting concepts are discussed and compared to conventional power sources. Progress in the development of some of these concepts is illustrated by industrial examples. Some fairly new approaches to electrical energy supply for the information exchange downhole are also presented in order to inspire non-traditional research in this field.

Keywords: Energy harvesting, Horizontal drilling processes, Oilfield Instrumentation, Measurement-While-? Drilling.

ACM Classification Keywords: A.0 General Literature - Conference proceedings; J.2 Physical Sciences and Engineering

Link:

ENERGY HARVESTING IN HORIZONTAL DRILLING PROCESSES FOR THE PURPOSE OF INFORMATION AND NAVIGATION MONITORING

Marian Dimanchev and Martin P. Mintchev

http://www.foibg.com/ijita/vol20/ijita20-02-p11.pdf