Analysis of energy security level in the Baltic States based on indicator
approach
Juozas Augutis a, b
, Ricardas Krikstolaitis a, b
, Linas Martisauskas b, *
, Sigita Urbonien_e a
,
Rolandas Urbonas b
, Aist_e Barbora Uspurien_e a
a
Vytautas Magnus University, Kaunas, Lithuania
b
Lithuanian Energy Institute, Kaunas, Lithuania
a r t i c l e i n f o
Article history:
Received 27 October 2018
Received in revised form
25 February 2020
Accepted 18 March 2020
Available online 20 March 2020
Keywords:
Energy security indicator
The Baltic States
Energy security level
a b s t r a c t
Energy security for small countries like Estonia, Latvia and Lithuania, which are called the Baltic States, is
vital for ensuring energy independence and is a driving force for the development of a strong economy.
The aim of the study presented in this paper is an analysis of the Baltic States regarding the performance
of energy security level based on indicators. The analysis covers 2008e2016, in which the Baltic States
faced essential changes in the energy sector. The methodology, based on indexes, is adopted for an integral
measure of energy security level. The system of indicators is proposed, which considers technical,
economic, geopolitical and sociopolitical aspects of energy security. The indicator system using statistical
data is applied to each Baltic State, which enables evaluation of energy security level. The application of
the developed model demonstrates which measures strengthen energy security. The results demonstrate
that the energy security level of Estonia and Latvia is higher in comparison to Lithuania. The main factors
for these differences are that Estonia and Latvia have strong own energy resources, such as oil shale and
hydropower respectively, while Lithuania is characterized by high level of electricity import.
© 2020 Elsevier Ltd. All rights reserved.
1. Introduction
A secure supply of reliable energy services at affordable prices is
essential to promote economic growth. This directly refers to the
energy security concept, which still does not have an acceptable
and agreed definition within the existing literature in the field.
Many studies concentrate on defining, conceptualizing and
measuring energy security. Ang et al. [1] surveyed 104 studies from
2001 to June 2014, reporting the findings of energy security definitions,
dimensions and indexes as well as methodological issues
during the development of these indexes. Azzuni and Breyer [2]
agree that current research literature lacks a commonly accepted,
precisely defined definition of energy security and provide an
advanced review of definitions and dimensions of energy security.
However, most of the reviewed studies agree with the definition
provided by the International Energy Agency, which states that
energy security has many aspects and should cover the uninterrupted
availability of energy sources at an affordable price [3].
Ensuring energy security is particularly challenging for small
countries, such as Estonia, Latvia and Lithuania. In recent years,
Baltic States have undergone major changes in the energy sector,
which have a great impact on strengthening energy security in the
Baltic region. Nevertheless, energy security topic in the research
field considering these States does not receive so much attention,
specifically when measuring energy security. However, energy security
for the Baltic States has been analysed in some of the studies,
which briefly are reviewed in Section 2.
The goal of the study presented in the paper is twofold. Firstly,
using best practises it proposes a composite energy security measure
by integrating various indexes into a single characteristic
called the energy security level (ESL). It allows to estimate past and
future status of energy security of the analysed system and demonstrates
which measures strengthen energy security. Secondly,
using the latest available statistical data it evaluates the energy
security level for the Baltic States in 2008e2016 and complements
similar studies with the comprehensive analysis of energy security
performance for these States. Additionally, the study is supplemented
with uncertainty and sensitivity analysis that contributes
* Corresponding author.
E-mail addresses: juozas.augutis@vdu.lt (J. Augutis), ricardas.krikstolaitis@vdu.lt
(R. Krikstolaitis), linas.martisauskas@lei.lt (L. Martisauskas), sigita.urboniene@vdu.
lt (S. Urbonien_e), rolandas.urbonas@lei.lt (R. Urbonas), aiste.uspuriene@vdu.lt
(A.B. Uspurien_e).
Contents lists available at ScienceDirect
Energy
journal homepage: www.elsevier.com/locate/energy
https://doi.org/10.1016/j.energy.2020.117427
0360-5442/© 2020 Elsevier Ltd. All rights reserved.
Energy 199 (2020) 117427
to a better understanding of energy security level of the Baltic region,
as well as provides additional information to the decisionmakers
at the European Union (EU) level.
The remaining part of the paper is structured as follows: Section
2 contains a brief literature review on energy security for the Baltic
States; Section 3 briefly presents energy country profiles; the proposed
methodological approach is described in Section 4; the results
of analysis of energy security level during 2008e2016 of the
Baltic States are discussed in Section 5; Section 6 of conclusions
summarizes main findings of the conducted study.
2. Literature review
The World Energy Council (WEC) annually prepares so-called
the World Energy Trilemma Index (WETI), which is based on
three core dimensions (energy security, energy equity and environmental
sustainability) and ranks energy systems of 125 countries
worldwide [4]. In the latest report of 2018 in terms of energy
security dimension, Latvia is ranked as 11th, Estonia as 19th and
Lithuania as 46th. The main disadvantage of this index is that it
does not provide values of the index dimensions, but demonstrates
only country ranking.
The global Energy Architecture Performance Index (EAPI) also
ranks worldwide countries, particularly on their ability to deliver
secure, affordable and sustainable energy [5]. The EAPI provides
index values on a scale of 0e1. Results of the latest report in 2017
demonstrate the energy system performance of 127 countries using
the EAPI scores [5]. According to sub-index “energy access and
security”, Latvia among the Baltic States has the highest score of
0.80 in 2017, while Lithuania and Estonia observed 0.78 and 0.75
respectively.
Global national energy security was evaluated by Wang and
Zhou [6] using Energy Security Index (ESI). Evaluated 162 countries
were categorized into 9 sub-groups in terms of energy security
performance in different regions. The Baltic States were clustered
into Eurasia and among these countries, Latvia and Lithuania were
in the Good (I) group or second best out of nine, while Estonia was
classified as Limited (II) or fifth out of nine.
Chalvatzis and Ioannidis [7] studied energy supply security in
the EU countries considering diversity and dependence metrics,
such as import dependence, ShannoneWiener index (SWI) and
HerfindahleHirschman index. It is observed that Latvia and Estonia
have reduced their import dependence due to renewable energy
growth. However, Estonia is determined as one of the countries
with the least diverse fuel mix.
Matsumoto et al. [8] evaluated energy security in the EU countries
concentrating on diversity, import dependence and supply
risk. However, the analysis ends in 2014, which means that
Lithuania and Latvia were still non-OECD countries at that time
moment. For such countries, only diversity indicator was applied,
which does not demonstrate the entire picture.
The energy security index, which covers environmental and
social aspects, was proposed by Radovanovic et al. [9] and applied
to the EU countries from 1990 to 2012. Estonia and Lithuania in
2012 were grouped into the first category, meanwhile, Latvia fall in
the fourth category. Since the index does not provide any threshold
values, the results are difficult to interpret. Also, it is surprisingly
low energy security index for Sweden and Latvia and high index for
Lithuania in 2012, which does not properly address the reality.
Thus, this index is not an informative measure in terms of energy
security.
Other energy security index, constructed using the five most
common dimensions of energy security (availability, affordability,
accessibility, acceptability and efficiency), was developed by Erahman
et al. [10] and applied for 71 countries. In 2013, observed
values of this index for Estonia, Latvia and Lithuania were 0.641,
0.610 and 0.598 (on a scale of 0e1) respectively, while the average
index value of all analysed countries was 0.593. Although the
analysis covers many countries, however, the last year of the
analysis is 2013, which does not reveal an energy security performance
in recent years.
The security of external energy supply in the EU was analysed by
Le Coq et al. [11] for oil, natural gas and coal. Risky External Energy
Supply (REES) index was considered for the assessment, which
demonstrated one of the highest risks in terms of natural gas
supply in Latvia and Lithuania in 2006. Furthermore, in terms of
crude oil, Lithuania was reported as having one of the highest
supply risks as well.
Socioeconomic Energy Risk Index was presented by Delgado
[12] for the EU-25 countries. The highest risk in 2009 was determined
in Latvia (40.9), Lithuania (40.8) and Estonia (38.1), while the
average value for the EU-25 was 28.9. Similarly, Geopolitical Energy
Supply Risk Index (GESRI) was proposed by Mu~noz et al. [13] that
aims to quantitatively estimate the geopolitical risk of energy
supply. The index was applied for 122 countries and aggregated
over the period 2000e2010. As a result, Estonia is ranked as 28th,
Lithuania is 30th and Latvia is ranked as 33rd.
Composite indicators for the security of energy supply were
proposed by Badea et al. [14] using ordered weighted averaging for
the EU countries in 2010. In this study, the Baltic States are identified
with the highest risk in terms of security of energy supply.
Number of studies, which concentrate on the energy security
purely for the Baltic States, in particular using indicator approach, is
quite limited at present to the best of authors’ knowledge. Security
of electricity supply of the Baltic States in future perspective was
analysed by Bompard et al. [15], pointing out that the network
security level in 2030 will be lower and even inferior to the security
level compared with 2014 and 2020.
Study on the security of energy supply for the Baltic States
proposed an index, which quantitatively assesses political vulnerability
[16]. The analysis has revealed that the overall political
vulnerability on the security of energy supply is the highest in
Lithuania, considerably lower in Latvia, and the lowest in Estonia.
Various energy security indicators were analysed for the Baltic
States for the period of 2003e2012 [17]. However, an aggregate
measure has not been proposed and different indicators do not
demonstrate the integral energy security level. Therefore, countries
cannot be compared in terms of energy security.
One of the most recent studies of energy security trends in the
Abbreviations
EAPI Energy Architecture Performance Index
ESI Energy Security Index
ESL Energy Security Level
EU European Union
GESRI Geopolitical Energy Supply Risk Index
GHG Greenhouse Gas
NPP Nuclear Power Plant
LNG Liquefied Natural Gas
NEIS National Energy Independence Strategy
REES Risky External Energy Supply
RES Renewable Energy Sources
SWI ShannoneWiener index
WEC World Energy Council
WEF World Economic Forum
WETI World Energy Trilemma Index
J. Augutis et al. / Energy 199 (2020) 1174272
Baltic States for the period of 2008e2012 uses the multi-criteria
decision-making technique for aggregate measures of energy security
[18]. The study demonstrated that in terms of energy security
Latvia performs the best, while Estonia and Lithuania are more
similar lower-performing.
The reviewed studies revealed that energy security for the Baltic
States is evaluated very differently, which results in a quite different
performance of energy security within these States (Table 1).
The main reason for this discrepancy is non-existence of
acceptable and agreed criteria or measure that would impartially
and integrally allow to assess the energy security level. It still lacks
a comprehensive analysis of energy security for the Baltic States
that would allow to quantitatively measure different security dimensions
by an integral metric. Also, uncertainties are neglected in
most of the cases when analysing energy security indicators.
The study presented in this paper fills the gap of such type of
analyses. Since the Baltic States is a specific case in terms of energy
security within the EU, the analysed issue is particularly important
when taking into account energy planning purposes. The importance
of the Baltic States’ role within the EU’s energy system is
highlighted in Section 3. Yet, it is extremely important to provide
both simple and comprehensive measures for energy security to
make the decision-making process most effectively. The study
presented in this paper covers these aspects by both methodological
and practical contributions.
The methodological contribution is represented by the indicator
system, which forms a basis for an integral energy security measure
that evaluates energy security quantitatively considering not only
technical and economic but also geopolitical and sociopolitical dimensions.
The practical contribution of this study is demonstrated
by the comprehensive analysis of the energy security performance
of the Baltic States, which enables a comparison of energy security
dynamics from 2008 to 2016 within different dimensions and types
of energy. The outcomes of the method application are beneficial
for the decision-making process at the national, regional and EU
levels when supporting energy planning and energy policy.
3. Energy profiles of the analysed countries
To better justify the application of indicators for energy security
assessment of the Baltic States, a brief overview of the energy
profile of each analysed country is provided. Though the Baltic
States politically and economically are the members of the EU,
however, their electricity and natural gas systems are still mostly
connected with the systems of the former Soviet Union. This situation
was determined both by historical and political circumstances
and by limited internal energy resources.
For a long time, the Baltic States were called as an “energy island”
in Europe, as it is underlined in the European Energy Security
Strategy [19]. The Baltic States in the EU’s energy system were
without electricity networks, gas pipelines and interconnections
with Western Europe [20]. From the point of view of European
integration, the Baltic States in some extent still remain an isolated
“energy island” since electricity systems were developed as an integral
part of the Interconnected Power System/Unified Power
System (IPS/UPS) and work synchronously with power systems of
Belarus, Russia and other Eastern countries. In order to be integrated
with the European electricity system, the project of synchronisation
of the Baltic States’ electricity grid with the European
Continental Network (ECN) is foreseen to be implemented by 2025.
Table 1
Summary of energy security estimates for the Baltic States.
Study [ref.] Index Analysis
period
Index estimate (in the latest year analysed) Scale
Estonia Latvia Lithuania
WEC [4] WETI 2014e2018 19th 11th 46th Rank (out of 125) (higher values correspond to
lower rank)
WEF [5] EAPI (Energy Access and
Security)
2013e2017 0.75 0.8 0.78 [0; 1] (higher values correspond to higher
energy security)
Wang and Zhou [6] ESI Not specified 5th 2nd 2nd 9 sub-groups (higher values correspond to
lower rank)
Chalvatzis and
Ioannidis [7]
SWIa
1990e2012 0.81 1.21 1.49 !0 (higher values correspond to higher
diversity)
Matsumoto et al. [8] SWIa
1990, 2002,
2013
0.81 1.38 1.26 !0 (higher values correspond to higher
diversity)
Radovanovic et al. [9] ESI 1990e2012 þ92.01 (1st
group)
À65.31 (4th
group)
þ62.12 (1st
group)
Four groups:
1) > þ55
2) [þ15; þ55]
3) [e25; þ15]
4) < À25
(higher values correspond to higher energy
security)
Erahman et al. [10] ESI 2008e2013 0.641 0.610 0.598 [0; 1] (higher values correspond to higher
energy security)
Le Coq et al. [11] REES 2006 1.9 (Oil) 2.1 (Oil) 10.2(Oil) !0 (higher values correspond to higher risk)
10.3 (Gas) 21.0 (Gas) 20.1 (Gas)
0.3 (Coal) 0.6 (Coal) 1.0 (Coal)
Delgado [12] Socioeconomic Energy Risk
Index
2009 38.1 40.9 40.8 [0; 100] (higher values correspond to higher
risk)
Mu~noz et al. [13] GESRIb
2000e2010 37.63 39.02 38.36 [0; 100] (higher values correspond to higher
risk)
Badea et al. [14] Composite indicator 2010 15th 17th 24th Rank (out of 27) (higher values correspond to
lower rank)
Cesnakas et al. [16] Political vulnerability 2004e2011 31.45 45.25 56.12 [0; 100] (higher values correspond to higher
vulnerability)
Zeng et al. [18] The integrated energy security
indicatora
2008e2012 0.52 0.86 0.47 [0; 1] (higher values correspond to higher
energy security)
a
Values are estimated approximately since the study results are provided in the graphical form only.
b
Values are aggregated over the 2000e2010.
J. Augutis et al. / Energy 199 (2020) 117427 3
Therefore, energy security is still an issue of the highest relevance
for the Baltic States.
However, much effort has already been made to improve the
situation and move towards energy independence and increased
energy security. As an example, formerly an “energy island”, the
Baltic States is now connected with the EU through recently constructed
electricity lines with Poland, Sweden and Finland, it contributes
to the establishing a unified European energy market.
Apart from being in BRELL (Belarus, Russia, Estonia, Latvia and
Lithuania) ring and operating in parallel with the IPS/UPS, energy
systems of the Baltic States have more features in common. All
three countries are still strongly dependent on natural gas import,
lack of own/local resources, face a similar environment of threats to
energy security [21]. Nevertheless, each of the Baltic States has a
focus on a different energy resource, especially when analysing
energy production and consumption (Fig. 1).
However, all three States are quite consistent with their commitments
regarding the share of renewable energy sources (RES) in
final energy consumption and perform better than the EU28
average (Fig. 2).
These and similar aspects are also emphasized further in the
country energy profiles and Section 5 of the results.
3.1. A general overview of the Lithuanian energy system
The considerable change in the Lithuanian energy system
occurred at the end of 2009 after closing the Ignalina Nuclear Power
Plant (NPP). It radically changed the energy resource structure
and suddenly country from exporting electricity overnight became
country importing electricity. This event increased energy dependence
on Russia not only in terms of electricity import, but also
dependence on natural gas import as the production of electricity
from gas-fired power plants was also increased.
In 2016, total production of electricity in Lithuania amounted to
3.973 TWh [22]. As indicated in Fig. 1, the largest part of the production
came from wind (28%), hydro (25%) and natural gas (21%)
[23]. However, total demand for electricity in Lithuania in 2016 was
12.247 TWh [22]. It means that 68% of demanded electricity was
imported, particularly from Latvia (35.8%), Russia (29.9%), Sweden
(27.3%), Poland (4.8%), Belarus (1.5%) and Estonia (0.6%) [24].
At the end of 2015, two new power connection lines, accordingly
“LitPol Link” with Poland of 500 MW and “NordBalt” with Sweden
of 700 MW were commissioned, thus, their real benefit in terms of
decreased electricity price and diversification of electricity supply
is felt from 2016. It was major step in terms of strengthening the
country’s energy independence and security.
Till 2015, Lithuania relied on a single source of natural gas
supply from Russia. However, diversification of gas supply was
reached by introducing a liquefied natural gas (LNG) terminal in
Klaip_eda at the end of 2014. It has enabled the formation of a
natural gas market in Lithuania and a decrease in natural gas prices
in the country, and most importantly, strengthened national energy
security [25].
The main strategic directions of energy policy development
pointed out in new National Energy Independence Strategy (NEIS)
of Lithuania are energy security, competitiveness, green energy
development and innovations [26]. According to the NEIS, the main
vision of the Lithuanian energy sector is complete independence
from fossil fuels by 2050. It seems this vision can be fulfilled since
the share of RES in gross final energy consumption increased from
17.2% to 25.6% between 2004 and 2016. As illustrated by Fig. 2, the
country in 2014 has already reached the national RES target of 23%
for 2020 defined by the renewable energy directive [27].
3.2. A general overview of the Latvian energy system
RES have a dominant share in total production of electricity in
TWh
Fig. 1. Electricity production and consumption balance in the Baltic States in 2016.
Fig. 2. Share of RES in gross final energy consumption in 2004 and 2016.
J. Augutis et al. / Energy 199 (2020) 1174274
Latvia (54% in 2016), mainly being generated by hydro (40%),
biomass (6%), biogas (6%) and wind (2%) [23]. As indicated in Fig. 1,
the other part of 6.293 TWh produced electricity in 2016 came from
fossil fuels. As total demand for electricity in 2016 was 7.323 TWh,
the rest of the demanded electricity (14%) was imported, mostly
from Estonia (61.8%) and Russia (22.9%) [23]. Heat production also
mostly relies on natural gas. Since Latvia does not have its own
resources, all natural gas consumed is imported from a single
source e Russia.
Unlike the other Baltic States, Latvia operates the Incukalns
Underground Gas Storage Facility, which ensures the stability of
regional natural gas supply [29]. Natural gas is injected into the
storage during the summer, when consumption is low, and supplies
gas during the heating season.
Due to strong hydropower production, Latvia is one of the
leading countries according to the share of energy from RES in the
EU and is close to achieve its 2020 RES target. In 2016, the share of
RES in gross final energy consumption amounted to 37.16%, which
is more than twice higher than the EU28 average (Fig. 2). Furthermore,
Latvia’s RES target for 2020 is 40%, which is also twice as high
as the EU average of 20%, defined by Ref. [27] and Latvia is very
close in achieving it.
3.3. A general overview of the Estonian energy system
Estonia is the only country in the world that has oil shale as the
primary energy source in the country and as a dominating fuel in
the energy mix. On the one hand, such high consumption of oil
shale as a local fuel ensures high level of energy security. On the
other hand, it is highly carbon-intensive fuel, thus oil shale based
energy production processes emit a large amount of greenhouse
gas (GHG), which has negative impact to the environment.
For this reason, Estonia in 2015 within the EU countries with
regard to GHG emissions intensity of the economy was in the first
place (index of GHG emissions/GDP (EU28 ¼ 100) was 217) and
with regard to GHG emissions per capita was in the second place
(13.7 t CO2 eq. per capita) [30]. This makes Estonia’s economy more
than twice as carbon dioxide (CO2) intensive as the EU average. In
order to significantly reduce CO2 emission and to lessen the
negative environmental impact, the Estonian Government is
phasing out old power plants and developing new technologies
[31].
Estonia’s electricity production is slightly higher than consumption,
thus it exports electricity. In 2016, total production of
electricity in Estonia amounted to 10.423 TWh, whereas total demand
for electricity was 8.387 TWh [23]. As detailed in Fig. 1, most
of the electricity production came from oil shale (86%), less
noticeable was biomass (7%), wind (6%) and, renewable waste (1%)
power plants. 2.036 TWh of electricity was exported to Latvia (84%)
and Finland (16%) [32].
In 2014, new power connection line “EstLink 2” has added
650 MW of transmission capacity between Finland and Estonia,
which allowed to increase for total of 1000 MW capacity since the
first high-voltage direct current interconnection “EstLink 1” with
nominal transmission power of 350 MW was already commissioned
in 2006 [33].
Though Estonia has reliable electricity supply and local oil shale
resources, but all the country’s natural gas and oil products
consumed are imported from neighbouring countries, specifically
from Russia. Nevertheless, Estonia is actively promoting the
development of RES and has already in 2011 reached the national
RES target of 25% for 2020 [28]. Thus, it made Estonia the first
country in the EU to achieve this target [34]. From 2004 to 2016 in
Estonia the share of RES in gross final energy consumption
increased from 18.4% to 28.8% (Fig. 2).
4. Methodology
The main goal of the presented methodology is to propose a
measure for an integral energy security level. The background of
the methodology are previous authors’ studies [35,36], which were
based on the work of Bykova [37]. In these studies, the concept of
energy security indicators was presented. During the implementation
of projects of the National Research Programme “Future
Energy” in Lithuania from 2010 to 2014, the methodology of
assessment of ESL was developed [38,39]. Besides, it was applied in
2015e2016 when conducting the energy security study, which was
a part of preparing a new National Energy Independence Strategy of
Lithuania [26].
The proposed methodology in the paper is an upgrade of previous
studies discussed above. The special attention was paid to
reconstruction and significant improvement of the system of indicators,
which enable to cover numerous aspects of energy security
peculiarities. Also, the system was designed to be as general as
possible and suitable for any application. Using the methodology,
estimation of ESL in general might be applied for both past and
future energy systems.
4.1. System of indicators
According to the methodology, ESL is assessed regarding all
factors that have an impact on energy security. A system of energy
security indicators is developed and converted to an integral energy
security measure. The energy security indicator is a special
index, which provides numerical values. Selected indicators are
divided into three blocks e technical, economic and sociopolitical.
Blocks are divided into the specific groups, which should be
formed according to the type of energy source or fuel used in the
energy system, e.g. electricity, heat, natural gas, oil, coal, nuclear or
other.
The normalized value of an indicator is denoted as Iijk, where i ¼
1; …; n is the number of block, j ¼ 1; …; mi e the number of group in
the ith block and k ¼ 1; …; lj e the number of the indicator in the jth
group. General scheme of ESL is presented in Fig. 3.
Indicators I are formed from various indexes, which of the
proposed methodology for each of the blocks are described in detail
below.
4.1.1. Technical block
The technical block consists of 8 key indexes that reflect technical
aspects of energy security. Most of these indexes are formed as
ratios or shares of particular parameters that relate to the technical
block dimension. Mathematical approach of technical indexes is
presented further.
1) Ratio of total installed capacity to maximum demand for
capacity
T1 ¼ TCinj

MDj; (1)
where TCinj e total installed capacity of energy source j, MDj e
maximum demand for capacity of energy source j.
2) Ratio of total capacity of supply to final consumption
T2 ¼ TCsuj

FConj; (2)
where TCsuj e total capacity of supply of energy source j, FConj e
final consumption of energy source j.
3) Ratio of the installed capacity of the largest unit to total
installed capacity
J. Augutis et al. / Energy 199 (2020) 117427 5
T3 ¼ LCinj

TCinj; (3)
where LCinj e the installed capacity of the largest unit of energy
source j.
4) Ratio of the capacity of the largest supplier to final
consumption
T4 ¼ LCsuj

FConj; (4)
where LCsuj e the capacity of the largest supplier of energy source j.
5) Share of the largest production of one technology in total
production
T5 ¼ LProj

TProj; (5)
where LProj e the largest production of one technology of energy
source j, TProj e total production of energy source j.
6) Ratio of the amount of accumulated reserves to final
consumption
T6 ¼ ARj

FConj; (6)
where ARj e the amount of accumulated reserves of energy source j.
7) Share of RES in gross final energy consumption
T7 ¼ REConj

FConj; (7)
where REConj e the amount of RES consumed for energy source j.
8) Share of production which can be replaced by alternative fuel
T8 ¼ AFProj

TProj; (8)
where AFProj e the amount of production of energy source j using
alternative fuel.
4.1.2. Economic block
The economic block consists of 9 key indexes that reflect the
economic aspects of energy security. As in the case of the technical
block, most of the economic indexes are formed as ratios or shares.
Mathematical approach of economic indexes is presented further.
1) Ratio of the amount purchased in the market to final
consumption
E1 ¼ Mj

FConj; (9)
where Mj e the amount of energy source j purchased in the market.
2) Ratio of the purchase price to the average price of the EU
countries
E2 ¼ Prij

EUPrij; (10)
where Prij e the purchase price of energy source j, EUPrij e the
average price of energy source j of the EU countries.
3) Ratio of the purchase price to the average price in the available
markets
E3 ¼ Prij

MPrij; (11)
where MPrij e the average price of energy source j in the available
markets.
4) Ratio of the production price to the average production price
of the EU countries
E4 ¼ ProPrij

EUProPrij; (12)
where ProPrij e the production price of energy source j, EUProPrij e
the average production price of energy source j of the EU countries.
5) Share of consumers who may choose a supplier of energy
source/fuel j freely (E5). This index shows which part of the consumers
can freely choose the supplier of the corresponding energy
source or fuel.
6) Ratio of the amount of energy source which can be produced
using fuel imported only from a single supplier to total amount of
production
E6 ¼ FSsuj

TProj; (13)
where FSsuj e the amount of energy source j which can be produced
using fuel imported only from a single supplier.
7) Share of the import/supply from a single supplier
E7 ¼ ImpSsuj
.
TImpj; (14)
where ImpSsuj e the amount of the imported energy source j from a
single supplier, TImpj e total amount of the imported energy source
j.
8) Ratio of the amount of import to final consumption
E8 ¼ TImpj
.
FConj: (15)
9) Ratio of the amount of the local fuel, used for the production,
to final consumption
E9 ¼ LFProj

FConj; (16)
where LFProj e the amount of the local fuel, used for the production
Fig. 3. Blocks, groups and indicators of energy security level.
J. Augutis et al. / Energy 199 (2020) 1174276
of energy source j.
4.1.3. Sociopolitical block
The sociopolitical block is described by 7 key indexes that
mostly cover geopolitical and sociopolitical dimensions of energy
security. Mathematical approach of sociopolitical indexes is presented
further.
1) Energy dependence
SP1 ¼
X
j
TImpj
,
X
j
FConj: (17)
2) The weighted mean of political risk factors of the countries
SP2 ¼
X
c
À
wc;k  Rc
Á
; (18)
where wc,k e weight according to the criteria k of country c, Rc e
political risk factor of country c.
Criteria k is as follows:
k ¼ 1 e according to the size of import of energy sources from
countries c; k ¼ 2 e according to the size of transit of energy sources
through countries c; k ¼ 3 e according to foreign countries c that
have invested into national energy system; k ¼ 4 e according to the
size of connections of countries c that electricity transmission
network is connected with.
3) The political risk factor of the country
SP3 ¼ Rc: (19)
4) Share of energy expenses per household in total household
expenses
SP4 ¼ EHE=THE; (20)
where EHE e energy expenses per household, THE e total household
expenses.
5) Degree of undertaking the commitment with regard to share
of RES in final energy consumption
SP5 ¼ T7=RET; (21)
where T7 e the share of RES in gross final energy consumption
evaluated by index T7 using formula (7), RET e the national RES
target for 2020 defined by the EU renewable energy directive [27].
6) Degree of following the commitment with regard to the
reduction of greenhouse gas emission (SP6). This indicator shows
country’s trend in total man-made emissions of the “Kyoto basket”
of greenhouse gases. It presents annual total emissions in relation
to 1990 emissions [40].
7) Degree of undertaking the commitment with regard to the EU
energy efficiency target
SP7 ¼
X
j
FConj
,
EET; (22)
where EET e the national energy efficiency target for 2020 defined
by the EU energy efficiency directive [41].
4.2. Energy security level
Usually, factual values of indicators have various dimensions
and scales with different maximal values. Thus, primarily all values
of indicators should be normalized, i.e. turned into a 100% scale by
using a compression ratio.
In order to evaluate ESL, the state of each indicator should be
identified according to its direction. There are denoted 3 states of
indicator (as well as for general ESL): normal, pre-critical and
critical. These states are separated from each other by threshold
values of the indicator: Ipc
ijk
e pre-critical threshold value; Ic
ijk
e
critical threshold value. The threshold values of each indicator are
determined using expert evaluation method. According to their
nature indicators could be of the 2 directions: oriented to maximal
value (when Ipc
ijk
> Ic
ijk
) and oriented to minimal value (when
I
pc
ijk
< Ic
ijk
). In the first case, the higher value of the indicator corresponds
to the higher level of security, whereas in the second case it
is vice versa. The initial idea of using such a scale of threshold
values was taken from Bykova [37]. However, the authors estimated
the indicators in points from 0 till 100 using their factual values, an
evaluation scale (see Fig. 4 c)) and considering direction and
threshold values (Ipc
ijk
and Ic
ijk
) of each indicator (see Fig. 4 a) and b)).
According to obtained points, the state of the indicator is determined
as critical (0e33 points), pre-critical (34e66 points) and
normal (67e100 points).
The integral characteristic of ESL is evaluated using (23) formula
and taking into account weights of indicators, groups and blocks:
ESL ¼
Xn
i¼1
0
@si
Xmi
j¼1
0
@sij
Xlj
k¼1
sijkIijk
1
A
1
A; (23)
where sijk ¼ 1=lj e weight of the kth indicator in the group, sij e the
weight of the jth group in the block, si ¼ 1=n e weight of ith block,
i ¼ 1;…;n; j ¼ 1;…;mi; k ¼ 1;…;lj. The weight sij for the technical
and economic blocks is determined as the share of each fuel,
electricity and heat final consumption comparing to total final
consumption. For sociopolitical block the weight sij ¼ 1=mi, i ¼ 1;
…;n; j ¼ 1;…;mi.
In summary, the model for ESL estimation deals with two types
of parameters:
1) Indicators (I). If ESL is evaluated for the past, indicator values are
collected from the available statistical data using reliable data
sources. Thus, it is hardly to expect any uncertainty or one can
expect very low uncertainty in the initial data. However, if ESL is
evaluated for the future, indicator values use predictions or
forecasts, which might lead to the uncertainties. In order to
avoid misleading results, uncertainty analysis of indicator
parameter shall be performed in this case.
2) Weights (s). The model considers three types of weights: block,
group and indicator. In the analysis, it is assumed that all three
dimensions (technical, economic, socio-political) have the same
impact on energy security in general. Thus, the weight for each
of the block is considered as equal (1/3). Group weights are
determined directly from the statistical data, therefore the uncertainties
are avoided. However, selection of indicator weights
might be subjective since equal weights are considered. In order
to analyse what impact on the ESL results the selection of these
weights might have, sensitivity and uncertainty analysis should
be conducted.
5. Results and discussion
Methodology, presented in Section 4, was applied for construction
of an indicator system that consists of 67 indicators (listed
in the supplementary material). The indicator system was adopted
separately for each analysed country. Based on the proposed
methodology, the assessment of ESL for the Baltic States was carried
out for 2008e2016. Values for indicators were calculated for
each year as well as the ESL, which is the main result of the presented
study (Subsection 5.2). The key data sources used in the
J. Augutis et al. / Energy 199 (2020) 117427 7
study are discussed further in Subsection 5.1.
5.1. Data
In order to assess ESL, statistical data for the indicator values
during 2008e2016 was collected. The technical data such as
installed capacities, maximum demand, energy consumption,
production, supply, reserves, share of RES in gross final consumption,
alternative fuels and other was collected from electricity
transmission system operators [22,23], EUROSTAT database [40],
annual reports “Energy in Lithuania” [44], national and international
district heating associations [45,46], International Atomic
Energy Agency [50], national statistical departments databases
[32,42,43]. The economic data such as purchased, market and
production prices of energy sources and fuels, import dependency
and other was collected from Lithuanian, Latvian and Estonian
competition authorities [24,48,49], national statistical departments
databases [32,42,43], annual reports “Energy in Lithuania” [44].
Data for energy dependence indicator was derived from EUROSTAT
database [40], the political risk factor of countries is reported by
International Country Risk Guide [47], household expenses for
energy was collected from national statistical departments databases
[32,42,43]. National targets for RES, energy efficiency and
reduction of greenhouse gas emissions were defined by EUROSTAT
database [40] and EU directives [27,41]. In addition, data sources
used for each indicator are provided in the supplementary material.
5.2. Results
The obtained results demonstrate that ESL in Latvia and Estonia
are higher than in Lithuania during the entire analysis period
(Fig. 5). The ESL of Estonia falls under the normal state, in Latvia, it
is close to the normal state, while in Lithuania it is worse and only
in 2016 the ESL of Lithuania equates to the normal state.
The main negative factor for the decrease of ESL in 2010 in
Lithuania was the closure of Ignalina NPP, which highly impacted
the electricity sector. As a result, mostly the energy dependency
indicator was worsened since Lithuania from electricity exporting
country suddenly became electricity importing country. The
greatest negative influence on energy security is caused by countries’
high dependency on import from one country and disproportionally
high expenses of inhabitants for energy services in
comparison to average income. In Lithuania, the sharp drop of the
ESL was also offset by many positive factors, such as the emergence
of the electricity market, change of the largest electricity generation
unit, which resulted in more diversified electricity production. In
the case of Latvia and Estonia, the main factors that negatively
influenced energy security occurred in the geopolitical indicators.
In 2010, a decrease in the risk ratings of the analysed countries was
observed, which led to a general drop in ESL.
The highest impact on the increase of the energy security level
in Lithuania from 2012 to 2016 had reduction of the dominating
generator capacity, decline in gas consumption, decreased gas
prices for consumers due to new Klaip_eda LNG terminal, greater
diversification of suppliers due to new electricity connections with
Sweden and Poland. Other positive factors for better energy security
performance were increased share of biofuels in the heating
sector as well as a decrease in the heat prices, improved rankings of
countries from which energy sources are imported.
The moderate increase of ESL in Latvia during the same period
was influenced by falling gas prices, greater diversification of production
and fuel mix in the heat sector, improving risk ratings of
both country under analysis and its neighbouring countries, which
are suppliers of energy sources.
In the case of Estonia, from 2012 to 2016 major impact on
increased energy security had factors related to the possibility for
consumers to freely choose suppliers of electricity and gas, a
decrease of gas prices and the fulfilment of commitments in the EU.
The overall dynamics of ESL could also be explained analysing
the variation of group weights. Fig. 6 demonstrates the dynamics of
group weights in technical and economic blocks. As for Latvia and
Estonia group weights didn’t change significantly during the analysed
period, weights for Lithuania varies considerably.
With the closure of Ignalina NPP in 2009, the nuclear group was
removed from the ESL assessment. The biggest part of nuclear
weight passed to gas. As a result, the weight of the gas group in
2010 increased from 25.2% to 34.3%. As the gas supply at that time
was provided from one country, this fact is one of the main reasons
of the significant decrease of ESL in Lithuania. For example, the
weight of the gas group for Latvia in 2010 increased less than 2%
points e from 16.3% (2009) to 18.1% (2010) as well for Estonia
remained the same e approximately 6.6%. Also, these differences in
weights reflected to differences of energy security level for all
analysed countries. However, from 2010 to 2016 wt of gas groups
decrease drastically e from 34.3% (2010) to 21.6% (2016). The main
reason is that majority of district heating utilities drastically
changed fuel from gas to biofuel. Another reason is that Lithuania
became electricity importer country instead electricity exporter
Fig. 4. Scales of indicator state assessment.
J. Augutis et al. / Energy 199 (2020) 1174278
country.
The results demonstrate that the performance of the ESL of
Estonia and Latvia on average is higher in comparison to Lithuania
during 2008e2016 due to various factors, discussed in this Section.
To verify whether the obtained results do not contradict with
the results of other studies, summarized in Table 1, a comparison of
relative country ranking according to energy security estimates was
conducted. The Baltic States in each reviewed study were ranked
according to the performance of index estimate. The mean rank for
each country was calculated and compared to the country ranking
in the presented study (see Table 2).
The ESL results of the presented study fit very well with the
results of energy security estimates of other studies (see Table 2).
Estonia in majority reviewed studies (11 out of 15) has the highest
rank, while Latvia and Lithuania are indicated as rank 1 only in 4
studies and 1 study respectively. When comparing the mean
ranking, it is observed that Estonia has the highest evaluation,
Latvia is ranked as second and Lithuania e as third according to
Fig. 5. The dynamics of energy security level in the Baltic States.
Fig. 6. The variation of weights composition in the technical and economic blocks: a) Lithuania, b) Latvia, c) Estonia.
Table 2
Comparison of relative Baltic States ranking with other studies according to energy
security estimates.
Country Estonia Latvia Lithuania
Number of rank 1 (out of 3) 11 4 1
Number of rank 2 (out of 3) 3 6 6
Number of rank 3 (out of 3) 1 5 8
Mean rank 1.33 2.07 2.47
Ranks in the presented study 1 2 3
J. Augutis et al. / Energy 199 (2020) 117427 9
energy security estimates.
In order to investigate the influence of indicator weights on ESL,
the uncertainty and sensitivity analysis of these weights was carried
out for the analysed countries. Indicator weights in the group
were randomly simulated using Monte Carlo method. For simulations,
Uniform probabilistic distribution with parameters [0, 1] was
used. 100 runs were performed and the dynamics of ESL for these
simulations are presented in Fig. 7. The analysis was performed by
employing Software for Uncertainty and Sensitivity Analyses
(SUSA) [51,52].
Main descriptive statistics of ESL simulations were calculated
and the average ESL of simulated weights approach was compared
with the ESL, obtained using equal weights approach. As seen in
Fig. 7, the uncertainty analysis for analysed countries resulted in a
very similar outcome, therefore results in more detail are presented
only for Lithuania (Table 3) since the influence of indicators is
dispersed the most.
It was observed that differences between ESL of indicators equal
weights approach and average ESL of simulated weights approach
are not more than 0.34% in the case of Lithuania (Table 3). For Latvia
and Estonia, this difference resulted even in lower estimates, 0.15%
and 0.18% accordingly.
Results in Table 3 demonstrate that the difference between
minimum and maximum values of simulated ESL varies from 9.25
(in 2008) to 10.69 (in 2015). The dispersion of ESL simulations was
evaluated by the relative standard deviation. The maximum relative
standard deviation for Lithuania is 3.99% in 2010, while Latvia
and Estonia resulted in 3.02% and 3.69% accordingly, which demonstrates
low degree of uncertainty in the ESL results.
A sensitivity analysis was performed to evaluate the influence of
individual indicator weight on the energy security level and identify
the key input indicators on the results. The sensitivity of indicator
weights was measured by standardized regression coefficient
(Pearson’s ordinary). Higher absolute values of this coefficient
indicate higher impact of the indicator to the ESL. All indicators
were ranked and five indicators with the highest rank were
selected for each analysed country. Dynamics of standardized
regression coefficients for these five indicators for each analysed
country are presented in Fig. 8.
The results of sensitivity analysis demonstrate that indicators1
from the socio-political block are among mostly contributing to
the uncertainty of ESL. Indicators from gas group more contribute
to uncertainty in the ESL in Latvia and Lithuania, while ESL of
Estonia is more impacted by heat group indicators. In summary, the
results of sensitivity and uncertainty analysis demonstrate that
selection of indicator weights has low uncertainty in the ESL
results.
5.3. The area of methodology application
The methodology presented in this study might be applied not
only for the Baltic States, but for any country or energy system. For
this purpose, groups and indicators (Fig. 3) should be selected according
to the configuration or structure of the country under
consideration. Various types of energy or fuels might be analysed
(supplemented or neglected of the existing ones). For instance, if
the country does not have a district heating system or nuclear
energy, it can be removed from the list of indicator group or, vice
versa, if the country has a specific type of fuel used for energy
production or consumption, it can be included in the list of indicator
group. Thus, the main modification needed for applying the
methodology for energy security level quantification for other
countries is only for indicator groups. The algorithm of calculations,
described in subsection 4.2, does not need to be modified.
The obtained results in the presented study are beneficial for the
Fig. 7. The dynamics of ESL in 100 simulations.
1
List of all indicators is provided in the supplementary material.
J. Augutis et al. / Energy 199 (2020) 11742710
decision-making process at the national and European levels,
showing the direction for the energy infrastructure, technologies,
policy and other energy related improvements. It was already a case
for the NEIS of Lithuania. Usually, strategic energy infrastructure
projects have to be analysed not only from the technical and/or
economic point of view, but also from the energy security
perspective. For instance, a successful example of LNG terminal in
Lithuania triggered the development of this technology in the
entire EU. The presented study demonstrated that LNG terminal
was one of the key factors to improve the energy security situation
in the region.
6. Conclusions
In this paper, an analysis of three Baltic States (Estonia, Latvia
and Lithuania) with regard to the level of energy security is presented.
The methodology applied for this analysis is based on energy
security indicator approach. Various indexes are integrated
into composite energy security measure called the energy security
level which allows to estimate the status of energy security of
analysed country or energy system. ESL also demonstrates which
measures increase or decrease energy security and can be used as a
tool for decision making in energy policy and energy planning.
Energy security level in 2008e2016 for the Baltic States was
evaluated using the proposed methodology. The obtained results
indicate that Estonia has the best performance in terms of energy
security in comparison with Latvia and Lithuania during the analysed
period. All three Baltic States the highest energy security level
observed in 2016e78.5% for Estonia, 68.9% for Latvia and 66.4% for
Lithuania out of 100%. Estonia the lowest energy security level
recorded in 2008e65.4%, while Latvia and Lithuania in 2010e63.5%
and 54.2% respectively.
Estonia resulted as the best-performing country regarding energy
security mainly due to domestically extracted oil shale as local
fuel, high share of RES, low energy dependency, good fulfilment of
EU commitments and low dependency on natural gas. The main
difficulties in Estonia to have even better energy security performance
were a large amount of GHG emissions, low share of
Table 3
Results of uncertainty analysis for indicator weights for Lithuania.
Year 2008 2009 2010 2011 2012 2013 2014 2015 2016
ESL (equal weights) 56.46 58.61 54.26 54.51 54.22 57.8 60.01 64.88 66.41
Average ESL (simulated weights) 56.47 58.78 54.28 54.52 54.28 57.92 60.15 65.1 66.54
Mean difference, % 0.02 0.29 0.04 0.02 0.11 0.21 0.23 0.34 0.20
Minimum ESL (simulated weights) 51.75 53.36 48.74 49.28 49.55 53.15 55.7 60.72 62.46
Maximum ESL (simulated weights) 61.00 63.51 59.04 58.74 59.26 63.66 66.10 71.41 72.23
Difference between min and max ESL 9.25 10.15 10.30 9.46 9.71 10.51 10.40 10.69 9.77
Relative standard deviation, % 3.08 3.70 3.99 3.81 3.83 3.96 3.54 3.31 2.91
Fig. 8. Results of sensitivity analysis for highest rank indicators for each analysed country.
J. Augutis et al. / Energy 199 (2020) 117427 11
purchased electricity in a free market.
The moderate energy security level of Latvia was maintained
due to high share of RES (mainly hydropower), improving country’s
risk rating. The main obstacles to increasing energy security for
Latvia were the delay in the implementation of the third energy
package, particularly, in the gas sector, low share of purchased
electricity in a free market, the dependence of supply of energy
sources from a single supplier.
Lithuania resulted as the country with a rapidly improving energy
security level during 2012e2016. This is related to new electricity
connections with Sweden and Poland and LNG terminal,
which allowed to eliminate dependency on a single electricity and
gas supplier. Other contributing factors were a decrease in gas
consumption and, at the same time, an increase of the share of local
biofuels in electricity and heat production. The main difficulties in
Lithuania to have higher energy security were still high energy
dependency from other countries, lack of own energy resources
and high share of electricity import.
Declaration of competing interest
The authors declare that they have no known competing
financial interests or personal relationships that could have
appeared to influence the work reported in this paper.
CRediT authorship contribution statement
Juozas Augutis: Conceptualization, Methodology, Writing - review
& editing, Supervision. Ricardas Krikstolaitis: Conceptualization,
Methodology, Software, Formal analysis, Data curation,
Writing - original draft, Writing - review & editing, Visualization.
Linas Martisauskas: Methodology, Software, Formal analysis, Data
curation, Writing - original draft, Writing - review & editing,
Visualization, Project administration. Sigita Urbonien_e: Conceptualization,
Methodology, Software, Formal analysis, Data curation,
Writing - original draft, Writing - review & editing, Visualization.
Rolandas Urbonas: Methodology, Formal analysis, Writing - review
& editing. Aist_e Barbora Uspurien_e: Writing - review &
editing.
Appendix A. Supplementary data
Supplementary data to this article can be found online at
https://doi.org/10.1016/j.energy.2020.117427.
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