economic growth, energy demand and the environment ... · transportation have lead to an unexpected...
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Economic Growth, Energy Demand and the Environment –
Empirical Insights Using Time Series and Decomposition Analysis
Dirk C. Böhm
Bibliografische Information Der Deutschen BibliothekDie Deutsche Bibliothek verzeichnet diese Publikation in der Deutschen Nationalbibliografie; detaillierte bibliografische Daten sind im Internet über www.dnb.de abrufbar.
Als Inaugural-Dissertation zur Erlangung des Grades eines Doktors der Wirtschaftswissenschaften (Dr. oec.) an der Universität Hohenheim 2010, Fakultät Wirtschafts- und Sozialwissenschaften, vorgelegt von Dirk C. Böhm. D 100
Erstgutachter: Prof. Dr. Ansgar BelkeZweitgutachter: Prof. Dr. Michael AhlheimPrüfungsvorsitzender: Prof. Dr. Werner F. SchulzDatum der mündlichen Prüfung: 07. 02. 2011
Gedruckt auf holz- und säurefreiem Papier, 100 % chlorfrei gebleicht.
©Weißensee Verlag, Berlin 2011www.weissensee-verlag.de
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Umschlagbild: Peter Elvidge (pixmac.com)
Printed in Germany
ISBN 978-3-89998-193-3
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Contents
Abbreviations ................................................................................................................�����
List of Figures ..............................................................................................................�X����
List of Tables ................................................................................................................��X��
1.� Preface ....................................................................................................................... 1�2.� Energy and the Economy .......................................................................................... 7�
2.1� The Current Energy System ............................................................................... 7�2.2� Resources and Reserves of Fossil Fuels: Limits to Growth? ........................... 11�2.3� Growth and the Environment: The Environmental Kuznets Curve ................ 18�
3.� The Relationship between Energy Prices, Energy Consumption and Growth ........ 23�3.1� Granger Causality ............................................................................................ 23�3.2� Cointegration and Vector Error Correction Models ........................................ 27�
3.2.1� Individual Unit Root Test ......................................................................... 28�3.2.2� Testing for Cointegration ......................................................................... 28�3.2.3� Panel Unit Root and Cointegration Tests ................................................. 29�3.2.4� Causality Tests .......................................................................................... 31�
3.3� Empirical Evidence of Causal Relationships ................................................... 37�3.3.1� Causality between Energy Consumption and Economic Growth ............ 37�3.3.2� The Role of Energy Prices ........................................................................ 44�
3.4� Mutual Causality and Heterogeneity ............................................................... 50�4.� The Impact of Energy Use on the Environment ...................................................... 53�
4.1� Introduction: The Kaya Identity and the Concept of Decomposition .............. 53�4.2� The Decomposition of CO2 Emissions............................................................. 57�4.3� Which are the Factors behind Emission Changes? .......................................... 62�4.4� How to Achieve Emission Reductions: An Aggregated View ........................ 72�
5.� Industrial Energy Demand and Emissions .............................................................. 75�5.1� Introduction: The Role of the Industry Sector ................................................. 75�5.2� Index Decomposition Analysis for the Industrial Sector ................................. 77�5.3� Energy and CO2 Efficiency in the European Manufacturing Sector ............... 81�
5.3.1� Decomposition of Changes in Energy Consumption ............................... 81�5.3.2� Decomposition of Changes in CO2 Emissions ......................................... 86�
5.4� Energy Productivity Gains in the Manufacturing Sector ................................. 92�6.� The Transport Sector ............................................................................................... 95�
6.1� The Need for Mobility and the Dependence on Oil ......................................... 95�6.2� A Short Decomposition Analysis of CO2 Emissions in the Transport Sector 100�6.3� Drivers of Road Transport Energy Demand and CO2 Emissions .................. 105�6.4� The Future of Transport Energy Use ............................................................. 109�
7.� Conclusions ........................................................................................................... 113�7.1� Summary ........................................................................................................ 113�7.2� Outlook .......................................................................................................... 116�
References .................................................................................................................... 119�
Abbreviations
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Abbreviations
ADF test Augmented Dickey Fuller test
AIC Akaike Information Criterion
APEC Asia-Pacific Economic Cooperation
ARDL Autoregressive Distributed Lag
AUS Australia
AUT Austria
BEL Belgium
BGD Bangladesh
BGR Bulgaria
BGR Bundesanstalt für Geowissenschaften und Rohstoffe
(Federal Institute for Geosciences and Natural Resources)
bn Billion
BRA Brazil
BTU British Thermal Units
C CO2 Emission Coefficient
CAN Canada
CE Cointegrating Equation
Ceff Emission Coefficient Effect
CHE Chemical and Petrochemical Industry
CHN People's Republic of China
CO Carbon Oxide
CO2 Carbon Dioxide
CYP Republic of Cyprus
CZE Czech Republic
DEU Germany
DNK Denmark
e Natural logarithm of per capita total final energy demand
E Total Energy Consumption in the Industry sector
Eact Activity Effect (Energy Consumption)
ECM Error Correction Model
ECMT European Conference of Ministers of Transport
ECT Error Correction Term
Eint Intensity Effect (Energy Consumption)
Abbreviations
V���
EKC Environmental Kuznets Curve
EM CO2 Emissions from the Consumption of Fossil Fuels
EMact Activity Effect (CO2 Emissions)
EMemf Emission Factor Effect
EMint Intensity Effect (CO2 Emissions)
EMmix Fuel Mix Effect
EMstr Structure Effect (CO2 Emissions)
EOR Enhanced Oil Recovery
ESP Spain
Estr Structure Effect (Energy Consumption)
ET Total CO2 Emissions from the Transport Sector
EU European Union
EUR19 Aggregate of 19 European Union and OECD members
(Germany, France, Great Britain, Italy, Spain, the Netherlands,
Poland, Belgium, Sweden, Austria, the Czech Republic, Finland,
Greece, Portugal, Hungary, Denmark, Ireland, Slovakia,
Luxemburg)
EUR23 Aggregate of 23 European Union members
(Germany, France, Great Britain, Italy, Spain, the Netherlands,
Poland, Belgium, Sweden, Austria, the Czech Republic, Romania,
Finland, Greece, Portugal, Hungary, Denmark, Ireland, Slovakia,
Bulgaria, Luxemburg, Cyprus, Malta)
FIN Finland
FM Fuel Mix Variable
FMeff Fuel Mix Effect
FOD Food and Tobacco Industry
FPES Primary Energy Supply of Fossil Fuels
FRA France
FSU Former Soviet Union
FSUREG Region of the Former Soviet Union (= FSU)
G-11 Group of Eleven (Jordan, Croatia, Ecuador, Georgia, El Salvador,
Honduras, Indonesia, Morocco, Pakistan, Paraguay, Sri Lanka)
G-7 Group of Seven
(The United States, Japan, Great Britain, Germany, Canada,
France and Italy)
GBR Great Britain
GCC Gulf Cooperation Council
Abbreviations
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GDP Gross Domestic Product
GHG Greenhouse Gas
GRC Greece
HUN Hungary
I Energy Intensity
IBRD International Bank for Reconstruction and Development
IDA Index Decomposition Analysis
IDN Indonesia
IEA International Energy Agency
Ieff Energy Intensity Effect
IND India
IPCC Intergovernmental Panel on Climate Change
IPS test Im, Pesaran and Shin panel unit root test
IRL Ireland
IRN Islamic Republic of Iran
IRS Iron and Steel Industry
ITA Italy
JAMA Japan Automobile Manufacturers Association
JPN Japan
KOR Republic of Korea (South Korea)
LLC test Levin, Lin and Chu panel unit root test
LMDI Log Mean Divisia Index
LNG Liquefied Natural Gas
LPG Liquefied Petroleum Gas
LR Long Run
LUX Luxemburg
MAC Machinery Industry
MAIC Modified Akaike Information Criterion
MET Non-Ferrous Metals Industry
MEX Mexico
M Fuel Mix Variable
MLT Malta
MS Modal Split
Abbreviations
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MSeff Modal Split Effect
Mt Million Tons
MWI Malawi
MYS Malaysia
NLD The Netherlands
NMM Non-Metallic Minerals Industry
NOx Nitrogen Oxide
NZL New Zealand
OECD Organisation for Economic Co-operation and Development
OPEC Organization of Petroleum Exporting Countries
p Natural logarithm of the index of real energy prices for industry
and households
PAK Pakistan
PAP Paper, Pulp and Printing Industry
Peff Population Effect
PHL Philippines
pkm Passenger kilometres
POL Poland
POP Population
PP test Phillips-Perron unit root test
PPP Purchasing Power Parity
PRT Portugal
Q Activity Level
R/P ratio Reserves-to-Production ratio
RAR Reasonably Assured Resources
ROU Romania
S Share of Fossil Fuels; Activity Share
SAU Saudi Arabia
Seff Substitution Effect
SGP Singapore
SIC Schwarz Information Criterion
SO2 Sulfur Dioxide
SPM Suspended Particulate Matter
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SR Short Run
STAN Structural Analysis Database (OECD)
SVK Slovak Republic
SWE Sweden
t Tons
TEX Textile and Leather Industry
TFC Total Final Consumption
THA Thailand
tkm Thousand Kilometres
TPES Total Primary Energy Supply
TRA Transport Equipment Industry
TUR Turkey
TWN Taiwan
U.S. United States
UK United Kingdom
UNFC United Nations Framework Classification for Fossil Energy
and Mineral Resources
US United States
USA United States of America
USD U.S. Dollars
VA Value Added
VAR Vector Autoregression
VECM Vector Error Correction Model
vkm Vehicle Kilometres
VMT Vehicle Miles Travelled
WBCSD World Business Council for Sustainable Development
WEO World Energy Outlook (IEA Publication)
WOD Wood and Wood Products Industry
y Natural logarithm of real per capita GDP
Yeff Income Effect
ZAF South Africa
Preface
1
1. Preface
Industrialization and increasing wealth in emerging markets – especially in China
and India – as well as intensifying globalization and the associated boost in
transportation have lead to an unexpected rise of global energy demand in the last
decade. According to the Reference Scenario in the 2007 issue of the IEA World
Energy Outlook, the global primary energy demand is projected to grow by 55%
between 2005 and 2030. The developing countries with fast growing populations
contribute 74% of this increase, China and India alone 45%.1 The bulk of global
energy supply is coming from fossil fuels. Although renewable energy sources
are promoted heavily in industrialized countries, they will neither be able to
replace fossil fuels, nor fill the gap between growing demand and the current
level of supply of fossil resources in the near future. This has important
implications for the world’s energy security. We will see a growing dependence
of consuming countries on oil and gas imports as well as a reduction of
geographic supply diversity with an increasing market dominance of the Middle
East and Russia. As a geopolitical consequence, energy will greatly determine
foreign relations in the future as the uninterrupted flow of energy will mainly
depend on the political and economic stability of the producer regions.
Furthermore there will be more competition among consumer countries for
energy supplies following this growing energy import dependency. Another
consequence of the soaring demand in combination with the existing global
energy mix is accelerating climate change due to increasing greenhouse gas
emissions. According to the Intergovernmental Panel on Climate Change Fourth
Assessment report2, most of the observed rise in global average temperatures
since the mid-20th century is very likely3 related to the increase in anthropogenic
greenhouse gas (GHG) concentrations. The combustion of fossil fuels is the
largest contributor to GHG emissions and carbon dioxide (CO2) is responsible for
about 95% of the energy-related emissions. Thus fossil fuel combustion is the
single largest human influence on climate. While emissions have doubled in the
period between 1971 and 2005, real gross domestic product (GDP) has reached
three times the value of the base year (see Figure 1). But although declining
global CO2 emissions per unit of GDP could be observed in many industrialized
countries, strong economic growth in emerging markets has led to a worrying 1 See IEA (2007b), p.73. 2 IPCC (2007) 3 In the IPCC terminology “very likely” means a likelihood of occurrence of > 90%.
Preface
2
rise in global CO2 emissions in the last years. Similar to the supply security
problem GHG emissions can be tackled by either increasing the share of
renewable energy sources or by the implementation of strict energy conservation
measures as well as efficiency technologies. During the negotiation process for a
new post Kyoto climate regime energy saving measures play a vital role, as
energy saving is far easier in the short term than restructuring the primary energy
mix. However a lot of countries, mostly developing countries, fear that such
policy measures will harm their economic development.
Figure 1: World CO2 emissions from fuel combustion and real GDP4
Since the oil crisis of the 1970’s the relationship between energy consumption,
environmental pollution and economic growth has been analyzed and discussed
in many different ways. Especially between 2004 and 2008 energy became an
issue once again as global economic growth led to an enormous increase in oil
prices.
The IEA World Energy Outlook 2006 stated: “The world is facing twin energy-
related threats: that of not having adequate and secure supplies of energy at
affordable prices and that of environmental harm caused by consuming too much
of it. …” and “…the need to curb the growth in fossil-energy demand, to increase
geographic and fuel-supply diversity and to mitigate climate-destabilising
emissions is more urgent than ever.”5 In the very same year Sir Nicholas Stern
published his widely acknowledged and discussed “Stern Review on the
Economics of Climate Change”6, presenting scientific evidence for the economic
4World GDP in 2000-USD using Purchasing Power Parities (PPP). 5 See IEA (2006), p.37. 6 Stern (2006).
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Data Source: IEA; author’s own illustration.
Preface
3
impacts of climate change and necessary policy responses. The subsequent IEA
World Energy Outlook 2007 focused on the role of China and India as the
“emerging giants of the world economy and international energy markets.”7 It
became clear that the growth rates of these countries and the impact on global
energy demand would pose a big challenge to the present energy system and
existing efforts to combat climate change. Thus a transition to a more secure,
lower-carbon energy system seemed inevitable, but only without the risk of
undermining economic and social development. Furthermore, soaring energy
prices fueled the fear of a recurrence of the oil crisis of the 1970s and reports
about continuous resource depletion led to a revival of the peak oil theory
initially developed by Marion King Hubbert in the 1950s.8
These developments and discussions were the starting point for this text. The
idea was to dig deeper into the mechanisms of energy use and economic
development and to assess which are the main factors behind energy savings and
a reduction of energy related carbon dioxide emissions. As discussed in detail in
the following chapters, the existing empirical literature only gives a limited view
on these issues as to the methods used, to the geographical and sectoral coverage,
as well as the time periods observed. This thesis thus aims at empirically giving
insights about the relationship between energy consumption, economic growth
and CO2 emissions on a global scale. The analysis is carried out for the top
energy consumers and CO2 emitters worldwide with a special emphasis on the
European Union and some focus countries for the detailed investigation of the
industry and transport sector. In addition, recent panel cointegration and
decomposition methods are used to analyze detailed data of the last 25-35 years.
The statements or assertions below are to be tested within this context:
- There is a mutual interrelationship between economic growth and energy
demand.
- Developing and emerging economies are more energy-dependent than the
economies of highly developed countries.
7 See IEA (2007b), p.41. 8 See Hubbert (1956).
Preface
4
- Rising energy productivity in combination with changes in the primary
energy mix with less carbon content is the best strategy to mitigate energy
related emissions.
- The reduction of CO2 emissions within the industrial sector in Western
European countries was only possible due to a relocation of energy
intensive subsectors to developing and newly industrialized countries.
The text is structured as follows. Chapter 2 gives a description of the relationship
between energy, economic growth and the environment. The current energy
system in terms of availability and use of energy sources is illustrated. The
question is discussed, whether pollution is rising inevitably with economic
growth, or if emissions fall again at a certain level of per capita income
(Environmental Kuznets Curve).
In Chapter 3 the causality between energy prices, energy consumption and
economic growth is analyzed empirically. This empirical investigation applies
cointegration and error correction techniques and consists of two parts. In the
first part the bivariate relationship between energy and GDP is examined for the
15 biggest global energy consumers between 1978 and 2005. In the second part,
energy prices are added as a third variable.
Chapter 4 uses decomposition analysis of the change in carbon dioxide emissions
in order to analyze the relationship between emission growth and changes in
underlying factors using the Log Mean Divisia Index (LMDI) method. It covers
the biggest carbon dioxide emitting countries and regions that together account
for over 80% of total emissions worldwide in the period from 1971 to 2005.
The industry sector is one of the largest consumers of energy and also one of the
largest energy-related CO2 emitters. Chapter 5 gives insights into the
mechanisms of change in industrial energy consumption as well as changes in
CO2 emissions for ten manufacturing industries in five European countries by
using the same decomposition technique.
The transport sector is one of the largest and fastest growing sources of
greenhouse gas emissions. As a consequence Chapter 6 provides an overview of
energy consumption and emission drivers in the transport sector, with empirical
examples for the United States, Japan and Germany. The second part of the
Preface
5
chapter focuses explicitly on road transport, as this sub-sector has the lion’s share
of transport energy use and emissions.
Finally Chapter 7 summarizes the empirical results and presents policy
implications as well as further need for research beyond the scope of this text.
This thesis uses recent panel cointegration and error correction models to test for
causality between energy consumption and economic growth. It also assesses the
role of energy prices in this context using real indices of energy prices for
industry and households, while most other studies on this issue use consumer
price indices as a proxy. In chapters four to six a perfect index decomposition
method LMDI1 is applied to analyze the underlying factors of energy
consumption patterns and CO2 emissions. Time series decomposition is used
because the decomposed results given by this approach can better explain the
underlying mechanisms of change in energy use. Most other decomposition
studies of energy consumption and CO2 emission use period wise decomposition,
which is based on the data of two benchmark years, and the data for the
intervening years are discarded. These period wise decomposition results are less
informative and hence may not result in superior representation to the real
situation. Apart from rising incomes and population, these models also account
for fuel mix in primary and final energy consumption as well as structural
effects. The analysis is not only conducted on an aggregate level, but also for the
industry and transport sector.
Energy and the Economy
2. Energy and the Economy
2.1 The Current Energy System
Energy is involved in everything that happens on earth. Vast quantities of energy
sources (fossil, nuclear and thermal energy) are still accessible by either
conventional or enhanced technologies; but the consequences of location,
development and utilization of these energy sources is shaping the global
political and economic landscape and directly affect living standards and
prosperity. Therefore any discussion of employment, technology,
competitiveness and economic growth must consider the strategic role of energy.
In a historical perspective, the human utilization of energy commenced about
half a million years ago with the burning of wood for lighting, heating and
cooking. By the eighteenth and nineteenth century, coal was used instead of
firewood and formed the basis for industrialization through the production of iron
and the invention of the steam engine. These coal-fired steam engines later gave
way to oil and gas supplied systems. Since the 1950s nuclear energy is used in
parts of the world to generate electricity. Figure 2 presents the development of
U.S. energy consumption by source over the last centuries.
Figure 2: History of energy consumption in the United States
Within the current energy system, oil is still the largest primary energy source
consumed globally, followed by coal, natural gas and hydroelectricity. Coal is
the fastest-growing fuel, whereas oil has lost market share in the last years. On a
regional level, oil is the dominant fuel in the Americas, the Middle East and
Africa. Gas is the dominant fuel in Europe and Eurasia and as coal meets 70% of
PetroleumHydroelectricCoalWoodNatural GasNuclear
quadrillion Btu
0
40
35
30
25
20
15
10
5
45
1775 19751950192519001875185018251800 2000Source: Energy Information Administration (EIA).
Energy and the Economy
8
China’s energy needs it is the most important primary energy source in Asia-
Pacific. In 2006 12.7% of Total Primary Energy Supply (TPES) was produced
from Renewables (see Figure 3).
Figure 3: Total primary energy supply by fuel – World 2006
While in high-income countries the majority of renewable energy sources like
wind and solar energy are used to generate electricity, on a global basis a big part
of renewables is used in the residential sector in the form of biomass. On a
global basis solid biomass is by far the largest renewable energy source due to its
extensive non-commercial use in developing countries. Together with other
renewable combustibles and waste it represents 9.9% of world TPES and 78.1%
of renewable supply. With 17.5% and 3.1% of global renewable supply the
second and third largest renewable sources are hydro power and geothermal
energy. More interesting, solar, wind and tidal energy only contribute 1.2% of
renewable supply, which is approximately 0.5% of TPES (see Figure 4).
Figure 4: Renewable energy supply by product – World 2006
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Energy and the Economy
9
Following coal and natural gas, renewables are the third largest contributor to
worldwide electricity production. According to the 2008 edition of the IEA
Renewables Information they accounted for 18.1% of global generation in 2006
(see Figure 5)9.
Figure 5: Global electricity production 2006 – fuel shares
Driven by their use in transport, oil products are the most important final energy
commodity with a global share of 43% in 2006. Electricity accounts for about
17% of total final consumption (see Figure 6) and is still growing.
Figure 6: Total final energy consumption by fuel – World 2006
The main reasons for this rising electricity consumption are the increased use of
electrical appliances (air conditioning, lighting, IT equipment, etc.) and the
advent of new electrical devices in the service sector. In the residential sector,
rising incomes, higher living standards and the trend towards smaller households 9 See IEA (2008c), p.5.
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Energy and the Economy
10
lead to more and larger dwellings and a growing demand for electrical appliances
such as refrigerators, freezers, washing machines, dishwashers, TVs and dryers
as well as a growing number of smaller appliances such as videos and computers.
Around 17% of total final energy consumption is attributed to natural gas. In the
industry sector it is used to produce steel, glass, paper, clothing, brick, and as an
essential raw material for many other products such as paints, fertilizers, plastics,
medicines and explosives. Households use natural gas as a major heating fuel and
to fuel stoves, water heaters, clothes dryers, and other household appliances.
Three sectors are responsible for approximately 80% of global energy
consumption, namely the transport, the industry and the residential sector (see
Figure 7). The transport sector is almost solely relying on oil and is growing fast;
particularly in developing countries (see also Chapter 6 for a detailed description
of the transport sector). The residential sector consumes electricity for all kinds
of appliances as well as gas and oil for heating purposes, whereas industrial
processes use all secondary energy sources (see also Chapter 5 for a detailed
analysis of the industrial sector).
Figure 7: Total final energy consumption by sector– World 2006
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Energy and the Economy
11
2.2 Resources and Reserves of Fossil Fuels: Limits to Growth?
Fossil fuels can be considered as mineral resources that mostly result from burial
and transformation of biomass during the last 200 million years. A resource in
this sense can be defined as “a concentration of naturally occurring solid, liquid
or gaseous material in or on the earth’s crust in such form and amount that
economic extraction of a commodity from the concentration is currently or
potentially feasible”.10 Reserves however refer to material contained in
established and exploitable deposits. At a given time, reserves of a given
commodity include only that part of its resources which is available for
exploitation. Resources of fossil fuels can be categorized by two parameters: (1)
degree of certainty under the present state of knowledge, and (2) feasibility of
economic recovery under the present conditions and available technologies.11
This implies that the amount of reserves depends on current prices of the energy
carrier as well as on technological progress.
Figure 8: Reserves and resources for fossil fuels (excl. Uranium)
Reserves and resources of oil, gas and coal are dynamic quantities as new
technologies are developed and new discoveries are made. The estimation of
potential resources of a commodity is difficult. Due to the uncertainty of price,
market and technological development it is hard to assess what can be considered
as potentially available and recoverable in the future. According to the United
Nations Framework Classification for Fossil Energy and Mineral Resources
10 See Brown (2002), p. 25. 11 See Brown (2002), p. 25.
Source: BGR (2007), p.35.
Energy and the Economy
12
(UNFC)12, initial resources of an energy commodity can be described in terms of
a) produced quantities (or cumulative production in Figure 8), b) remaining
recoverable quantities and c) additional quantities remaining in-place. Produced
quantities are the sum of sales and non-sales quantities between the time of the
first recorded production and the time of the evaluation. The remaining
recoverable quantities are the sum of (sales and non-sales) quantities estimated to
be produced from the evaluation time onward. Additional quantities are
estimated to be in-place at the time of evaluation but not yet produced or
recoverable. The UNFC categorizes the remaining resources using the following
recoverability criteria:
• Economic and commercial viability
• Field project status and feasibility
• Geological knowledge
These criteria are also implicitly used in the other existing resource
classifications. The fact that the future availability of reserves depends on the
level of energy prices and technological progress has led to a rising figure for
crude oil and natural gas reserves in the last three decades (see Figure 9 and
Figure 10).
Figure 9: Proved oil reserves (1980-2007)
12 See UN (2010), p.16.
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Energy and the Economy
13
Figure 10: Proved gas reserves (1980-2007)
An indicator often used and as often misinterpreted in this context is the
Reserves-to-Production (R/P) ratio. The R/P ratio is expressed in years and
interpreted as the remaining amount of a depleting natural resource, mostly
applied to fossil fuels. These ratios may be calculated for individual countries or
globally for specific resources, the latter being used as an indicator of the time
remaining before the resource is completely exhausted.
Figure 11: Global Reserves-to-Production ratio for oil (1980-2007)
As Figure 11 and Figure 12 exhibit, the R/P ratios for crude oil and natural gas
remained almost stable in the last 25 years despite rising energy demand and
resulting growth in production, which is also due to the increase in proved
reserves (see Figure 9 and Figure 10).
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Energy and the Economy
14
Figure 12: Global Reserves-to-Production ratio for gas (1980-2007)
Today, the global R/P ratio for crude oil is slightly above 40 years, proved
natural gas reserves would be depleted in about 60 years at the current rate of
extraction. According to data of the World Energy Council13 the R/P ratio for
coal was 133 years in 2007, so that coal is the fossil energy carrier with the
longest range.
As fossil fuels are exhaustible resources there have always been discussions
about when the world runs out of these resources and what consequences the
ongoing depletion has on energy prices and energy supply security. The so called
“Peak Oil” theory is the most prominent base for controversial discussions of
experts and politicians. This theory was originally developed in 1956 by the
geophysicist Marion King Hubbert, who used extraction and depletion rates of
oil in order to determine the peak of global oil production.14 The advocates of
this theory argue that despite growing statistical reserves the gap between annual
global consumption and new global discoveries has widened within the same
time period. Others argue that there is no physical problem, rather an investment
problem on the transition path from oil – mainly needed for transport – to
alternative fuels.15 As mentioned before, the future availability of fossil energy
resources is a function of their prices and technological progress. This is
expressed graphically by Figure 13 which shows the various oil prices at which
the exploitation of different resources becomes an economical option, taken into
13 See WEC (2007). 14 See Hubbert (1956). 15 See Mabro (2006).
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��
(�
��(� ��(� ��(� ��(� ���� ���� ���( ���� ���� ����
-!�� Source: BP (2008); author’s own illustration.
Energy and the Economy
15
account the cost of capture and storage of CO2 produced during the extraction of
non-conventional oils.
For oil the extraction represents the dominant cost, whereas for natural gas the
economics are dominated by the cost of transportation. Future gas supply is
therefore determined by the development of liquefied natural gas and other
transportation technologies. 16
Figure 13: Oil cost curve
A more profound concern is the global allocation of fossil energy resources.
More than 60% of global crude oil reserves are located in the Middle East, 12%
in Europe and Eurasia – mostly within the territory of the Former Soviet Union –
and 9% in Central and South America (here the bulk of oil reserves lies in
Venezuela) as well as Africa. Only small reserves can be found in the top
consuming regions North America, Western Europe, Japan and China (see Figure
14).
16 See IEA (2005), pp.111 ff..
Energy and the Economy
16
Figure 14: Oil reserves 2007 by region
Natural gas reserves are also allocated unevenly. As shown in Figure 15, most of
the reserves lie in the Middle East as well as Europe and Eurasia. Once again it is
the Russian Federation that holds 75% of the gas reserves within this region.
Figure 15: Gas reserves 2007 by region
Europe’s and North America’s dependency on imported energies will increase
even further in the future, as domestic reserves will be depleted first. This has a
major geopolitical impact, as the political and economic power of the oil and gas
exporting countries will continue to rise. An uninterrupted flow of energy
depends on the political and economic stability of the producer regions. At least
for the Middle East this stability is questionable and Russia is already using its
position strategically in foreign relations. Many oil producing countries have
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3 ����� �5� ��
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Source: IEA online database; author’s own illustration.
Source: IEA online database; author’s own illustration.
Energy and the Economy
17
experienced the so called “Dutch disease”, i.e. negative effects of producing a
singular product for the world market and an uneven internal distribution of oil
revenues can lead to political instability17. However, growing energy import
dependency also leads to sharper competition among consumer countries. As
global demand for energy continues to rise, the major players like the United
States, European Union, Japan and China are facing a race to secure long-term
energy supplies. Due to its booming economy, China is intent on getting the
resources needed to sustain its rapid growth and has already turned to Africa as a
major source for oil often overlooked by the Europeans and Americans.
Consequently Chinese energy companies are committing large amounts of
funding and labour for exploration and development rights in resource-rich
countries.
Figure 16: Coal reserves 2007 by region
Figure 16 shows the regional distribution of coal reserves. Due to its large
reserves and availability within the major energy consuming regions, coal will
remain the dominant fuel for global electricity generation. Amongst the major
energy sources, coal is the most rapidly growing fuel as it is abundant and
broadly distributed around the world. Economically recoverable reserves of coal
are available in each major world region.18 The high specific carbon dioxide
content however makes it problematic on ecological grounds.
17 See CIEP (2004), p.19. 18 See WEC (2007), p. 1.
����.�3�!�� ����
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��
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8�''�!�� ��6�35�� ���
3 ����� �5� ���
Source: IEA online database; author’s own illustration.
Energy and the Economy
18
The role of nuclear power for electricity generation depends on the availability of
uranium. The biggest “Reasonably Assured Resources” (RAR) can be found in
Australia, Canada, Kazakhstan, Niger and Brazil. These countries account for
over 80% of global uranium resources19. As global electricity consumption is
expected to continue growing over the next several decades to meet the needs of
an increasing population and further economic growth, nuclear energy will
continue to play an important role in generating the required electricity, although
the magnitude of that role remains uncertain. This is mostly depended on the
political debate about advantages and risks of nuclear energy. Some argue that
the use of nuclear power in electricity generation reduces carbon emissions and
increases energy security by decreasing dependence on oil and gas imports.
Opponents point to the problems associated with processing, transport and
storage of radioactive nuclear waste, or the risk of nuclear accidents.
In summary it can be said that the world will not run out of fossil fuels within the
next decades taking technological progress into account. Fossil fuels thus will
continue to dominate energy supply in the future. Nevertheless the geographic
distribution of resources spurs concerns about supply security, and energy prices
will probably not fall back to the level of the 1990s again. Renewable energy
sources – which until now played a minor role in the energy mix – can help to
level out supply disruptions and to reduce the dependency on energy imports
from the Middle East and Russia.
2.3 Growth and the Environment: The Environmental Kuznets Curve
The environmental Kuznets curve (EKC) hypothesis asserts that pollution
follows an inverted-U path with respect to economic growth, i.e. pollution
increases (environmental quality declines) with economic growth up to a certain
income level, after which it declines (improvement of environmental quality).
This hypothesis is adapted from Kunznets’ (1955) original study on the
influences of economic development on income inequality.20 Equally the 1992
World Development Report (IBRD, 1992) argued: “The view that greater
economic activity inevitably hurts the environment is based on static assumptions
19 See OECD (2006b), p.13ff.. 20 See Cavigilia-Harris et al (2009).
Energy and the Economy
19
about technology, tastes and environmental investments” and also that “as
incomes rise, the demand for improvements in environmental quality will
increase, as will the resources available for investment”.21
Pure growth in the scale of an economy would result in a proportional growth in
pollution and other environmental impacts if there were no changes in the
structure or technology of this economy. The view that economic development
and environmental quality are conflicting goals reflects this scale effect alone.22
An inverted-U shape for environmental quality can thus be explained by several
structural factors. One of the arguments is, that production and consumption
change with income. If the industry structure changes from relatively clean
agricultural economies to polluting industrial economies and then to a bigger
share of information-based industries and services, an inverted-U path for the
relationship between economic growth and environmental quality is plausible
due to the changing output mix. If we look at CO2 emissions, increasing income
also leads to changes in the fuel mix, e.g. from coal to natural gas. Another
reason for this relationship could be that environmental awareness tends to grow
with income, i.e. there is positive income elasticity for environmental quality.
This increased demand for environmental quality then forces an active
environmental policy and the creation of institutions to internalize negative
effects caused by pollution. Technological progress can also explain the
appearance of an EKC, e.g. in the form of increasing production efficiency or
changes in the production process that are emission specific.
Early empirical research on the EKC was conducted by Grossman and Krueger
(1991), Shafik and Bandyopadhyay (1992) and Selden and Song (1994). The
working paper by Grossman and Krueger (1991) estimated Environmental
Kuznets Curves for SO2, fine smoke and suspended particles as part of a study on
the potential environmental impacts of NAFTA. The regressions involve a cubic
function in levels of GDP per capita and various site-related variables, a time
trend, and a trade intensity variable. The turning points for SO2 and fine smoke
are at around USD 4,000 to 5,000 while the concentration of suspended particles
appeared to decline even at low income levels. The results of the paper of Shafik
and Bandyopadhyay (1992) were used in the 1992 World Development Report 21 See IBRD (1992), p.38. 22 See Stern (2003), p. 4.
Energy and the Economy
20
cited above. They estimated EKCs by using three different functional forms (log-
linear, log-quadratic and a logarithmic cubic polynomial in PPP GDP per capita
as well as a time trend and site related variables) for ten different indicators (lack
of clean water, lack of urban sanitation, ambient levels of suspended particulate
matter, ambient sulfur oxides, change in forest area, annual observations of
deforestation, dissolved oxygen in rivers, fecal coliform in rivers, municipal
waste per capita, and carbon emissions per capita). Only the two air pollutants
conform to the EKC hypothesis. The turning points for both were found for
income levels of between USD 3,000 and 4,000. Selden and Song (1994)
estimated EKCs for SO2, NOx, SPM, and CO emissions primarily from
developed countries. The estimated turning points are very high compared to the
studies by Grossman and Krueger (1991) and Shafik and Bandyopadhyay (1992),
varying from USD 7,114 for CO to 13,383 for NOx. According to their analysis
the turning point for emissions is likely to be higher than that for ambient
concentrations. Following these initial papers several studies have been focusing
on air pollution, water pollution, deforestation, hazardous waste and toxins,
carbon dioxide and other pollution indicators.23
Looking at the results of these studies it becomes clear that the EKC only holds
for some of the measures of environmental quality and that there is no simple and
predictable relationship between economic growth and pollution. The results do
not only vary depending on the pollutant measurement chosen (e.g. emissions or
ambient concentrations), but also the choice of countries observed, trade effects,
functional form and methodology.
Amongst others Arrow et al. (1995) criticize that most EKC models assume there
is no feedback from environmental damage to economic activity as income is
assumed to be an exogenous variable, i.e. there is an assumption that the
economy is sustainable. The levels per unit of output in specific processes have
declined for many pollutants in developed countries over time due to strict
environmental regulations and technical innovations. Nevertheless for other
pollutants this relation is still rising, as the mix of waste changes over time so
that in sum per capita waste may not have declined. Economic activity is
inevitably environmentally disruptive in some way (simultaneity). Arrow et al.
(1995) admit that while some empirical findings “indicate that economic growth
23 See for example Huang et al. (2008), p. 240 f. for an extensive literature review.
Energy and the Economy
21
may be associated with improvements in some environmental indicators, they
imply neither that economic growth is sufficient to induce environmental
improvement in general, nor that the environmental effects of growth may be
ignored, nor, indeed, that the Earth's resource base is capable of supporting
indefinite economic growth”.24
If an EKC type relationship is found it might also be a result of the effects of
trade on the distribution of polluting industries. Trade theory suggests that, under
free trade, developing countries specialize in the production of goods that are
intensive in the more abundant factors labour and natural resources. The
developed countries in turn specialize in human capital and manufactured capital
intensive activities. This specialization leads to reduction in environmental
degradation levels in developed countries and an increase in environmental
degradation in middle and low income countries. This effect is even aggravated
by higher environmental regulation standards in developed countries. So even if
an EKC exists locally, global pollution may increase, since the fastest economic
growth occurs in developing countries with the highest population growth.
Lucas et al. (1992) found evidence that stricter environmental regulation in
OECD countries has led to a relocation of polluting industries towards poorer
developing countries. According to Dasgupta et al. (2002) some critics even
argue that globalization promotes a “race to the bottom”, i.e. the curve will rise to
a horizontal line at maximum pollution levels. This is the case when
industrialized countries relax their environmental standards in order to win back
capital outflows to low-income countries. But it remains to be proven that
developed countries are really reducing their environmental standards. Others
argue that even if some pollutants are reduced with rising incomes our economies
continuously create new and unregulated pollutants. According to Dasgupta et al.
(2002) “such concerns raise the possibility that economic development will
always be accompanied by environmental risks that are either newly discovered
or generated by the use of new materials and technologies”.25
The environmental Kuznets curve therefore implies that less developed countries
– also represented by large and fast growing economies like China and India –
will experience increasing pollution levels until a large rise in per capita income
24 See Arrow et al. (1995), p. 520. 25 Dasgupta et al. (2002), p. 162.
Energy and the Economy
22
has been achieved. Nevertheless the goal of environmental regulation must be a
shift to the left and flattening of the EKC (“Revised EKC” in Figure 17).
Figure 17: Alternative views on the Environmental Kuznets Curve
The results from numerous empirical papers on the EKC show that there is little
evidence for a common inverted U-shaped pathway which countries follow with
rising income. It is therefore questionable whether the EKC is a complete model
of emissions. Stern (2003) explicitly points to the importance of decomposition
analysis to study the impact of economic growth on pollutants, especially carbon
dioxide emissions. “The research challenge now is to revisit some of the issues
addressed earlier in the EKC literature using the new decomposition models and
rigorous panel data and time series statistics”.26
In the following chapters advanced time series and decomposition methods will
be used to analyse whether economic growth inevitably increases pollution,
taking into account energy efficiency improvements, changes in the energy mix
and structural effects.
26 See Stern (2003), p. 20.
New Toxics
Race to the Bottom
The EKC
Revised EKC
Economic Growth (GDP per capita)
Pollution
Source: Dasgupta et al. (2002).
The Relationship between Energy Prices, Energy Consumption and Growth
3. The Relationship between Energy Prices, Energy Consumption and
Growth
3.1 Granger Causality
One possibility to investigate the relationship between energy consumption and
GDP is the use of Granger causality tests in time series analysis. The directions
and policy implications for the causal relationship between energy consumption
and economic growth can be categorized as follows. If it is found that
unidirectional causality runs from energy consumption to economic growth, then
restrictions on the use of energy could lead to a reduction in GDP growth. Many
countries worry about this negative effect on income caused by the restricted use
of energy, as the pressure to mitigate CO2 emissions in order to slow down the
rate of climate change grows. On the other hand, if unidirectional causality runs
from GDP to energy consumption, then energy conservation measures may be
implemented with little or no adverse impacts on growth. A bi-directional causal
relationship implies that energy use and economic growth are jointly determined
and affected at the same time. If no causal relationship between the two variables
is found, then the “neutrality hypothesis” holds. Adding energy prices as a third
variable allows for an additional channel of causality and helps to investigate
whether energy prices have a significant impact on energy consumption or even a
direct effect on GDP growth.
In recent years there has been a revival of literature on the causal relationship
between energy use and economic growth. This is not only due to the fact that
supply security, climate change and rising energy prices have been on the
political agenda once again. Apart from that, there are also new developments in
econometrics, most of all the use of panel cointegration techniques that make it
possible to solve the problem of small samples which is still prominent in the
energy literature, as there is only limited availability of time-series for energy
use. In general the causality literature differs in the methodology applied, the
variables analyzed, the countries or regions studied and the time period observed
(see overview in Table 1).
The Relationship between Energy Prices, Energy Consumption and Growth
24
Stu
dy
Me
tho
dC
ou
ntr
ies
Pe
rio
db
ivar
iate
de
man
dsu
pp
lye
->y
y->
e-
1A
kinl
o (2
008)
Aut
oreg
ress
ive
Dis
trib
uted
Lag
(A
RD
L)11
Sub
-Sah
ara
Afr
ican
cou
ntrie
s19
80-2
003
1�
��
2A
l-Iria
ni (
2006
)P
anel
Coi
nte g
ratio
n an
d V
ecto
r E
rror
Cor
rect
ion
6 G
CC
cou
ntrie
s19
71-2
002
1�
3A
ltina
y an
d K
arag
ol (
2004
)G
rang
er c
ausa
lity,
Hsi
aoT
UR
1950
-200
01
X4
Asa
fu-A
djay
e (2
000)
Coi
nteg
ratio
n an
d V
ecto
r E
rror
Cor
rect
ion
IND
, ID
N, T
HA
, PH
L19
71/7
3-19
951
�
5C
hen,
Kuo
and
Che
n (2
007)
Pan
el C
oint
egra
tion
and
Vec
tor
Err
or C
orre
ctio
n10
asi
an c
ount
ries
1971
-200
11
��
6C
hen g
and
Lai
(19
97)
Coi
nteg
ratio
n an
d V
ecto
r E
rror
Cor
rect
ion
TW
N19
55-1
993
1�
7C
hont
anaw
at e
t al (
2006
)G
ran g
er c
ausa
lity,
Hsi
ao, E
CM
> 1
00 c
ount
ries
1960
-200
0 (O
EC
D);
1
XX
X8
Cho
ntan
awat
et a
l (20
08)
Gra
nger
cau
salit
y, H
siao
, EC
M>
100
cou
ntrie
s19
60-2
000
(OE
CD
);
1X
XX
9D
inda
and
Coo
ndoo
(20
06)
Pan
el C
oint
egra
tion
and
Vec
tor
Err
or C
orre
ctio
n88
cou
ntrie
s gr
oupe
d in
to 1
2 r
egio
ns19
60-1
990
1X
X10
Ero
l and
Yu
(198
7)S
ims
& G
rang
erU
SA
1973
-198
41
�
11F
atai
et a
l (20
04)
Coi
nte g
ratio
n an
d V
ecto
r E
rror
Cor
rect
ion
(Eng
le G
rang
er,
NZL
, AU
S, I
ND
, ID
N, P
HL,
TH
A19
60-1
999
1X
X12
Gho
sh (
2002
)C
oint
egra
tion
and
Vec
tor
Err
or C
orre
ctio
nIN
D19
50-1
997
1X
13G
lasu
re a
nd L
ee (
1997
)C
oint
egra
tion
and
Vec
tor
Err
or C
orre
ctio
nK
OR
, SG
P19
61-1
990
1�
�
14H
ondr
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l (20
02)
Coi
nteg
ratio
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rror
Cor
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GR
C19
60-1
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1X
X15
Hu
and
Lin
(200
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hres
hold
Coi
nteg
ratio
n an
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rror
Cor
rect
ion
TW
N19
82-2
006
(qua
terly
) 1
XX
16Ji
nke
et a
l (20
08)
Coi
nteg
ratio
n an
d V
ecto
r E
rror
Cor
rect
ion
US
A, J
PN
, KO
R, C
HN
, IN
D, Z
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1980
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51
XX
17Ju
mbe
(20
04)
Coi
nteg
ratio
n an
d V
ecto
r E
rror
Cor
rect
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MW
I19
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999
1X
X18
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8)S
ims
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rang
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-197
41
�
19Le
e (2
005)
Pan
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tion
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tor
Err
or C
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trie
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20Le
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y, T
oda-
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1960
-200
1 (D
EU
: 197
1-20
01; C
AN
: 196
5-20
01)
1X
XX
21Le
e an
d C
hang
(20
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Pan
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tor
Err
or C
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dev
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ntrie
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21
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21
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23Le
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OE
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Mah
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20 e
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port
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and
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s19
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)C
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tor
Err
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nIN
D, P
AK
, MY
S, S
GP
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-199
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1991
, 19
60-1
990
1X
XX
27M
asih
and
Mas
ih (
1997
)C
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tion
and
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tor
Err
or C
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, TW
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11 o
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29M
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rror
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ion
BG
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1X
30N
acha
ne e
t al (
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)C
oint
egra
tion
and
Vec
tor
Err
or C
orre
ctio
n16
cou
ntrie
s (1
1 LD
Cs,
5 D
Cs)
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-198
51
��
X
31N
aray
an a
nd P
rasa
d (2
008)
boot
stra
pped
Gra
nger
cau
salit
y te
st30
OE
CD
cou
ntrie
s19
60-2
002,
196
5-20
02,
1970
-200
2, 1
971-
2002
1X
XX
32N
aray
an a
nd S
myt
h (2
008)
Pan
el C
oint
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tion
and
Vec
tor
Err
or C
orre
ctio
nG
719
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002
1X
33O
h an
d Le
e (2
004)
Coi
nteg
ratio
n an
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rror
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rect
ion
KO
R19
70-1
999
1�
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34S
ari e
t al (
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)A
RD
LU
SA
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:1-2
005:
6 (m
)1
XX
35S
hiu
and
Lam
(20
04)
Coi
nteg
ratio
n an
d V
ecto
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rror
Cor
rect
ion
CH
N19
71-2
000
1X
36S
oyta
s an
d S
ari (
2003
)C
oint
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tion
and
Vec
tor
Err
or C
orre
ctio
nG
7 an
d to
p 10
em
ergi
ng c
ount
ries
(exc
l. C
HN
)
1950
-199
2 (A
RG
: 195
0-19
90; I
DN
: 196
0-19
92;
KO
R: 1
953-
1991
; PO
L:
1965
-199
4)1
XX
X
37S
tern
(19
93)
VA
R a
nd G
rang
er c
ausa
lity
US
A19
47-1
990
1X
X
38S
tern
(20
00)
Coi
nteg
ratio
n an
d V
ecto
r E
rror
Cor
rect
ion
US
A19
48-1
994
1X
39Y
ang
(200
0)C
oint
egra
tion
and
Vec
tor
Err
or C
orre
ctio
nT
WN
1954
-199
71
��
40Y
u an
d H
wan
g (1
984)
Sim
s &
Gra
nger
US
A19
47-1
979
1�
41Za
char
iadi
s (2
007)
3 m
odel
s: V
EC
, AR
DL,
Tod
a-Y
amam
oto
G-7
1960
-200
41
XX
X
42Zo
u an
d C
hau
(200
6)C
oint
egra
tion
and
Gra
nger
cau
salit
yC
HN
1953
-200
21
X(X
)
mu
ltiv
aria
teD
ire
ctio
n o
f ca
usa
lity
Table 1: Literature review
Source: author’s own illustration.