SAInt - A Simulation Tool for analyzing the Consequences of Natural Gas Supply Disruptions

The interruption of gas supply to the EU through Ukraine in January 2009 has been the largest gas crises in the EU ever. This was the triggering event to develop and finally enact Regulation 994/2010 on security of gas supply, nowadays of mandatory implementation by EU Member States (MS). According to this Regulation, MS have to develop a Risk Assessment (RA), a Preventive Action Plan (PAP) and an Emergency Plan (EP), among other obligations. The development of a RA needs the identification of a number of scenarios, and the estimation of their probabilities and consequences. In this paper, we focus our effort on the correct estimation of consequences of potential scenarios. Given the complex and dynamic behavior of national or regional gas transport systems (GTS), this estimation can only be done with an adequate gas transport network simulation model. In previous work, a mathematical engine (SAInt) was developed for simulating hydraulic transients in GTS under isothermal conditions. Nevertheless, the actual resolution of transport equations is not sufficient to simulate the degrees of freedom of a network to react to a transient or, more severe, to a gas supply disruption. In this paper, we identify the different actions that the operator, market actors and authorities may adopt in the different steps of a gas crisis and the infrastructure elements used to implement those actions (production sites - PRO, underground gas storage facilities - UGS, liquefied natural gas regasification terminals - LNG, compressor stations – CS, cross border entry points - CBE, etc.). Furthermore, we identify the different possible control modes of each facility in the gas infrastructure and implement them in SAInt to further develop its capabilities as an integrated simulation tool to analyze gas supply disruptions. Finally, we apply SAInt on a real world instance