Designing of a solar-powered cathodic protection system for a ~50 km long buried natural gas pipeline located in Sindh, Pakistan

Corrosion leaks are of significant concern to global oil and gas industry. It is considered as the largest controllable factor in pipeline safety. Cathodic protection (CP) is an electrical method for preventing corrosion and it is the most practical method for such prevention. It is difficult and expensive to install conventional power lines in remote area for power supply of CP systems. Currently (in 2003), oil and gas exploration companies in Pakistan are using thermal electrical generators for powering CP system, which is also an expensive method. In this regard, powering CP systems by using renewable energy for remote location is an attractive option, which was thoroughly analysed in this project. Solar powered CP systems are considered to be economical for remote locations, especially due to their less maintenance requirements and very high reliability. This option has not been yet employed by any oil and gas exploration company in Pakistan. The main objective of this project was: 1) to develop a solar powered CP system for main gas pipeline (51.4 kms) of Sara/ Suri gas field, Tullow Pakistan Developments Limited, Dharki, Sindh (Pakistan); and 2) comprehensive corrosion analysis of the soil.