The National Natural Gas Transmission Network (RNTGN) is the infrastructure for transporting gas on the National Natural Gas System and consists of a network of gas pipelines of around 1,300 km in length with diameters varying from 12” to 32” (inches). Also comprising the RNTGN are stations of the following types:
Junction stations for pipeline branching
Block valve stations, whose main function is to switch pipelines in emergency situations
Gas regulation and metering stations for reducing pressure and metering the gas delivered to consumers who are directly connected to the RNTGN or to distribution networks
Custody transfer stations, which allow the reception and delivery of natural gas on the borders of the RNTGN with the interconnected network
The RNTGN is operated by REN-Gasodutos, S.A., which carries out this work under the public service concession regime, in addition to its activity of Overall Technical Management.
Natural gas is partially odourized at entries through Campo Maior and Valença do Minho. The level of the odorant agent is complemented at consumption exits up to the limits defined by law. The quality control of gas transported and delivered by the RNTGN is carried out by real time monitoring of the most relevant quality parameters (such as Gross Calorific Value, density, Wobbe Index and composition of the natural gas) through the use of gas and sulphur chromatographs installed at specific points in the transmission network.