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16Оценка энергетической безопасности Кореи и Японии
Ён Юнг Мин
соискатель, Московского государственного университета им. М.В, Ломоносова, научный сотрудник Азиатско-Тихоокеанского исследовательского центра, университет Ханьян (Сеул), yoonym81@gmail.com
Энергетическая безопасность является одним из главных приоритетов в странах-импортерах энергоносителей и одним из наиболее активно исследуемых предметов, связанных с энергетическими проблемами в академической сфере. Однако существующие исследования затрудняют описание и оценку уровня развития или степени энергетической безопасности в конкретной стране. В случае Кореи и Японии понимание и оценка уровня или степени энергетической безопасности на практике имеют важное значение с учетом их условий. В данной статье дается обзор последних исследований по данной теме и приводится простая, но практичная индексная система для оценки энергетической безопасности Кореи и Японии. Используется метод анализа содержания, индекс разнообразия Шеннона-Винера и метод нормализации Индекс энергетической безопасности и его субиндексы Кореи и Японии были изменены с аналогичными закономерностями, но в то же время они демонстрируют разные черты по отношению друг к другу. Подтверждено, что развитие отечественных источников энергии является наиболее важным для повышения энергетической безопасности и российские энергоресурсы сыграли определенную роль в повышении энергетической безопасности Кореи и Японии.
Ключевые слова: энергетическая безопасность, энергетический сектор Кореи и Японии, энергетическое разнообразие, энергетическая стабильность, экономическая целесообразность энергоснабжения
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Introduction
Ensuring energy security is one of the top priorities in countries depending on imports for the energy supply in the national economy. Stable supply of energy resources is critical not only for economic growth but also for the routine life of the people and national security. This article tries to make an index system assessing energy security and applies it to Korea and Japan, which are the representative countries seeking improvement of energy security due to their deficit of endowed energy resources. Korea and Japan are 2 of the top energy-consuming and importing countries in the global energy market. Moreover, their dependency on imports in the energy supply is at the highest level. Since 2000, the import dependency of these countries has been about 80% and it has been increasing. Therefore, understanding and assessing the level or degree of energy security in practical ways in those countries have significance not only for academic analysis but also for making energy policies. Academic reflections on energy security date back to the 1960s and came of age with the oil crises of the 1970s [1]. There are diverse works on the subject in both theoretical and practical ways, but they are not enough to describe and assess the level or degree of energy security in a specific country. Studies with theoretical approaches provide us a conceptual framework for the questions about what indicators we take and how to categorize them to make index assessing energy security. However, as Ang et al. indicate, there is no widely accepted definition of energy security[2] and it has different meanings to different people at different moments in time[3]. Some practical studies aiming evaluation of energy security also exist. However, in overall, they are designed for the international comparison rather than deepen analyzing degree and trend of energy security in countries that have an extremely high dependency on imported energy resources. Therefore, in this article, we briefly overview recent studies on the subject and based on it, make a simple but practically useful index system for assessing energy security of Korea and Japan.
Literature review
A. Cherp & J. Jwel [1] conduct content analysis on the concept of energy security. The authors summarize the historic features and context of energy security as well as review the 4 As (Availability, Affordability, Accessibility, and Acceptability), which is the major conceptual framework for the study of energy security. In addition to this, the article reviews the recent conceptual development concerning energy security. Yao & Chang [4] estimates China's energy security using 4-As framework consisting of availability, affordability, and acceptability. Unlike other studies on this subject, the author gives focus on the internal factors affecting the energy security of China, so the stability of the energy system is analyzed at a limited range. Jansen & Seebregts [5] also review recent approaches towards measuring the extent of long-term energy security and security externality valuation. The article gives a deep and
critical analysis of the representative 2 approaches of energy security, which are diversity-based indices and the Supply/Demand Index. Sovacool & Brown [6] try to assess the energy security of the USA and 21 OEcD countries based on 4 dimensions of energy security, which re is composed of availability, affordability, efficiency, and environmental stewardship. The article creates an energy security index, utilizing 10 indicators that encompass economic, social, political, and environmental aspects of energy security, and analyzed the status of energy conditions in 22 OECD countries from 1970 to 2007. Loschel et al [7] try to reclassify indicators of assessing energy security in existing studies on the subject with an additional dimension, which are ex-post and ex-ante indicators. The ex-post indicators are mostly based on price developments and the ex-ante indicators are to a greater extent aimed at illustrating potential problems. The article suggests the necessity of including market structure and political stability of exporting countries for the development of assessing energy security. Kruyt et al. [8] distinguish four dimensions of energy security that relate to the availability, accessibility, affordability, and acceptability of energy and classified indicators for energy security according to these categories by analyzing available indicators for the long-term security of supply. Jang et al.[9] estimate energy security by a comparative analysis of South Korea and other OECD countries in terms of energy diversity (fuel diversity). The article also employs the representative framework for analyzing, which is 4 As but very focused on the concept of accessibility. As a proxy of the accessibility, the authors use fuel diversity to estimate a measure of energy security.
Developing energy security index
Energy security is a concept focused on energy consumers or importers. The IEA defines energy security as "the uninterrupted physical availability at a price which is affordable, while respecting environmental concerns [10] " and defines energy security as the security of supply of energy resources. The World Energy Council defines energy security as "availability of local and imported resources to meet the growing demand for energy over a period of time and at affordable prices"[11]. In other words, energy security is the question about stable energy supply from reliable suppliers at affordable prices. The stability can be divided into the diversity in sources and stability in supply structure. The stability in the source can be expressed in terms of diversity. High dependency on a specific energy supplier or energy source, i.e. low diversity, has an increased impact of the individual supplier or energy sources on the energy system and increases risk. In the case of energy importing countries, the diversity of energy importing routes represents the stability of the energy supply structure. The more an energy system imports from the more diverse energy resource suppliers, the more stable the supply structure will be by being free from the influence of individual suppliers. The stability of the energy supply structure by sources can also be evaluated in the same way through supply diversity of the primary energy sources. As energy demand is perceived as a component of energy security[12], it is argued that reducing energy consumption and dependency will increase energy securit [13]. The stability in supply structure refers to the degree of how a country has a stable energy supply chain. It can be evaluated by the stability of importing major energy resources and energy import dependency. The last aspect that constitutes energy
security is the economic feasibility of energy supply costs. The economic feasibility of energy supply costs indicates that a country pays the appropriate cost in order to supply energy to its economy. In our study, this is expressed as energy import cost to GDP. Based on these conceptual bases, the energy security of an energy importing country can be express as follows.
55C. = SD + SS + EF
Eq. 1.
Energy security consists of the system diversity, system stability, and economic feasibility of the national energy system. First, the system diversity is defined as follows.
SD (System Diversity) = f^siS^ Eq 2.
The diversity of the energy system means how many different energy sources are supplied through various supply routes to the total energy supply of individual countries. Therefore, energy system diversity basically consists of import diversity of energy import and diversity of energy mix. We will use Shannon-Wiener's Diversity Index to measure the diversity of energy imports and the diversity of the energy mix. Shannon-Wiener's diversity index, which is used to measure species diversity in an ecosystem in ecology, represents the diversity of the entire ecosystem, taking into account both the share of species and their relative proportions. Here we can measure energy import diversity and energy mix diversity by replacing the ecosystem with the energy import structure and the TPES (i.e., energy mix) of the country i, and replacing individual species with energy exporting countries and individual primary energy sources. Shannon-Wiener's Diversity Index is modified to show the energy import diversity Dtrade and the energy mix diversity as follows.
Where,
Pj. import diversity of energy resource j =
If Stloga sO ■ logjTft)
— Zfs! import diversity of energy resource j at country level
s,: share of exporting country i in total import of energy resource j
— StT'f¿l°giTVL: import diversity of energy resource j at the regional level
rf: share of exporting region i in total import of energy resource j
fcij: Share of energy resource i in TPES
D
swppfj
= -Efm&gj^
Eq. 4.
Where,
?v Share of energy resource i in TPES
Next, the stability of the energy system measures how stable the supply structure of an individual country's energy system is. The supply of energy to the national economy can be roughly divided into domestic production and imports. Our study assumes that the supply stability of domestic production energy is complete. Thus, the concept of the stability of the energy system can be defined as how a small share of energy to the total demand a country imports from how many reliable exporters [9]. Energy import stability assesses the stability of crude oil and natural gas import routes and is expressed as follows.
SS (System Stability)
(uMSTRaiI+uss,STRgas) ■ (1 - ID^rt) Eq.
5.
STBBli = Zi=L(Ci-lPJiw! ■ CRlSKhQi! ■ SHAREhM) Eq. 6.
CHPKhgl!: Chokepoint score of oil-exporting country/'
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CZlir'; ....; : Country risk of the oil-exporting country I
StiAREj Bj[ : share of exporting country i in total oil import
: the relative share of oil in TPES STB^ = Zf=i(CHPKhgas- CRlSK,ffas-SHARE,gas) Eq. 7.
CHPK^gga : Chokepoint score of gas exporting country/' i.-S.'i.v ....: Country risk of gas exporting country i SHARE,sas : share of exporting country i in total gas import
In this section, the energy security of Korea and Japan is assessed based on the above-designed index. Energy diversity of Korea and Japan
iiflr
: the relative share of gas in TPES
The stability of import routes of crude oil and gas is represented by the weighted sum of the country risk and choke-point score of each exporting country, weighted by energy independence. The detailed calculation method is described in the next section together with the actual data.
The economic feasibility of energy supply refers to the relative cost of energy supply considering the economic performance at the national level. The supply of energy is one of the most basic inputs to operate the national economy. Therefore, it can be said that the energy resources supplied to the energy system at the national level are basically used for the production of goods and services. Roughly speaking, the supply of energy can be divided into the domestic energy supply and imported energy resources. We will only consider the cost of supplying the imported energy resources here. It is difficult to identify the supply cost of domestic production energy, and it is meaningless in Korea and Japan. For similar reasons, we consider here only the cost of supplying primary energy. Once the primary energy source is supplied, it can be seen that the transformation process and the result are already added to the production activities in the national economy. Therefore, we will use the inverse ratio of energy import cost to economic performance, that is, the share of energy import cost to GDP, as a proxy variable to evaluate the economic feasibility of energy supply costs. The last issue to be considered here is the distortion of economic efficiency due to dependency on energy imports. For example, if import dependency is close to 90%, as in Japan, the energy import cost to gDp will be close to the total energy supply cost, that is, the energy intensity. On the other hand, if import dependency is around 10%, dependency on imported energy will be very low compared to total energy supply cost. The problem, however, is that GDP includes value-added production from domestic production energy supply. In other words, the ratio of import costs to GDP, which does not take into account dependency on energy imports, can be overestimated or underestimated depending on the import dependency of individual countries. Therefore, we use here an index of energy import cost-to-GDP adjusted by import dependency to show the economic feasibility of energy supply cost as shown in Eq. 7..
EF (Economic Feasibility) = 1 - ^st ■ IDtmpaTt Eq.
total cost for energy import
= eimpt.pc
ivi.y." • total volume of energy import per capita euse_pc: energy consumption per capita Assessing the energy security of Korea and Japan
7.
Figure 1. Composite energy import diversity index of Korea and Japan
Source: Author
The energy import diversity of Korea and Japan is evaluated as Eq.3. above using Shannon-Wiener's diversity index. This is the composite energy import-diversity index as the sum of diversity indices of individual sources weight by their share in TPES. In other words, we calculated the composite index reflecting the relative importance of individual energy sources in the energy mix to the diversity index. For the details, see Yoon [14].
Table 1
Coal Oil Natural Gas Nuclear RES
Kor Jap Kor Jap Kor Jap Kor Jap Kor Jap
2000 22.2 18.4 52.0 49.9 9.8 13.7 14.1 12.9 1.8 5.0
2001 23.0 19.1 50.6 48.2 10.5 14.0 14.1 12.7 1.8 6.0
2002 23.5 19.7 49.1 48.5 11.1 14.3 14.3 11.5 2.0 5.9
2003 23.8 20.4 47.6 48.5 11.2 15.1 15.1 9.4 2.3 6.5
2004 24.1 21.8 45.7 46.3 12.9 14.7 14.8 10.9 2.5 6.3
2005 24.0 20.9 44.4 46.5 13.3 14.9 16.1 11.8 2.3 5.9
2006 24.3 21.1 43.6 44.5 13.7 16.4 15.9 11.6 2.4 6.4
2007 25.2 21.9 44.6 44.4 14.7 17.8 13.0 10.1 2.5 5.9
2008 27.4 22.5 41.6 42.7 14.8 18.4 13.5 10.3 2.7 6.1
2009 28.2 21.0 42.1 42.1 13.9 19.1 13.1 11.5 2.8 6.3
2010 29.2 22.6 39.5 40.1 16.3 19.2 12.1 11.3 2.8 6.8
2011 30.2 22.0 38.0 43.1 16.7 23.3 11.7 4.2 3.0 7.4
2012 29.1 23.4 38.1 44.3 18.0 24.5 11.4 0.7 3.5 7.2
2013 29.2 25.1 37.8 42.7 18.7 24.2 10.4 0.4 3.8 7.5
2014 29.9 24.4 37.1 44.6 16.9 23.6 11.7 0.0 4.5 7.5
2015 29.7 24.6 38.1 44.7 15.2 22.3 12.1 0.4 4.9 8.0
Source: Statistical bureau of Korea, Statistical Bureau of Japan
Using Shannon-Wiener's diversity index [15] as in Eq. 4., the energy mix diversity index could simply be calculated. As Table 1. shows, the dominant source in both countries is oil, which takes approximately 40%.
The calculated energy mix diversity turns out as follows in Figure 2.. The index of Korea has increased since 2000. The major factor affecting the improvement is losing the share of the dominant source, which is oil. As a result, the gap among the sources has been smaller and it brings the increase of the index. By 2011, Japan has shown a similar trend to that of Korea at a higher level. However, the freezing of all nuclear reactors due to the Fukushima crisis in 2011 dragged the index down. The dominant source, which is oil, still has almost half of the TPES. From the viewpoint of diversity, the higher share of the dominant
source and the absence of a source gives significant damage to the structural soundness of TPES.
Figure 2. Energy mix diversity index of Korea and Japan Source: Yoon for Korea, calculated by the author for Japan
Figure 3. shows the results of the composite energy system diversity index of Korea and Japan calculated by Eq. 2.. Korea's energy system diversity index is higher than that of Japan in the period.
the transition of TPES composition from imported fossil energy resources to the RES has significance not only for the diversity of energy mix but also for the stability of energy supply.
Import stability is measured by the import stability of oil and natural gas. The chokepoint score is the number of chokepoints that the imported oil and gas pass through from an exporting country 'A' to an importing country. The score turns out as follows.
„„„„ „ ,Nwmt?r of passing Chckepohiti. _ „
Eq. 9.
The country risk of exporting countries is calculated based on the OECD Country Risk Classification. The country risk score was calculated in order to the low-risk countries could have a higher score. The detailed description is available at Yoon. In overall, the stability index of the energy system of Japan has shown a higher value than that of Korea by 2010. In 2011, the index of Japan dropped significantly and it is still lower than that of Korea. Considering that the composite import stability index of Japan has been higher than that of Korea since 2000, the cross of the indices is due to the increase of energy import dependency of Japan.
Figure 3. Energy system diversity index of Korea and Japan Source: The author
The stability of the energy system
Figure 4. Energy import dependency of Korea and Japan, % Source: Statistical bureau of Korea, Statistical Bureau of Japan
This article adopts the method and result of Yoon. Therefore, here notice that this part has the summarized content of the previous work. The stability of the energy system consists of import stability and stability of domestic energy supply as seen in Eq. 5.. The higher the dependency on imports, the more likely it will be affected by changes in the international energy market. Thus, dependency on energy imports is the most fundamental indicator for estimating the stability of energy systems. The dependency of Korea has a relatively stable trend since 2000. The import dependency of Japan also has been stable at the 80% range by 2010. However, since 2011 when the crisis occurred, the dependency has risen by late 80%. The dependency in both countries coincides with the share of fossil energy sources in TPES, which means that
Figure 5. The stability index of the energy system and its sub-stability indices Source: Yoon, the author
The economic feasibility of energy supply
As Eq.7. indicates, the economic feasibility of energy supply can be measured by the total import cost of energy resources, GDP, and energy dependency. The energy import cost is measured by using the imported value of oil, natural gas, and coal in USD. In 2000, the import cost of Korea was about 32 billion USD and reached to about 158 billion USD in 2012. In the same period, the cost of Japan increased from 67 billion USD to 270 billion USD. Figure 7. shows the trend of the economic feasibility of energy supply costs of Korea and Japan. Since 2000 Japan has higher economic feasibility than that of Korea and after 2002 the gap between them became bigger by 2014. The increase in the gap is due to the declined feasibility of Korea. Although there was some fluctuation, the Japanese feasibility index has a relatively stable trend comparing to that of Korea. On the other hand, the feasibility index of Korea has shown the declined trend since 2002 for 10 years with a relatively high range of fluctuation as seen in Figure 7. below.
Let's assess the energy security index by combining the sub-indices individually measured as above. The diversity of the energy system was calculated by simply averaging the energy import diversity index and the energy mix diversity index without applying the weight value. First of all, we need to normalize sub-indices. Since the absolute level of each index is different, if the normalization is not
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carried out, there might be an unintended weight. In our study, all the sub-indices have equal importance. It is therefore important to eliminate the unintended weighting effect of the unit of measure. We will convert all three subindices to values between 0 and 1 using the simplest and most commonly used Max-Min normalization. The average of the normalized sub-indices is the value of the energy security index. The trend of the index in Korea and Japan calculated in this way is shown in Figure 8.
130,0
160,0
i K_oil_imptc ■ K_gas_impte
K_a>al_irnpcc
Figure 6. The energy import cost of Kore and Japan, billion USD Source: UN Comtrade
The energy security index of Korea and Japan show a similar trend. They have shown slowly declining trend by 2008 and had rapid drop & recovery trends by 2015 after a temporal rebound in 2009. However, the level of the index value of Japan has been higher than that of Korea by 2014. This gap in the level of index value was reversed in 2015 for the first time since 2000. As seen in Figure 8., the energy security indices of Korea and Japan are strongly affected by the international energy price. This feature turns out stronger in Korea because the economic feasibility index of the energy supply of Korea is more sensitive to price factor as we've seen in Figure 7.
Figure 7. Economic feasibility of energy supply of Kore and Japan Source: UN Comtrade
Figure 8. Energy security index of Korea and Japan Source: The author
Conclusion
We assessed the level of energy security of Korea and Japan by creating an index that can evaluate energy security based on existing studies and the conventional definition of energy security. The energy security index and its sub-indices of Korea and Japan have been changed with similar patterns, but at the same time, they show different features to each other. Based on the results, we have the following implications. First, the most significant factor for improving the energy security of a country is developing domestic energy sources. It is so obvious and common sense, but by changes in the energy security index and its sub-indices, we could see the significance of such obvious factors once again. Second, from the viewpoint of developing domestic energy sources, policies of Korea and Japan on nuclear energy and RES(Renewable Energy Sources) have importance and difficulty at the same time. One of the biggest reasons for the decrease in the energy security index of Japan is the freezing of all nuclear reactors in 2011 due to the accident in Fukushima. After the accident, the government closed down the reactors and the share of nuclear energy in TPES, which reached 11% in 2011, never recovered by this end. Meanwhile, Korea has a plan to reduce the share of nuclear energy and to increase the share of RES in its energy mix. According to the "3rd National Energy Master Plan" of Korea, the share of nuclear energy will be decreased by shutting down old reactors and by not building new reactors. In other words, both countries have difficulty to increase the share of nuclear energy or even they are trying to reduce the share of nuclear energy and compensating the share by the development of RES. The matter is that the development of RES at the level just compensating the reduced share of nuclear energy is not able to contribute to the improvement of energy security and the development of RES over the compensating the reduce the share of nuclear energy is a quite tough task to be achieved in the mid-term. Therefore, Korea and Japan
need to consider carefully what impacts the policies on nuclear energy and RES. Third, Russian energy resources have played a role in the improvement of energy security in Korea and Japan. As we've seen in Figure 3., the energy system diversity index of Korea and Japan had increased significantly from 2009 to 2012. On such improvement of energy security index increase in import of Russian oil and import of Russian natural gas that began in 2009 has given a positive impact. According to UN Comtrade data, in Korea the share of Russian oil in total oil import has increased from 3.2% in 2009 to 6.0% in 2015 and in the same period oil import diversity has grown 1.232 to 1.602. The share of Russian natural gas in total natural gas import also has grown 3.2% to 6.9% in the same period and the gas import diversity index has increased from 2.635 to 2.956. In the case of Japan, the share of Russian oil in the total oil import has significantly increased from 3.13% to 12.05% in the same period and the oil import diversity index has significantly improved from 0.790 to 2.445. the share of Russian natural gas in total gas import also has increased from 3.64% to 8.1% and the diversity index has improved from 2.062 to 2.578. It is hard to say that such improvement in the diversity indices is due to the only increase in the import of Russian energy resources in Korea and Japan. However, it's obvious and hard to deny that an increase in the import of Russian oil and gas and the decrease in the relative share of Middle East countries have significantly contributed to the improvement of the energy security index in Korea and Japan by increasing the diversity indices. Therefore, it is necessary for Korea and Japan to actively consider expanding the import of fossil fuel energy resources from non-Middle East regions such as Russia, the USA, South America, and Central Asia.
Assessing Energy Security of Korea and Japan Yoon Youngmin
Hanyang University
Energy security is one of the top priorities in energy importing countries and one of the most actively researched subjects related to energy issues in the academic sphere. However, the existing studies have difficulty to describe and evaluate the development level or degree of energy security in a specific country. In the case of Korea and Japan, understanding and assessing the level or degree of energy security in practical ways have significance considering their conditions. This article gives an overview of recent studies on the subject and makes a simple but practical index system for assessing the energy security of Korea and Japan. Method contents analysis, Shannon-Wiener's diversity index, and method max-min normalization are employed. The energy security index and its sub-indices of Korea and Japan have been changed with similar patterns, but at the same time, they show different features to each other. It is confirmed that the development of domestic energy sources is the most important for improving energy security and Russian energy resources have played a role in the improvement of energy security in Korea and Japan.
Keywords: energy security, the energy sector of Korea and Japan, energy diversity, energy stability, economic feasibility of energy supply
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