Overview Natural gas imports to Europe will increase with a constant annual rate of 4,5% due to both the reduction of internal production and the constant increase in gas demand. As a consequence the total amount of gas to be imported to Europe in 2025 is forecasted to be around 600 bcm, doubling the current value. This element, supported by the supply diversification that European Union is pursuing, is pushing towards the construction of new regasification terminals leading to an increase of possible gas suppliers.
Gas is imported into Europe by two ways: through pipeline in gaseous form or alternatively by LNG supply chain, it is liquefied, transported in vessels and finally regassified in Europe. These two chains differ not only from the physical and economical point of view, but also from the environmental one. In order to transport the gas from the production fields to Europe, energy is required and its overall amount differs according to the way and the path the gas is imported. Furthermore other factors, like methane fugitives and nitrous oxide emissions, are affected not only by the physical characteristics of the chain, but also from the technology used and from obsolescence of installations.
The aim of this paper is to analyse from the environmental and economical point of view the global impact of the gas that enters into Europe, investigating the contribution of all the chain steps, starting from the production of the gas until the consumption in a “combined cycle gas turbine” (CCGT) plant for power generation.
Six different real cases are studied: three regard a pipeline-based transport and three regard LNG production, transport through tankers and regasification. These six real cases are compared to the GHG emissions of a reference case: power generated in a CCGT plant in North Africa and imported to Europe.
The six cases studied are:
Case A1: gas production in the Yamburg and Urengoj fields (Russia), transport through Central and Northern Corridor pipelines and consumption in Germany
Case A3: gas production in Krechba, Teg and Reg fields (Algeria), transport through Maghreb Europe Pipeline and consumption in Spain
Case B1: gas production in West Delta Deep Marine (Scarab and Saffron fields) concession (Egypt), liquefaction in Segas LNG plant (Egypt), regasification in Panigaglia (GNL Italia) and consumption in Italy
Case B2: gas production in North field (Qatar), liquefaction in Qatargas 2 LNG plant, regasification in Adriatic LNG plant and consumption in Italy
Case B3: gas production in Dolphin field (Trinidad and Tobago), liquefaction in Atlantic LNG plant (Trinidad), regasification in Bahia de Bizkaia (Bilbao) and consumption in Spain
The study encopasses five steps:
Definition of the main current and future European gas suppliers. This activity deals with: analysis of the current gas/LNG flows, analysis of the supply contracts, development of new import and export infrastructures.
Set up of six different scenarios of supply, on the base of the analysis of the step 1. Three cases are based on pipeline transport and three on LNG production, transport through vessels and regasification, as presented in the figure 1.
GHG’s emissions analysis of the six different gas chains, considering for each part of the chain: fuel consumption (and resulting CO2, methane and NOx emissions), natural gas venting from leakages, CO2 venting (e.g. for natural gas sweetening in the treatment facilities), gas flaring. This data are calculated by taking into account: efficiency of technologies in the different chain steps, site specific characteristics of the production fields (e.g. CO2 content in the raw gas), transport distance and type of gas chain (LNG or pipeline).
Analysis of the results and comparison of the six scenarios from the environmental point of view (energy consumption, GHG emissions).
Economical comparison of the six cases in order to underline the gas supply cost as a function of the distance among the production field and the European border.