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Sustainable globalization and energy Simone Borghesi (University of Siena, Dept. of Political Economy; University of Pescara, Dept. of Quantitative Methods and Economic Theory) Alessandro Vercelli (University of Siena, Dept. of Political Economy) Daniele Verdesca (University of Siena, Dept. of Political Economy) February 2005 Preliminary version Abstract This paper discusses whether and to what extent the recent developments in energy consumption are compatible with the requirements of sustainable globalization. For this purpose, we first critically discuss the conventional position on the market capacity to resolve spontaneously the problems of energy scarcity and pollution, pointing out some important shortcomings that may affect this optimistic approach. Then, using a simple identity applied to the energy sector, we derive the condition for long-term energy sustainability and examine whether and where such condition is satisfied on the basis of the currently available data. Address for correspondence: Simone Borghesi D.M.Q.T.E. (Dipartimento Metodi Quantitativi e Teoria Economica) Facoltà di Scienze Manageriali Università di Pescara Viale Pindaro, 42; I-65127 Pescara, Italia e-mail: [email protected]; tel: (+39) 339-4448220 JEL Classification: F02, O13, Q32, Q42, Q43 Keywords: globalization, sustainable development, energy, environment, environmental Kuznets curve. 1. Introduction In this paper, we will discuss the extent to which recent developments in energy consumption are compatible with the requirements of sustainable globalization. The current pattern of energy production, distribution and consumption is very vulnerable. This is because it is based almost exclusively on the use of fossil fuels (coal, natural gas and, above all, oil) whose reserves are strictly limited, although public opinion is divided on the nature and the size of these limits. There is however unanimous agreement on the fact that the age of fossil fuels is bound to decline during this century, progressively giving way to renewable energy sources such as wind power and photovoltaic energy, hydrogen, and, according to someone, nuclear energy. Nevertheless, opinion is divided on what the characteristics of the new model should be, as regards the timing and the ways of making changes and therefore as regards also the best economic, energy and environmental policies to guide and set the pace for the transition process. Today’s energy model is vulnerable not only because fossil fuels are scarce, but also because their reserves are remarkably concentrated in terms of location and ownership. This exposes energy production and distribution to considerable geopolitical dangers which clearly emerged in the 1970s when the two oil shocks of 1973 and 1979 provoked a serious crisis in the world economy due to cost inflation and, at the same time, increased unemployment caused by economic stagnation (stagflation). Furthermore, the territorial concentration of the reserves favored the consolidation of centralized and hierarchical energy infrastructures (Rifkin, 2002, p.9) which accentuated the vulnerability of the energy model. World energy supplies depend on a network of oil and gas pipelines and petrol tankers – a network which has its head and “pumping heart” in the Middle East. Any problem occurring at the heart of the fossil fuel circulatory system which animates the “body” of the world economy, would have devastating repercussions for the entire circulation of the lymph of vital energy. This has contributed to the dangerous conflicts for economic and political leadership over the area of the Middle East with serious consequences for this “circulation of energy”, consequences which could be even more serious in the future. Lastly, the very high costs linked to prospecting, extracting, refining and distributing oil and other fossil fuels require colossal investments which only mega-enterprises can manage. This has created an oligopolistic market dominated by eight multinational energy giants on whose strategies depend the world energy supply and the oil price which in turn strongly conditions the performance of the world economy. For all these reasons, the current energy model is extremely vulnerable and risks endangering not only the sustainability of development but also the progress of world economic development. In this paper we will limit ourselves to considering whether the transition process under way is compatible with sustainable development. This analysis will provide some useful indications on the optimum characteristics that the energy model should have and on the most opportune policies to make the transition process consistent with the sustainability requirements. For this reason, after having illustrated the conventional position on energy production and consumption (section 2), we will examine it more carefully from a critical viewpoint (section 3). The analysis of the available data and the resulting projections for the future raises questions about the compatibility of current trends with sustainable development (section 4). The conclusions, summarized in section 5, stress the need for a new decentralized model of energy production and consumption based on energy-saving and on the systematic use of renewable energy sources combined with the use of hydrogen. 2. The conventional position First of all, we will briefly summarize and then make a critical examination of the dominant position held today concerning the production and consumption of energy sources – a position held by the main energy producers and most government energy agencies, even if with different nuances. For ease of reference, we will call this the “conventional position”, widely disseminated and publicized by the mass media. The “conventional position” is characterized by a marked optimism about the capacity of the market and market-oriented technical progress to resolve any energy problems quickly. The basic premise of this position is the conviction that the sure economic scarcity of energy sources does not depend on an unavoidable physical scarcity, not even as regards fossil fuel which represents the pillar of today’s energy production and consumption model. This position is often corroborated by tables and figures illustrating the paradox whereby known usable reserves and proven reserves of single sources of fossil fuels, including oil, are supposed to have gradually increased in the last few decades (see figs. 1 and 2).1 This can help to explain why, over the years, T, representing expected lifespan, has been upwardly revised for many depletable resources, including fossil fuels (table 5), in this way contradicting the initial forecasts of the Rome Club (Meadows et al., 1972) according to which, for example, oil supplies would already have run out by the early 1990s. Fossil fuels T1970 (Source: Meadows et al., 1972) T1994 (Source: British Petroleum 1995) T2002 (Source: British Petroleum 2003) Coal Natural gas Oil 111 22 20 139 42 35 204 60.7 40.6 Table 5: expected lifespan of fossil fuel reserves measured in number of years (T) starting from different base years (1970, 1994 and 2002)2 The paradox of an increase over time of these depletable resources is normally explained in terms of technical progress whereby more and more reserves are found as a result of increasingly sophisticated methods of prospecting. Furthermore, technical progress should allow the exploitation - at competitive prices - of reserves that are increasingly difficult to use, for reasons of location (e.g. under the sea), depth, and quality of the raw material. The observed increase over time of fossil fuels reserves and the underlying explanation have generated the widespread conviction that the age of fossil fuels will not exhaust its leading role for another few decades, that the transition towards an alternative energy model could be just as gradual and that it could be managed by the “spontaneous” forces of the market and technical progress. Sheikh Yamani, the powerful OPEC leader, used to say that the Stone Age did not come to an end because there were no more stones and the Age of Oil would not come to an end because there was no more oil. From this standpoint, the transition will come about spontaneously when the cost of one kWh produced from fossil fuels exceeds the cost of 1 Using the terminology adopted by British Petroleum (2003), the term “proven reserves” indicates those quantities that, on the basis of the geological and engineering information available, can be recuperated in the future with reasonable certainty from the known reserves under existing economic and operating conditions. 2 The expected lifespan T is calculated by British Petroleum as the relationship between the remaining proven reserves at year end and that year’s output, assuming that output will continue at the same level in the future. one kWh produced by renewable energy.3 This transition towards an alternative technology (the so-called “backstop technology”) should not happen much before 2050. The conventional position described before does not obviously deny the economic scarcity of fossil fuels, which generates from time to time a tendency for demand to exceed supply. However, the dominant viewpoint is that these situations are to be interpreted as essentially episodic instances (such as during the widespread blackouts of recent years). These instances can be defined as “cyclical” when demand exceeds planned supply following a cyclical boom in national income, or as “extra-economic” in cases such as the two oil shocks of the 1970s. It is therefore a case of a temporary, local or sectoral scarcity which will in any case be limited in time and space; a scarcity to which the market will respond spontaneously with the consequent increase in the price of the scarce fuel. From this standpoint, the increase in price of the scarce fuel stimulates technological progress to find alternative solutions that allow lower consumption. Such stimulation will be stronger, the more chronic the economic scarcity of a particular energy source becomes. An increase in the fuel price also shifts the demand towards suppliers or reserves which, following such a price increase, become economically worthwhile. So, for example, the rapid increase in the price of oil provoked by the two shocks in the 1970s, made it worthwhile to extract oil in other geographical areas, such as the North Sea, the USA, Russia and Mexico, where average production costs were considerably higher than in the OPEC countries.4 This determined a reduction over time in OPEC’s share of world oil production which led the member countries to reduce the price they had established in order to gain back the share they had lost.5 3 Since fossil fuels are by nature depletable resources the correspondent cost is bound to rise in the long term. 4 It has been estimated, for example, that the average production cost in the Arab countries is between 1 and 2 dollars a barrel, while in the North Sea it ranges between 7 and 10 dollars a barrel. 5 In a similar way, the observation that the productive capacity of the North Sea could have reached its upper limit led OPEC to cut its own production by about 1.7 million barrels a day in the period 1999-2000. Together with the embargo on Iraq, this increased the price from 15 to over 34 dollars a barrel. The relationship between the OPEC cartel and the non-OPEC countries (the so-called “cartel-fringe” relationship) is at the centre of numerous theoretical models analyzing variations over time in OPEC’s production decisions in relation to those of its competitors and the consequent changes in the leadership of the productive market (cf. for example Ulph and Folie, 1980; Geroski et al., 1987). Also as regards pollution, the conventional position maintained a rather optimistic attitude in the 1990s, one which it still holds today. On the basis of a reduction in energy intensity observed in those years (fig. 3) and in the carbon content per unit of consumption (fig. 4), the conviction grew that the pollution generated by energy consumption had started to stabilize. In this spirit, some even applied the Environmental Kuznets Curve to energy consumption, drawing the hurried conclusion that in order to resolve the environmental problems raised by energy consumption, it would suffice to promote economic growth.6 For example, figure 5 suggests that, in all countries, energy intensity increases first of all when the industrialization process gets under way, due to the development of heavy industry and higher consumption linked to urbanization; later it falls following the development of light industry and services and as a result of the pressure of public opinion and the electorate who have become more aware of environmental quality issues. The conventional position is basically the dominant one in all the industrialized countries but opinion is divided on the best environment and energy policy to make the transition to a new model of energy consumption as painless as possible. In some countries, among which many European ones, it is thought that command and control instruments and environment taxation are inevitable in order to accelerate the transition to a new model of energy consumption, while in other countries, and notably in the USA, it is considered preferable to negotiate permits and voluntary agreements between enterprises and the environment and energy authorities to reduce the pollution and the wasting of resources that characterize the current energy model. 3. Limits to the conventional position The conventional position is reassuring but not very convincing. Above all, it risks underestimating the physical scarcity of fossil fuels. The latest data at our disposal do not support the paradox of their growing availability. For example, as regards oil, its estimated availability seems to have reached its peak in the mid-1990s after which it began to fall. Moreover, there are many indications that the above-mentioned paradox 6 Various empirical studies have recently analyzed the hypothesis of the Environmental Kuznets Curve in the case of energy. Amongst these, Cole et al. (1997), Suri and Chapman (1998), Sun (1999), Galeotti and Lanza (1999), and Focacci (2003). See also Cleveland et al. (2000) and Soytas and Sari (2003) for an analysis of the causality links was furthered by “creative” economic-geological accounting based on estimates, for the most part discretionary, which were rather over-optimistic. Of course, the proponents of these estimates may have an interest in inflating them. The producer countries do so in order to obtain higher production quotas and better conditions for the large loans they contract with the banks and international organizations. In the same way, the oil multinationals who participate in the datagathering process and in the estimates of the residual reserves, have an interest in overestimating the reserves under their control in order to improve the performance of their shares on the stock exchange and to increase their political and financial bargaining power. In any case, leaving aside any skirmishes regarding the data on residual reserves, there is general agreement on the fact that the age of fossil fuel must come to an end before very long. However, opinion is quite strongly divided on the energy production and consumption model to adopt and also on when and how to change over to the new model. The speed and the nature of the transition depends crucially on the evolution of the cost of production per kWh for the single energy sources (fig. 6). All agree that in the new energy model, the sources of renewable energy must have a predominant role. As we have seen, according to the conventional position, this cannot happen before 2050. Nevertheless, this assessment, which is crucial for steering energy choices from now on, is not only a question of fairly accurate forecasting but is also, and above all, a question of energy and environment policy. If the large state subsidies granted to the production and distribution of energy from fossil fuel were abolished, this could considerably accelerate the transition to the use of renewable energy sources. Further acceleration could be achieved by channeling the above-mentioned subsidies to the renewable energies sector to encourage the immediate utilization of the potential economies of scale which would considerably hasten the process. If these measures, like those favoring fossil fuels, were considered distortive, it would still be possible to divert towards the renewable energies sector those subsidies and incentives for technical progress which today go almost exclusively to the fossil fuel sector. Nevertheless, there are some very powerful economic, financial and political interests that are trying to slow down the transition. All states and enterprises with big interests in the fossil fuel sector would like to exploit the economic opportunities it offers for as long as possible. between energy consumption and income growth, and Borghesi (2001) for a general survey of the literature on the environmental Kuznets curve. Paradoxically, the physical scarcity of fossil fuel sources means that all those who have an interest in the sector are trying to make maximum profits from their use before they run out or before they become too costly to exploit and, in any case, before the already fragile political stability of the producer countries comes to an end.7 If we interpret the available resources as a relatively illiquid financial asset, it seems clear that an owner will try to liquidate this asset as rapidly as possible before its value is undermined by the lower price per kWh of renewable energy. Alternatively, to maintain their own position in the energy market, the owners of fossil energy sources could try and invest in backstop technology, getting ahead of any other competitors in research terms, so as to keep on meeting the demand for energy when the price of fossil fuel exceeds that of renewable resources. This could help to explain why some large oil companies (e.g. Shell) have, in recent years, invested in renewable energy sources such as, for example, solar energy. Furthermore, even the States who import most of the available fossil fuels are reluctant to take direct steps to reduce their consumption because of the sizeable tax revenues they earn from fossil fuel consumption. As to the market optimism characterizing the conventional position, it could be claimed that in the energy field the myth of the invisible hand in the competitive market is particularly groundless. The allocation of resources and the prices for their use are moved by hands that are both visible and easy to identify: multinational oil companies, OPEC, and the energy policies of the great powers. 4 The transition in course and sustainable development Current trends seem to be incompatible with sustainable development. To explain this point, let us now apply to the energy sector the well-known IPAT identity originally proposed by Holdren and Ehrlich (1974). That identity was recently reformulated by Borghesi and Vercelli (2003) to examine whether the globalization process can be considered sustainable and can be applied to the energy sector in the following way: 7 In this regard, Boyce (1994) advances the hypothesis that in countries with high levels of inequality (such as the oil-producing countries) the richest individuals and enterprises tend to apply a higher discount rate because of the risk of political instability generated by this inequality. For this reason, they would prefer to exploit their own resources as fast as possible in order to invest the resulting profits abroad where political instability and the consequent investment risks are lower. (1) E* = y* + P* + e* where E* is the rate of growth of global demand for primary energy, P* is the rate of growth of the population, y = Y/P is per capita income and y* is its rate of growth, e = E/Y is energy intensity and e* is its rate of growth. The following modified identity derives from (1): (2) D* = y* + P* + e* + d* where d = D/E represents the intensity of energy degradation (i.e. energy degradation D per unit of energy consumption E), d* is the rate of growth of the intensity of energy degradation and D* is the rate of growth of energy degradation. The latter variable is measured, as a first approximation, with the rate of growth of CO2 emissions in that they are considered to be the main cause of the greenhouse effect among the gases produced by fossil fuels (IPCC, 2001) and a reference parameter for the aggregation of the other greenhouse gases (often measured in terms of tons of CO2 emissions equivalent). Furthermore, given that emissions of carbon dioxide specifically characterize the use of fossil fuels, their measurement can be considered as a proxy, even if only a rough one, for the increasing scarcity of these fuels. To ensure the sustainability of the planet, global energy degradation should not increase with time but be reduced or at least remain constant. If it increases, we will move further away from sustainability, while if it decreases, we will move closer towards it. Global energy degradation tends to increase, other things being equal, with an increase in per capita income, unless the sum of the rates of growth of the population (P*), energy intensity (e*) and energy degradation intensity (d*) is negative and greater in absolute terms than the growth rate of per capita income (y*). Therefore, to reduce global energy degradation (and thus achieve sustainability) it is not sufficient that energy intensity follow an Environmental Kuznets Curve as some representatives of the conventional position have suggested (see section 2 above). This can only ensure that e* (but not D*) would eventually become negative. Environmental degradation in the energy sector also depends on the trends of income, population and polluting emissions intensity, as explained by identity (2). Therefore, the condition for long-term energy sustainability is as follows: (3) y* ≤ - (e*+ P* + d*) which can also be expressed in the following way: (4) Y* ≤ -(e* + d*) On the basis of these identities, it is possible to analyze what has happened in the world over the last 30 years (divided into three decades) and the IEA forecasts for the next 30 years (IEA, 2002). The basic data are summarized in table 6. World 1971-1980 Y* 4,1 P* 1,9 y* 2,2 E* 3,0 e* -1,1 D* 2,8 d* -0,2 1981-1990 3,2 1,9 1,3 2,1 -1,1 1,6 -0,5 1991-2000 3,4 1,6 1,8 1,6 -1,8 1,4 -0,2 1971-2000 3,3 1,7 1,6 2,1 -1,2 1,8 -0,3 2000-2030 3,0 1,0 2,0 1,7 -1,3 1,8 0,1 Table 6: IEA scenario. Source: Borghesi-Vercelli-Verdesca (2004) According to the IEA’s forecasts, global energy demand is destined to increase until 2030 at an average rate of 1.7%, while in the same period, fossil fuels will increase their share of demand and international trade. Global energy intensity is destined to fall by 1.3% as a result of technical progress but this is not enough to reduce CO2 emissions which will increase on average by 1.8%, partly because in the meantime the intensity of polluting emissions will have increased, even if only at a very low rate – 0.1% (IEA, 2002) (figs. 7 and 8). The minimum requirement to stabilize pollution seems, therefore, to have been clearly denied. Even the social requirement of sustainability seems to have been strongly denied. The IEA forecasts say that in 2030 there will still be 1.4 billion people without electricity the effects of which will progressively feed into the vicious circle of poverty and inequality. Furthermore 2/5 of energy consumption will still be based on traditional biomass which is a particularly inefficient and polluting source of energy. Lastly, inequality in terms of per capita energy distribution will also remain very marked which will strongly influence access to economic opportunities on the part of the most disadvantaged populations, further increasing inequality and poverty. These pessimistic forecasts, which are based on the today’s economic, energy and environmental policies, are worsened by comparisons with the trends in the key variables over the last three decades. Indeed, the trend in energy consumption has been incompatible with sustainable development over the last thirty years and will continue to be so for the next thirty. Nevertheless, as can be seen clearly in table 6, the situation has been gradually improving over the last three decades of the 20th century, while it seems destined to worsen over the next three. In particular, energy intensity e has fallen more and more rapidly from 1.1% in the 1970s and 1980s to 1.7% in the 1990s. This is the result of greater attention being paid to energy-saving following the oil shocks of the 1970s which was then consolidated by increasingly rigorous energy policies in the ‘80s and ‘90s. Above all in the 1990s, a significant contribution to this virtuous trend was provided by the systematic introduction of information and communication technologies (see Vercelli, 2002). There are however some signs of an inversion of this virtuous trend, linked to a lower tendency towards energy-saving on the part of the industrialized countries’ energy policies and to the more rapid growth of the developing economies such as India and China. These economies are generally characterized by a high energy intensity which brings them high rates of growth of polluting emissions as their GDP grows. Table 7 and the related histogram (fig. 9) show the rate of growth of CO2 emissions in the period 1980-1997 at the world level and by groups of countries belonging to different income bands, demonstrating specifically the rapid growth of these emissions in India and China. Macro areas World Low income countries Middle income countries Middle/low-income countries High-income countries China India growth rates CO2 emissions 0,7 2,17 1,32 1,45 0,27 1,36 1,99 Table 7: growth rates of total CO2 emissions in the period 1980-1997. Source: authors’ elaboration on World Bank data (World Bank, 2001). In the same way, the energy intensity of polluting emissions d, which had fallen significantly in the 1980s and ‘90s, is expected to grow in the next thirty years. This suggests a worsening of the sustainable development scenario despite the expected reduction in the rate of economic and demographic growth. The deterioration of energy sustainability is caused by a slight increase in the rate of growth of demand for energy and, above all, by a significant inversion of the trend in the rate of the reduction of energy intensity per unit of income and in the pollution intensity per unit of energy consumption. This deterioration of development sustainability can be made more precise by defining a sustainable energy gap g based on the identity (4): (5) g = y* - y*max = Y* - Y*max = Y* + e* + d* where y*max and Y*max define the maximum growth rate respectively of per capita income and total income that are compatible with sustainable development (i.e. the growth rates corresponding to zero environmental deterioration). With this definition, we can see that the sustainable energy gap falls from 2.8% in the 1970s to 1.6% in the ‘80s and to 1.4% in the ‘90s, but the IEA forecasts that the value will rise in the next thirty years to 1.8%. Behind these negative trends is an overly slow transition process towards an alternative model based on the massive use of renewable energies: the IEA forecasts say that the percentage of energy produced with renewable sources should increase between 2002 and 2030 from today’s 1.7% to 4.4%. The explanation set forth for such a slow transition process is generally that energy produced from fossil fuels costs less and will continue to do so for the whole period. This explanation, however, seems only partly valid. Indeed, this affirmation is based on a very unsatisfactory way of calculating the cost per kWh. First of all, no account is taken of external costs which, in the case of fossil fuels are particularly high. The increase in carbon dioxide is destined considerably to worsen global warming with all its dire consequences for the climate, the melting of glaciers, and atmospheric variability. In the second place, the production of fossil fuels can be just as dangerous in itself. It has been calculated, for example, that coal-mining alone accounts for some 10,000 deaths a year. Finally, there are also high political and economic risks connected with the predominant use of fossil fuels in that their availability is very concentrated geographically-speaking, thus creating strong tensions for the economic and political control of these areas (the Middle East in the first place).8 Given that the forecasts for the costs of each energy source are crucially dependent on the hypotheses made about economic, energy, and 8 More than 60% of the world’s oil production is concentrated in only five countries (Saudi Arabia, the United Arab Emirates, Iraq, Kuwait and Iran). If we exclude the North Sea and the USA, the remaining percentage is mainly concentrated in areas of high tension and political instability such as, for example, the west coast of Africa, Libya, Algeria, Russia and the post-Soviet republics of the Caspian. environment policies, these tensions could lead in the future to a much higher cost of energy production with fossil fuels than that being forecast today. 4 Conclusions In this paper we have seen how the conventional position on the impact of the energy sector on sustainable development seems excessively optimistic. This position affects the energy and environmental policies that are directed towards an overly slow transition process towards a new way of producing, distributing and consuming energy based on the use of renewable sources and of hydrogen. This stance is destined further to widen the sustainability gap which has characterized the last thirty years even if at decreasing rates. This seems to be confirmed by the recent IEA estimates that forecast an inversion in the future of the decreasing trend in energy and emission intensity observed over the last three decades. In recent years, the growing optimism about the market capacity to resolve spontaneously the problems of energy scarcity and pollution produced by energy consumption, has manifestly weakened policies aimed at promoting energy-saving and renewable sources. The estimates proposed in this paper indicate the urgency of strengthening the above-mentioned policies in order to accelerate the convergence towards compatibility between energy consumption and sustainable development. To this end, the choices that will be taken regarding the production and distribution of hydrogen are likely be decisive. There is already general agreement on the crucial role that this energy source will play in the future energy model, but there are profound differences of opinion between the supporters of the conventional position and its critics. The former think it best to use fossil fuels to produce hydrogen thereby risking to push the problem aside and to mitigate rather than completely resolve it. The critics of the traditional position think that oil must be produced mainly through renewable energy sources. They stress that only in this way will it be possible for hydrogen to resolve the problems of environmental degradation caused by the systematic use of fossil fuels. The use of hydrogen, in fact, should be complementary and integrated with the use of fossil fuels, in order to build up a stock of available energy from the extra energy generated in an unavoidably discontinuous way by renewable energy sources such as wind and solar power. In particular, the priority is to make provisions to accelerate the transition towards an alternative model for the production, distribution and consumption of energy. In our opinion, this model should be based on energy-saving, on incentives to the adoption of renewable sources in proportion to their external economies and on the integration of renewable energies with the hydrogen used to stock the energy produced with renewable energies. References Borghesi, S., 2001, The environmental Kuznets curve: a survey of the literature, in Franzini M., Nicita A. (eds.), “Economic Institutions and Environmental Policy”, pp.201-224, Ashgate. Previosuly published as Nota di Lavoro n.85.99, 1999, Fondazione ENI Enrico Mattei, Milano. Borghesi, S., Vercelli, A., 2003, Sustainable globalisation, Ecological Economics, vol.44, n.1, pp.77-89, Elsevier Science Ltd. Borghesi, S., Vercelli, A, Verdesca, D., 2004, Il divario di sostenibilità energetico, mimeo. 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Soytas, U., Sari, R., 2003, Energy consumption and GDP: causality relationship in G-7 countries and emerging markets, Energy Economics, vol.25, pp.33-37. Sun, J.W., 1999, The nature of CO2 emission Kuznets curve, Energy Policy, vol.27, pp.691-694. Suri V., Chapman, D., 1998, Economic growth, trade and energy: implications for the environmental Kuznets curve, Ecological Economics, v.25, iss.2 (May), pp.195-208. Ulph, A., Folie, M., 1980, Exhaustible resources and cartels: an intertemporal NashCournot model, Canadian Journal of Economics. World Bank, 2001, World Development Indicators, Washington D.C., USA. Figure 1: Annual production and known reserves of oil Figure 2: Proven reserves of oil and natural gas Source:authors’ elaboration on British Petroleum data (British Petroleum, 2003) Oil (pink) and natural gas (blue) proven reserves 1200.0 180.00 160.00 oil: billions barrrels 140.00 800.0 120.00 100.00 600.0 80.00 400.0 60.00 40.00 200.0 20.00 0.0 0.00 1980 1985 1990 period: 1980-2002 1995 2000 natural gas: trillions m^3 1000.0 Figure 3: Primary energy intensity by region over time Figure 4: Carbon intensity by region over time Figure 5: Energy intensity in selected countries over time Source: Colombo (1992) Figure 6: Figure 7: Energy-related CO2 emissions by region over time Figure 8: average growth rates in energy demand and CO2 emissions Figure 9: CO2 total emissions at world level and by income groups CO2 total emissions by income 25000 20000 15000 1980 1997 10000 5000 0 WORLD LOW INCOME MIDDLE INCOME HIGH INCOME Source: authors’ elaboration on World Bank data (World Bank, 2001).