European ability to cope with a gas crisis. Comparison between 2009 and 2014

Energy Policy 97 (2016) 461–474

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Energy Policy journal homepage: www.elsevier.com/locate/enpol

European ability to cope with a gas crisis. Comparison between 2009 and 2014 Nuria Rodríguez-Gómez n, Nicola Zaccarelli, Ricardo Bolado-Lavín European Commission – DG-Joint Research Centre, Directorate for Energy, Transport and Climate, Westerduinweg, 3, NL-1755 LE Petten, The Netherlands

H I G H L I G H T S







We analyse the improvements in the EU gas infrastructure between 2009 and 2014. A model of the EU gas grid is used to study the disruption of the major importers. We find that Europe has greatly improved its ability to cope with a gas disruption. We find that Eastern Europe, though enhanced, remains the most vulnerable area.

art ic l e i nf o

a b s t r a c t

Article history: Received 2 February 2016 Received in revised form 14 June 2016 Accepted 11 July 2016

Regulation (EU) No 994/2010 concerning measures to safeguard security of gas supply was adopted following the 2009 commercial dispute between Ukraine and Russia which yield to a gas disruption. Since then, new infrastructure and cooperation measures have being implemented in order to reinforce the European gas system to better cope with gas shortages. Joint Research Centre has developed GEMFLOW, a country-based model of the European gas network, to simulate gas disruptions of different duration and to estimate the survival time and gas non-served per country. In this paper an analysis and comparison of the improvements carried out in the European gas system between 2009 and 2014 is presented and GEMFLOW model is used to evaluate the progress being made to strengthen the security of gas supply at European level. & 2016 Elsevier Ltd. All rights reserved.

Keywords: Gas modelling Natural gas crisis Security of supply Regulation (EU) No 994/2010

1. Introduction Regulation (EU) No 994/2010 (European Union, 2009d) concerning measures to safeguard security of gas supply was adopted following the 2009 natural gas crisis, which showed important weaknesses of the European high pressure transmission system. It repealed and replaced Directive 2004/67/EC (European Union, 2004) on measures to safeguard security of natural gas supply by providing a consistent framework to carry out a full risk assessment of national grids, identifying tools and criteria to improve performances and resilience, and providing means to increase preparedness and skills to cope with crisis. The lesson learnt from the implementation of Directive 2004/67/EC had shown that it was necessary to harmonise national measures in order to ensure that all Member States (MS) are prepared at least on a common minimum level. It was felt that, if all Member States were to n

Corresponding author. E-mail addresses: [email protected] (N. Rodríguez-Gómez), [email protected] (N. Zaccarelli), [email protected] (R. Bolado-Lavín). http://dx.doi.org/10.1016/j.enpol.2016.07.016 0301-4215/& 2016 Elsevier Ltd. All rights reserved.

comply with minimum standards, this would enhance solidarity between them in case of crisis, since no one could be seen “to take a free ride” on the efforts made by others. At the same time, the legislator considered that excessive protection of own gas consumers in some Member States could leave consumers in other Member States more exposed or could disproportionally restrict trade. During the 2009 gas supply crisis the necessary amounts of gas were available on the EU internal market but it was physically impossible to ship them to the affected Member States in Eastern Europe. Against this background, Regulation (EU) No 994/2010 aims to improve cross-border capacities by pursuing the development of new infrastructure which may not necessarily be commercially feasible but is essential in terms of security of supply. The two tools chosen are the implementation of the so-called N-1 rule and the implementation of permanent bi-directional capacity (physical “reverse flows”) (European Commission, 2014a). On 28 May22.9 2014 the Commission adopted its European Energy Security Strategy providing a comprehensive plan to strengthen the security of energy supply in Europe (European Commission, 2014c). A common European strategy, along with a

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Nomenclature Bcm CONS JRC H-gas EU EXP IMP

Billion cubic metre Gas consumption of a country Directorate General Joint Research Centre of the European Commission High calorific gas European Union Gas flow exported in a country Gas flow imported in a country

common European Energy Market – as it has been reinforced by the adoption by the European Commission on 21 September 2009 of the third package of legislative proposals for electricity and gas markets (European Union, 2009a, 2009b, 2009c) – is more and more a fundamental need for the European Union in light of the role played by natural gas in the European energy mix, as the share of natural gas in the European final energy consumption is still slowly increasing, moving from 21.8% in 2009 to 22,9% in 2013.1 Furthermore, to meet the ambitious targets of the 2020 Climate and Energy Package2 and live up to the objectives of the 2030 Framework for Climate and Energy Policies (i.e., the European Council endorsed a binding EU target of an at least 40% domestic reduction in greenhouse gas emissions by 2030 compared to 1990) (European Council, 2014), greater investments in the energy infrastructure will be required in the near future in all the sectors that make up Europe’s energy market. New investments in energy infrastructure across the Union are also instrumental in ensuring integrated and efficient internal energy market and security of energy supply. For all the above reasons, we aim with this paper at providing a first analysis of the effects and improvements put in place by Member States and Transmission System Operators (TSOs) after the enforcement of Regulation (EU) No 994/2010. We provide first a description of the changes in the national infrastructure, and then we start with a comparison of the behaviour of the European grid under four crisis scenarios for 2009 and 2014 by using the “Gas EMergency FLOW” simulator model (GEMFLOW) (Szikszai and Monforti, 2011; Zaccarelli et al., 2014).

2. Improvements in the EU gas infrastructure between 2009 and 2014 This section aims at describing the general improvements developed in the European gas physical infrastructure on the grounds of Regulation (EU) No 994/2010. Within this context, the analysis is focused on assessing and comparing the status of the European natural gas system in 2009 and 2014 in five strategic areas such as length and compression power of the national gas systems, liquefied natural gas (LNG), underground storage (UGS), cross-border capacity and physical reverse flow. It has been intentionally avoided presenting any discussion concerning economic aspects like changes in gas market liquidity or how the gas value chain has been transformed along with the general business model, though it is recognised the relevance of

L-gas LNG Mcm MS PROD STO TSO UGS

Low calorific gas Aggregated send-out flow of all the regasification terminals of a country Million cubic metre Member State Aggregated production flow of a country Aggregated withdrawal flow of the underground storages of a country Gas Transmission System Operator Underground Storage facility

such topics for a mature and well-shaped Energy Union.3 Furthermore, it is not addressed here the positive implications of the Regulation (EU) No 715/2009 (European Union, 2009c) to enhance market transparency and to facilitate access to information for network users and market participants. Although it should be noted that 86% European Transmission System Operators fully comply with the requirements of the Regulation (ACER, 2013), which it has enormously facilitated the study carried out in this paper thanks to the ad-hoc web-based platform for transparency and data dissemination created by ENTSO-G4 under the umbrella of Regulation (EU) No 715/2009. 2.1. Pipelines and compression power Besides the comparison of the gas facilities a simple comparison of two key indicators of the structure of the high pressure grid of a Member State (MS) is carried out to offer a more complete picture of the complex interaction and feedbacks among the components of the integrated European gas grid. The first indicator, the total length of the grid, would provide an idea of how investments were translated into a better connection from sources to customers to increase volumes, distribution and generally the resilience of the network. The second, the total installed compression power, could give a further indication of the increase capacity and commitment to implement bidirectional flows. The general picture depicted in Table 1 shows how, with some remarkable differences between MS, the EU high pressure grid has grown 8% in length of pipelines and 14% in total compression installed power, to better address issues related to increase interconnectivity (within and between MS) and volumes (i.e higher capacity to move gas). The role as pivotal actors of some MS, like Germany and the Netherlands, is marked by relevant changes in the two indicators, while other MS, in particular from Eastern Europe and the Baltics, show less relevant improvements. 2.2. LNG facilities The European LNG market has been characterised by a substantial reduction since 2011 (see Fig. 1) due to a combination of factors such as a general decrease in demand (linked to relatively mild weather conditions and the economic crisis), competition with other markets (mainly the far East markets), cheaper prices for natural gas from pipelines (with Russian origin in first place) and competition with other fuels in the power generation sector. Demand in Europe fell to 34.3 Bcm in 2014 (GIILNG, 2009–2013), accounting for 8.5% reduction compared to 2013. This is the third year of a decline in LNG demand and overall demand is 42.5% lower than in 2009.

1

EUROSTAT, 2015. The 2020 Climate and Energy Package sets three key objectives: (i) 20% reduction in EU greenhouse gas emissions from 1990 levels; (ii) raising the share of EU energy consumption produced from renewable resources to 20%; (iii) a 20% improvement in the EU’s energy efficiency. 2

3 The EU’s Energy Union strategy is made up of 5 closely related and mutually reinforcing dimensions: supply security, a fully-integrated internal energy market, energy efficiency, climate action and research and innovation. 4 https://transparency.entsog.eu/

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Table 1 Total length of high pressure transmission and transit systems and total power of compressor stations by Member States in 2010 and 2014.Source: JRC analysis on GRIP 2014–2023, ENTSO-G TYDP 2011–2022 and TSO web-sites. Total length (km)

Total installed power in Compressor Stations (MW)

Austria Belgium Bulgaria Croatia Czech Republic Denmark Estonia Finland France Germany Greece Hungary Ireland Italy Latvia Lithuania Luxemburg Poland Portugal Romania Slovakia Slovenia Spain Sweden Netherlands United Kingdom Total

2010

2014

%’14 –‘10 2010

2014

%’14 –‘10

1600* 3900 2645 2085 3643 800 877 1186 36,617 31,515 1218 5564 2368 33,584 1281 1865 411 9777 1299 13,110 2270 1018 9984 620 11,650 7880 188,767

1600 4100 2645 2662 3813 953 885 1314 37,156 38,125 1291 5784 2467 34,415 1240 2007 413 10,077 1374 13,138 2367 1094 10,512 620 15,500 7880* 203,432

0% 5% 0% 28% 5% 19% 1% 11% 1% 21% 6% 4% 4% 2% -3% 8% 0% 3% 6% 0% 4% 7% 5% 0% 33% 0% 8%

621 116* 263 – 297 18,3 – 64 636 2542 13 233 94 867 – 42 – 150* – 32 700 16 526 – 808 1611* 9631

13% 0% 0%

551 116 263 – 297 – – 63 643 1679 – 188 94 857 – 42 – 150 – 30 700* 16 413 – 734 1611 8447

0% þ 2% -1% 51% þ 24% 0% 1% 0% 0% 7% 0% 0% 27% 10% 0% 14%

 No compressor station exists. þ New compressor station after 2009 * The value has been assumed equal to the other reference year for lack of information publicly available.

Fig. 1. Evolution of LNG imports – net of re-exports – in EU from 2009 to 2014 in billion cubic metres of liquefied natural gas in gaseous form (Source: GIILNG, 2010, 2015.).

This recent market contraction is not reflected in the strategic role of LNG in the EU policy. The recent adoption of the “European Energy Security Strategy” (European Commission, 2014c) pointed to EU strong dependence from a single external supplier (i.e., Russia) and identified LNG as a relevant tool to diversify sources of gas. Together with this argument, LNG has been identified as one of the most efficient answers to short-term crisis or shocks, along with the use of UGS (European Commission, 2014b). The number of regasification plants has increased of four units, from 17 to 21 in 2014, after the coming into operation of two

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Floating Storage and Regasification Units (FSRU), one in Italy and one Lithuania, and two on-shore plants, one in the Netherlands and one in France. The nominal annual aggregated send-out capacity increased by 41% from 134 to 189 Bcm/y, as a combination of the new facilities and the upgrading of existing facilities (e.g., the United Kingdom showed an increase of 65%, Table 2). The maximum daily aggregated send-out capacity is further increased from 483.5 to 616.5 Mcm/d, so providing an extra 28% capacity over five years. 2.3. Underground storage facilities Underground gas storage facilities (UGS) play a key role as a balancing tool in the event of a supply disruption in EU (European Commission, 2014b). UGS can act as a buffer in case of a disruption of gas deliveries however the volume availability of natural gas depends on storage level inventories and the withdrawal rate with which gas can be delivered to the consumers. According to Gas Infrastructure Europe5 there were 143 UGS facilities in Europe in 2014, with an increase of 11% since 2009, comprising a combined working volume of 100 Bcm (an increase of 21% since 2009) (see Table 2). The majority of the facilities and the greatest share of working gas are in Central-West of Europe (i.e., Germany with 55 facilities, Italy with 10 and France with 15; see Fig. 2) where the domestic demand is among the highest in Europe. Other countries, like Austria (with 9 facilities) and Latvia (1 facility), show high values of working volume because the UGS plays a role also at the regional level: Austria supports the German market while Latvia provides service to Estonia, Lithuania and Russia. By comparing 2009 and 2014 storage figures (GIE, 2009; GIE, 2014b), EU shows a marked increase in withdrawal capacity of 23.5% (up to 2030 Mcm/d) and injection capacity of 33.3% (up to 1122 Mcm/d), with approximately three quarter of the facilities providing access through a negotiated regime. Austria, Hungary and Poland showed higher increased of working volume (93%, 70% and 60% respectively) followed by Portugal and Bulgaria (with 59% and 57%) (See Table 2). The increase in the national aggregated withdrawal capacity follows the same pattern, with the exception of a marked increase of Spain which has actually more than doubled from 14.8 Mcm/d to 31.5 Mcm/d. Average withdrawal capacity (i.e., aggregated withdrawal capacity at national level divided by the number of UGS facilities) is unevenly distributed among MS, with the Netherlands, Italy and Latvia showing the higher figures both in 2009 and 2014. However, the business model for filling gas storages is not necessarily setting incentives to store gas to prevent crisis situations. Gas storages are being filled in on the basis of spreads between summer and winter time. Analysis of such spreads, based on historic events does not predict unexpected events. Moreover the price spread between winter time and summer time decreases over years. The decreasing spreads and volatility (due to a combination of factors such as excess of supply in Europe), competition from other sources of flexibility (LNG, interconnectors and spot gas) and increasing storage-to-storage competition have undermined the value of storage. In addition the recent communication on the preparedness for a possible disruption of supplies from the East during the fall and winter of 2014/2015 (European Commission, 2014b) has showed that the way MS address the use of storages may hide important risks for the security of supply in the medium term because where countries rely on a short term increase in withdrawal rates (unless measures are taken subsequently to avoid emptying storages too rapidly), these countries have to face the repercussions later in case the disruption or 5

http://www.gie.eu/index.php/maps-data/gse-storage-map

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Table 2 Percentage of change between 2009 and 2014 (2013 when *) in LNG nominal aggregated and send-out capacity, storage capacity, production capacity and consumption. Source: ENTSO-G 2009–2014. IEA, Natural gas Information, Ed. 2010 and Ed. 2014. Percentage of change between 2009 and 2014 LNG nominal aggregated capacity LNG maximum aggregated send-out capacity Gas storage working volume Production capacity* Consumption Austria Belgium Bulgaria Croatia Czech Rep. Denmark Estonia Finland France Germany Greece Hungary Ireland Italy Latvia Lithuania Luxemburg Netherlands Poland Portugal Romania Slovakia Slovenia Spain Sweden United Kingdom Total

– 0% – – – – – – 40% – – – – 35% – – – – – 44% – – – 11% – 65% 41%

– 0% – – – – – – 42% – þ – – 38% – – – þ – 50% – – – 4% – 17% 28%

93% 2% 57% 0% 14% 0% – – 6% 15% – 70% 6% 16% 0% – – 6% 60% 59% 15% 14% – 48% 0% 20% 21%

 18% – 1535%  31% 42%  43% – –  63%  21%  55%  34%  12%  3% – – – 9% 6% –  5% 20% 0% 300% –  38%  13%

 15%  12% 14%*  7%  8%  28%  17%  28%  19%  10%  17%  26%  6%  21% 13%*  1%*  23%  17% 12%  15%  5%  29%  25%  25%  27%  22%  6%

 No facility exits þ New facility after 2009 *

The information for 2014 is missing and the percentage of change is estimated for 2009–2013.

Fig. 2. Aggregated working volume of UGS per country of EU (Source: ENTSO-G, GIE).

problems endures, including that withdrawal rates at low storage levels decrease substantially. 2.4. Cross-border capacity and physical reverse flow Among different tools foreseen by Regulation (EU) No 994/2010 (European Union, 2009d) to increase and strengthen the level of EU security of supply the use of physical bi-directional gas flow6 6 Physical reverse flow stands for the technical and commercial possibility that natural gas is transported in both directions across a certain interconnection point (up to the available technical capacity), independently from the quantity of gas coming from the prevailing forward direction.

(or reverse flow) has a special role. TSOs were obliged by the Regulation to enable permanent bi-directional capacity on all relevant cross border points by 3 December 20137 and Competent Authorities are obliged to regularly check the need for reverse flows when they update their risk assessments and plans. Reverse flow can be an efficient and cost effective way of increasing entry capacity and having access to new sources of gas. It provides a tool to change the direction of traditionally one-way

7 But the Competent Authorities may grant an exemption in case the bi-directional capacity would not significantly enhance the security of supply of any Member State or region, or if the investment costs would significantly outweigh the prospective benefits for security of supply.

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Table 3 Number of cross-border interconnection points in the EU by type of directional gas flow (i.e., unidirectional or bi-directional) in 2009 and 2014a.Source: JRC analysis on GIE and ENTSO-G maps. 2009 2014 Number of bi-directional interconnection points Number of unidirectional interconnection points Total number of cross-border interconnection points in the EU

12 37 49

21 32 53

a The analysis does not take into account low-pressure pipelines which cross the border to serve local demand and which are not part of the high-pressure transmission network and any cross-border interconnection with non EU Member States, with the exception of Switzerland.

transport routes in case one of the Union’s major supplies becomes unavailable and it helps the shippers to rapidly and massively reroute gas deliveries within internal market. Reverse flow has been substantially implemented within the EU as the number of interconnection points increased from 24% in 2009 to 40% in 2014 (see Table 3). The map in Fig. 3 describes the physical bi-directional capacity (i.e., reverse flow) at cross-border interconnection points in the EU between 2009 and 2014, excluding non EU Member States (with the exception of Switzerland), pointing to locations where improvements in the physical bi-directional have taken place. Only physical capacity available from all TSOs at a particular cross-border point is considered. The case of only one country providing physical capacity or backhaul is not covered. The data used to build the map are derived by the

465

analysis of the GTE map for 2009 (GTE, 2009) and the ENTSO-G map for 2014 (GTE, 2014). Data for 2014 have been cross-checked with ENTSO-G, while data for 2009 have been cross-checked with TSOs and other data sources. Thanks to these improvements, natural gas can flow in both directions via almost every second interconnection point between Member States. Furthermore the geographical location of the new bi-directional interconnections provides insights on an increase flexibility of moving natural gas among MS and directions like North-South (Denmark-Germany, Austria-Italy, Greece-Bulgaria and Romania-Hungary) (European Commission, 2014a) or EastWest (Germany-Poland, France-Spain, Austria-Slovakia). All these improvements can certainly be regarded as an important success, though some strategic elements (like the cross-border interconnection between France and Germany at Obergailbach, Waidhaus interconnection between Germany and Czech Republic, or the BBL pipeline connecting United Kingdom and the Netherlands) are still far from implementing bi-directional flows. As it has been clearly explained in the Staff Working Document (European Commission, 2014a) that accompanies the document (European Commission, 2014b): “The majority of this development has come from commercial projects incentivized by the market demand. Nevertheless, Regulation 994/2010 has been instrumental in putting in place or speeding up physical reverse flows on some interconnections where voluntary market developments did not bring about the necessary results on time, although reverse flows are crucial for security of supply reasons, such as on the Yamal pipeline between Poland and Germany, on the interconnection between Romania and Hungary and between Greece and Bulgaria."

Fig. 3. Comparison of the physical bi-directional capacity at cross-border interconnection points in the EU between 2009 and 2014, excluding non EU Member States (with the exception of Switzerland).

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For the majority of interconnection points which were unidirectional since 2009 (Fig. 3) an “exemption” granted by the Competent Authorities is the reason. Exemptions were granted for different reasons like:


the interconnection links a Member State at the end of the





supply route (cul-de-sac) with no possibility of having gas that could be shipped in the reverse direction(e.g. through UGS), or the connection is directly linked to a distribution network or a production field; different odorization practices on both sides of the border prevent technically the reverse flow; unnecessary to make investments for ensuring reverse flows of L-gas into areas where L-gas may be supplied by blending H-gas.

Along with the implementation of physical bi-directional capacity among MS, the overall capacity of the EU high pressure grid has improved as a whole of 8,6% since 2009. The improvements in capacity at cross-border stations between 2009 and 2014 can be seen in the map of Fig. 4 which describes the aggregated crossborder capacity by country. The capacities haven been derived by the analysis of the ENTSO-G maps for “capacities at cross-border points” for 2009 (GTE, 2009) and 2014 (GTE, 2014). Along with some new interconnections and associated capacity (like in the case of Romania-Hungary and Hungary-Croatia), some MS have increased their capacity of moving gas substantially like Germany,

Austria, the Netherlands and Belgium (see Fig. 4). Capacity at international cross-border interconnection with no EU MS has shown as well a remarkable increase like with Norway (25% since 2009), with Northern Africa (32% mainly due to Almeria cross-border point), and from Russia directly through Nord Stream or indirectly through Belarus (i.e., Jamal pipeline) or Ukraine (15,8% since 2009) (Table 4). This increment in capacity and number of supply routes is not yet enough to relieve certain regions of Europe of their dependency on a single supplier, like for instance the Baltic or the South-Eastern region.

3. GEMFLOW, a mass-balance model of the European gas system The “Gas Emergency FLOW” model (GEMFLOW) is one of the technical tools developed by JRC to investigate gas emergency crisis at EU level (Szikszai and Monforti, 2011; Zaccarelli et al., 2014). GEMFLOW is a model coupling a Monte Carlo simulation approach within a framework of rules created to describe the behaviour of the EU gas system during a crisis. The model is s built using the language of technical computing MatLab from s MathWorks . Several regional or pan-european models have been developed by public or private research Institutes or Agencies, like NATGAS by CPB Netherlands Bureau for Economic Policy Analysis (Mulder and Zwart, 2006), GASMOD by Deutsches Institut für

Fig. 4. Aggregated cross-border capacity by country as derived by the analysis of the maps for “capacities at cross-border points” by GTE for 2009 and by ENTSO-G for 2014 excluding non EU Member States (with the exception of Switzerland).

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Table 4 Capacity at the interconnection points within Europe and among Europe and Norway, Northern Africa, Russia, Belarus and Ukraine, and other Countries (i.e., FYROM, Serbia, Bosnia Herzegovina and Turkey)a.Source: JRC analysis on GIE and ENTSO-G maps. 2009 Aggregated capacity at cross-border the EUb Aggregated capacity at cross-border Norway Aggregated capacity at cross-border Northern Africa Aggregated capacity at cross-border Russia, Belarus and Ukraine Aggregated capacity at cross-border other Countries

2014

% 09– 14

points within 1860,9 2020,2 8,6 points from

335,0

418,8

25,0

points from

144,7

191,0

32,0

points from

643,0

744,9

15,8

points from

63,7

62,9

-1,3

a Figures were derived using the provided gross calorific value or if missing a reference value of 11,18 b And Switzerland.

Wirtschaftsforschung (DIW) (Holz et al., 2008), GASTALE by the Energy research Centre of the Netherlands (Boots et al., 2003), and TIGER by Energiewirtschaftliches Institut of the University of Cologne (EWI) (Lochner and Bothe, 2007). All these models are mainly developed to describe the behaviour of a competitive natural gas market to analyse the effects of liberalisation or investment in infrastructures within the EU. Other models have been primarely developed to investigate congestion and optimal congestion strategies. Lochner (2011) used a network model to identify bottlenecks and evaluate transport capacities and cost of congestion based on nodal prices. Dieckhöner et al. (2013) analysed a variety of scenarios with a detailed European natural gas infrastructure model to analyse gas flows and identify where and when congestions occur in the European natural gas transmission network. Carvalho et al. (2014) used an EU network model for

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natural gas to investigate resilient response strategy to energy shortages to handle network congestion on various geographical scales. However, GEMFLOW has been primarily designed for assessing security of supply implications of natural gas disruptions or crises by exploiting cooperation and solidarity mechanisms among EU countries. For this reason no market or economic constraints on gas flows are considered. GEMFLOW is a mass-balance network model which includes 30 countries which are defined as European countries (26 EU MS which are gas consumers plus Switzerland, Bosnia, Serbia and Former Yugoslav Republic of Macedonia (FYROM)). Other 9 countries are described as gas supplier or gas transit to Europe, these are Algeria, Belarus, Libya, Morocco, Norway, Russia, Tunisia, Turkey and Ukraine. Each country is defined as a node and it is connected to a neighbouring country through a single virtual pipeline that sums up the capacity of all the real pipelines that actually connect the two countries (see Fig. 5). The capacity of the virtual pipeline establishes the upper limit of gas that can be transported between countries. Each country is defined with 4 flow variables: domestic production (PROD), storage withdrawal flow (STO), regasification flow (LNG) and domestic consumption (CONS). The gas flow imported (IMP) and exported (EXP) is the result of the aggregation of all the gas flowing in and out of the country via pipeline. GEMFLOW aims at reaching the balance in the 30 European countries at any moment. A country i is balanced when the following equation is fulfilled:

PRODi +STOi +LNGi −CONSi+IMPi−EXPi=0

(1)

If the result of the equation is lower than zero, the country will be unbalanced and therefore it will be unable to satisfy the demand. The countries with a balance lower than zero are in-need countries. The countries which have a balance higher than zero are gas provider countries and will send their spare gas to in-need countries according to the interconnectivity between them.

Fig. 5. Flow map that represents the configuration of gas interconnections in GEMFLOW model.

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The model can simulate gas disruptions by decreasing the values of production, storage, regasification flow or the gas imported from one or several countries. GEMFLOW can also simulate the effect of an incremented gas demand by increasing the value of gas consumption in one or more countries. The duration of the scenario simulated is a variable to be decided by the user. It can be simulated a one-day case or a 3 months case (90 days). However, it must be born in mind that the initial value of the variable CONS (consumption) defined in Eq. (1) is not changed during the simulation. It means that if a 30 days case is simulated it is assumed that the consumption of a country remains constant during the whole period. GEMFLOW model implements a Monte Carlo approach8 seeking all EU countries reach the gas balance. The essential idea is to simulate the EU gas system, built up on a specific set of rules, by repeating random sampling of parameters from reference probability distributions. Thus, hundreds or thousands of possible outcomes, each based on a different strategy, are produced. The analysis of the statistical properties of the distribution of the outputs provides insights on the unknown probabilistic entity. Based on such an approach, GEMFLOW does not look for the “optimal” strategy through the minimisation of some indicators but allows the system to evolve freely following the model rules and producing a number of possible strategies to be deployed to face the crisis. In this way (taking account of nearly all possible system operator decisions) it is possible to have a probabilistic picture of the resilience (stability) of the system. The duration of the case study (number of days) and the number of executions or iterations are variables to be decided at the beginning of the simulation. A case study of 30 days with 100 iterations means that the case study of 30 days will be repeated 100 times. The solution obtained at the end of the simulation will show the probability of failure of each country and the average amount of unserved gas per country during the period of the crisis, based on the average results obtained for each one of the iterations. The simulation of a crisis scenario starts with initial values of CONS, PROD, STO, LNG, IMP and EXP per country. Once Eq. (1) is evaluated with the initial data, countries are classified in balanced countries (if the result of Eq. (1) is equal or higher than zero) and un-balanced countries (if the result of Eq. (1) is lower than zero). From this point on, GEMFLOW model will try to find the balance in all countries by means of a three-step strategy. In the first step, the domestic resources of the country in trouble (un-balanced countries) are exploited to try to reach the gas balance. Thus, GEMFLOW will increase, if possible, up to the maximum the production flow (PROD) and the regasification flow (LNG), and will randomise the storage withdrawal flow (STO). The gas consumption of a country (CONS) remains constant during the whole simulation as well as the gas imported (IMP) from a non-EU country. In the second step, if the domestic sources are not sufficient to reach the balance, un-balanced countries try to obtain gas from countries with gas surplus attending always to the limits imposed by the virtual capacity between countries. In this situation, the variable IMP, that represents the aggregated import gas flow of a country, might change to increase the gas entry from EU neighbouring countries and consequently the variable EXP, that represents the gas flow that a country sends to a neighbour, will change accordingly. It may be several possibilities that yield to a solution when deciding up to what extent the domestic resources could be incremented in the first step and when deciding the order and amount of gas in which surplus gas countries could send gas to in8 statistical technique to explore the behaviour and sensitivity of a complex system by manipulating parameters within defined statistical constraints

need countries in the second step. In case that several options are possible, GEMFLOW model will make the selection by randomizing the number of neighbours to provide help and the gas amount provided. In this way there is not a determined strategy that has priority over another. The higher the number of iterations introduced in GEMFLOW are, the bigger the spectrum of solutions obtained is. In the third step, the countries are reclassified into balanced or un-balanced countries. The gas not served in the unbalanced countries is recorded and the inventory of the storage facilities is updated accordingly for the next day of the crisis. Once the three steps are completed, one day of the simulation has occurred. The following days of the crisis will repeat the three step strategy for the entire duration of the case study. GEMFLOW model will repeat the whole case study the number of iterations that the user has set up. Further details about the Monte Carlo approach used by the GEMFLOW model are provided in Szikszai and Monforti (2011). The input data that GEMFLOW model requires to operate are defined by the aggregated technical capacity between countries, the aggregated flow from import countries to Europe and the main gas features of each country (i.e. average consumption, maximum domestic production, maximum regasification capacity, maximum storage withdrawal and maximum volume of storage capacity). The aggregated technical capacity between countries is obtained from Fig. 4 which determines the values for the reference year of the simulation. When a scenario is simulated the values corresponding to the reference year, 2009 or 2014, are used accordingly. The value of capacity establishes the upper limit of gas that can be transfer from one country to another. The aggregated gas flow data from importer countries are extracted from the Monthly Gas Data Service of the IEA.9 When simulating a certain scenario, the values of flow are adjusted consequently to reflect the situation of the month or period being evaluated. The main gas features of each country correspond to the specific month and year that it is being simulated. The values used in the simulation regarding gas production, maximum storage withdrawal and maximum regasification capacity are obtained for 2009 and 2014 reference years from GIE (GIE, 2014a, 2014b) and IEA databases (IEA, 2013, 2014).

4. Performance of the EU gas network during simulated crises A crisis simulation approach was used to carry out the assessment of the behaviour of the high pressure EU natural gas grid and the effects of the changes in the infrastructure between 2009 and 2014. Each scenario is run hundreds of times to allow the settings of the model perform with different possible strategies to tackle the gas disruption. At the end of each run or simulation the results are obtain in statistical terms, thus the use of GEMFLOW model allows the evaluation of the probability of failure, or inability to ensure the gas demand, of a country and the extent of unserved gas to customers as a result of different gas disruptions. The goal of the modelling simulation was to compare the ability of EU as a whole to cope with a major gas disruption happening both in 2009 and 2014. The improvements of gas infrastructures, the adoption of bi-directional capacity together with the decrease of gas consumption in Europe might indicate beforehand that Europe is better equipped to tackle a major gas crisis in 2014 than in 2009. However, in order to establish a fair playfield for the simulations carried out, some assumptions were adopted. The gas consumption values of January are obviously very different of those of July. In general the gas consumption per country 9

https://www.iea.org/statistics/mgds/

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changes every year and, as it was seen in Table 2, the overall EU gas consumption in 2014 decreased 6% respect to 2009. However the decrease in gas demand has not been continuous since 2009. In 2010 the gas consumption increased 8% respect to 2009, (IEA, 2013, 2014) and represents the highest EU gas demand in history. In all simulations carried out, both 2009 and 2014 scenarios, the values of gas consumption corresponding to 2010 are used. In this manner, the impact of new infrastructure is really assessed and the seasonal changes of gas consumption are ignored. The monthly volume of gas in storages is another seasonal factor that varies along the months and may change among the years. For this reason, for all cases studied in this paper the volume of storages has been set at 70% of the maximum working capacity. It means that when the crisis starts the volume in all the EU storage facilities is 70% of the maximum inventory capacity. The regasification capacity has been treated in the same manner. LNG terminals have a maximum send-out capacity that it is somehow related to the size and stock level of the LNG tank. Maintaining a certain stock level in the LNG tank depends in turn on the frequency that ships are received. The regasification terminals are designed to maintain the maximum send-out for at least one day without restrictions however the crises in this study have 30 or 90 days long duration. Bearing in mind the possible limits of a LNG terminal to operate at its maximum send-out capacity during long periods of times, the maximum regasification capacity has been set at a rate of 70% of its real maximum in all scenarios simulated both in 2009 and 2014. The scenarios studied by using GEMFLOW model are based on the disruption of the main gas importers which provide gas to Europe via pipeline. The major importer countries are Russia, which provides 32% of the imported gas, Norway, providing 31%, and Algeria which provides 13% (Statistical Pocketbook, 2014). An interesting country disruption to study is Ukraine since it serves as a transit country transporting about 50% of the Russian gas imports into Europe. Therefore the following scenarios were studied: 1. Reference Scenario (REF): normal operation where no gas disruption occurs. This scenario is run to establish the reference point for crises happening in 2009 and 2014. 2. Ukraine Scenario (UA): total disruption of all gas imports from Russia that come into Europe through Ukraine. 3. Russian Scenario (RUS): total disruption of all gas imports into Europe coming from Russia (included all flows of natural gas in transit through Ukraine, Belarus and Nord Stream pipeline to Germany). 4. Norway Scenario (NO): total disruption of all gas imports into Europe coming from Norway. 5. North Africa Scenario (NA): total disruption of all gas imports into Europe coming from North Africa via pipeline (all flows of natural gas in transit through Morocco, Tunisia and Libya are disrupted). The five scenarios above described have been simulated under the conditions of the available infrastructures in 2009 and 2014, and for crises of 30-day and 90-day duration. In the events occurring during 30-day long the gas consumption corresponding to January 2010 has been used for each country. For the events occurring during 90-day long, the average consumption of the three first months of 2010 has been used. In order to evaluate the impact of a gas disruption at Europe level or country level two variables are considered: the unserved amount of gas and the probability of failure of a particular country. As it was explained above, the same gas disruption scenario is run hundreds of times with GEMFLOW model. Different strategies to share gas from countries with surplus gas towards countries inneed are applied at each run. At the end of the simulation the

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amount of unserved gas is estimated as the average value obtained at each run. The probability of failure of a country represents the percentage of runs that a country fails to supply completely the demand. The average percentage of unserved gas and the probability of failure are both key variables that provide insights in the ability of a country to survive a gas disruption. There are countries that have a high probability of failure however the amount of unserved gas is insignificant, therefore the percentage of average unserved gas in Europe accounts both parameters to estimate the impact of the crisis. The overall EU percentage of unserved gas for each scenario is shown in Fig. 6. In the left hand side graph, it can be seen that there are not serious problems to satisfy the gas demand in Europe when the supply from Norway (NO) or North Africa (NA) is interrupted during 30 days, as long as the volume level of gas storages is at 70% of their volume at the beginning of the crisis and the availability of regasified gas allows to provide at least 70% of the maximum send-out capacity. The scenarios that represent harm are the gas disruption from Ukraine (UA) and from Russia (RU). It is appreciated in the figure that the unserved gas during these crises is reduced in 2014. The Russian gas disruption happening in 2009 would withdraw 3.6% of the total European supply, however the same crisis happening in 2014 would withdraw 2.2%. The Ukrainian gas disruption (UA) simulation shows that 1.2% of the European gas demand could not be satisfied in 2009 but in 2014 this value decreases to 0.5%. In the graph of the right hand side in Fig. 6 the same scenarios of gas disruption have been simulated during 90 days. All the scenarios have an impact regarding the amount of unserved gas in Europe being the RU scenario the most severe both in 2009 and 2014. The reference case scenario, REF, which simulates the normal operation, shows also a deficit of gas in 2009 and 2014. This is due to the fact that some of the key storage facilities of Europe are exhausted after 90 days of continuous withdrawal, such the UGS of Belgium, Czech Republic, France, Italy or Netherlands, even if there is not a major disruption. In Figs. 7 and 8, the average percentage of unserved gas per country is shown in a map for the Ukrainian and Russian gas disruptions happening during 30 days (Fig. 7) and 90 days (Fig. 8). Although in general terms most of the countries improve their capacity to tackle these gas disruptions, the effect of gas shortages is still severe for some Member States dependent mainly on a single supply source or only a national cross-border entry. This is the case of Bulgaria, Former Yugoslav Republic of Macedonia and Finland. It is observed that the changes in the South-Eastern corridor (i.e., Romania – Bulgaria – Greece) along with the new improvements in Hungary have provided better options for the region to cope with a relevant shortage of supply both from Ukraine and total disruption from Russia. The increased storage capacity in Poland and Germany, the increment of LNG send-out capacity in France and the Netherlands, and the new bi-directional crossborder points in many MS are important upgrades to moderate the impact of the Russian crisis in 2014 scenarios. This is evident for the 30-day scenario and also for the 90-day case. It can be noted that in the 30-day and 90-day Russian gas disruptions the average percentage of unserved gas is slightly higher in 2014 for some countries, such as Italy, Estonia or Sweden. This is related to the change in the firm capacity at interconnection points declared in 201410 (see also Fig. 3) and the new bi-directional capacity implemented between MS. The solidarity approach established by the model in order to distribute the spare gas of a country is influenced by the change in the interconnection capacities and therefore the sharing out of the spare gas experienced 10

Available at: http://www.entsog.eu/maps/transmission-capacity-map/

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Fig. 6. Percentage of average unserved gas in Europe in 2009 and 2014 for each of the gas disruption scenarios simulated during 30-day and 90-day duration of the crisis.

different strategies than in 2009. This effect can be appreciated, for example, in Italy in the Russian crisis of 90 days where the average percentage of unserved gas increases from 14.3% in 2009 to 16.7% in 2014 but nevertheless, countries highly interconnected to Italy, such as Slovenia or Austria, decrease the unserved gas. Another similar example can be seen in Sweden. Swedish unserved gas increases in 2014 since Denmark shares – in the simulations – spare gas primarily with Germany thanks to a higher interconnection capacity among both countries. In the top part of Fig. 9 the average percentage of unserved gas per country is shown for the Norwegian crisis simulated during 90 days. A gas crisis caused by the total gas disruption from Norway has only a relevant impact in Europe when the event lasts longer than 30 days. This is due to the fact that the more dependent countries on Norwegian gas are located in a further diversified and interconnected gas area. The Norwegian crisis shows a lesser impact in 2014 for those countries that were affected in 2009. However in 2014 there are three new countries affected: United Kingdom, Ireland and Sweden. This is explained as result of the decreased gas production capacity in UK and Denmark in 2014. Therefore when simulating a Norwegian crisis in 2014 with the highest consumption experienced by Europe (that of winter 2010), at the moment that UK and Denmark exhaust their gas storages they cannot continue supplying their neighbours. Consequently Ireland and Sweden cannot fully satisfy their demand in the last days of the crisis. The North African crisis simulates the disruption of gas from Algeria, including the transit trough Libya, Morocco and Tunisia. The crisis has a significant effect when it lasts 90 days. It is appreciated in bottom part of Fig. 9 that the impact of the disruption has less effect in 2014 than in 2009. In 2009 the lack of sufficient gas in Italy is propagated to Switzerland and eventually to France however in 2014, thanks to the improvement in LNG and storage capacity only Italy would be affected with an expected un-served gas probability of 7.7%. The comparison of the results obtained for the simulated crises reveals an increase in the resilience of the gas system to cope with gas disruptions. In general, 2014 scenarios show a lesser impact in terms of unserved gas than 2009 scenarios. In addition, 30-day duration scenarios have a lower impact than 90-day cases. Overall it can be stated that the incorporation of new infrastructure to the European gas grid, including the availability of reverse flow, has provided more flexibility to better support shortages of supply, especially from Eastern Europe pipeline routes.

5. Conclusions & policy implications This paper provides an assessment of the effects and magnitude of the improvements implemented between 2009 and 2014 in the European high pressure grid system from the infrastructure point of view. The developments achieved in the European natural gas system can be traced back to the adoption by the European Commission on 21 September 2007 of the third package of legislative proposals for electricity and gas markets, to the application of Regulation (EU) No 994/2010 on security of gas supply, to the increased fluidity of the market (though still regionally in many cases) and the flexibility of European TSO. Relevant investments promoted by many TSO and strategically supported by the European Commission as “Projects of Common Interest”11 have created the conditions to boost the technical performance of the European gas grid to start to solve challenges of the on-going transition of the European energy system. In particular, major steps forward have been accomplished in the direction of complete an internal energy market. Regarding major gas infrastructures, between 2009 and 2014 the EU gas system has experience the following improvements:


the EU high pressure grid has grown on average 8% concerning










pipeline infrastructure. In addition the ability to transport gas has improved by increasing notably the total installed compressor power; the number of EU LNG terminals has increased by four units in the period and the nominal annual aggregated send-out capacity increased by 41% from 134 to 189 Bcm per year. Such changes provide the opportunity for many MS to reduce their dependence from a single supplier. However, the EU LNG market has experienced a substantial reduction since 2011 due to, among other factors, the decrease in gas demand; the number of UGS facilities and the working storage capacity have increased 11% and 21% respectively, with a total of 143 sites and a capacity of 100 Bcm. In line with the European energy policy, UGS is playing more and more a strategic role in providing reliable sources during crises or exceptional conditions, as it can react quickly to sudden peaks and it can be geographically near to the consumption areas; reverse flow has been substantially implemented within the EU as the number of interconnection points increased from 24% to 40% and the overall capacity at cross-border points has improved as a

11 See https://ec.europa.eu/energy/en/topics/infrastructure/projects-commoninterest

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Fig. 7. Percentage of average unserved gas of a Russian gas disruption through Ukraine – UA – (above) and a total gas disruption from Russia – RU – (below) happening in 2009 (left) and 2014 (right) during 30 days.

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Fig. 8. Percentage of average unserved gas of a Russian gas disruption through Ukraine – UA – (above) and a total gas disruption from Russia – RU – (below) happening in 2009 (left) and 2014 (right) during 90 days.

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Fig. 9. Percentage of average unserved gas of a total gas disruption from Norway – NO – (above) and a total gas disruption from North Africa – NA – (below) happening in 2009 (left) and 2014 (right) during 90 days.

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whole by 10.6% from 2997 Mcm/d to 3315 Mcm/d. However some relevant bottlenecks still exist in the EU grid (e.g. the South-East corridor, interconnections between France and Spain or France and Germany and Belgium) and some MS are still poorly or not connected to the main EU gas system (e.g. the Baltic region and Finland, Croatia, Bulgaria and Greece). Further expansions in all these different areas will prove to be essential in short and medium term to fully develop a sufficiently diversified gas infrastructure to facilitate safe supplies to the European Union under attractive framework conditions. The second part of the report focuses on the use of a mass-balance simulation tool – GEMFLOW – to assess the effects of the infrastructural improvements on the overall behaviour of the European natural gas high pressure system under specific crisis scenarios. The simulation tool can quantify in statistical terms probability and impact of failure for each country by considering all the links and interactions of the key components of the EU gas system. In addition GEMFLOW can help to understand where possible cross-border bottlenecks are and where actions could be addressed. Several scenarios were analysed. The scenarios simulating the partial cut of supply from Russia through Ukraine and the total cut of gas from Russia during a period of 30 and 90 days show that in all cases the overall amount of unserved gas in 2014 decreased at EU level and, in general, at MS level. This reveals that the incorporation of new infrastructure, including the availability of reverse flow, has provided more flexibility to better support shortages of supply from Eastern Europe pipeline routes. However the impact of the simulated gas crises could still be severe for some Member States, which are isolated or dependent on a single supply source, such as the case of Bulgaria, Former Yugoslav Republic of Macedonia, Finland or the Baltic Region. The starting of commercial operations of the LNG terminal of Klapédia (Lithuania) in January 2015 and the up-coming new LNG facilities of Świnoujście (Poland) in 2016 will improve the situation of the NorthEastern region. On the other hand, the changes in the SouthEastern corridor (i.e., Romania – Bulgaria – Greece) along with the new improvements in Hungary have provided better options for the region to cope with a relevant shortage of supply. Other changes in the EU infrastructure, such as the increased storage capacity in Poland and Germany, and the increment of LNG sendout capacity in France and the Netherlands, are important upgrades to moderate the impact of a Russian crisis in 2014 scenarios. These upgrades of infrastructure have been proved in turn key to mitigate the impact of a long-term gas crisis happening when the supply from Norway or Algeria is disrupted.

Acknowledgements This paper has been carried out within the framework of the project EU-Gas of the Joint Research Centre of the European Commission. The authors want to thank two anonymous reviewers for comments that greatly improved the manuscript.

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