کاهش تولید گازهای گلخانه ای و پیامدهای اقتصادی نفوذ در بازار انرژی تجدید پذیر و تولید برق برای مصارف خانگی در منطقه خاورمیانه و شمال آفریقا
|کد مقاله||سال انتشار||مقاله انگلیسی||ترجمه فارسی||تعداد کلمات|
|16572||2013||10 صفحه PDF||سفارش دهید||6500 کلمه|
Publisher : Elsevier - Science Direct (الزویر - ساینس دایرکت)
Journal : Energy Policy, Volume 52, January 2013, Pages 618–627
This paper examines the implications of renewable energy (RE) deployment in power generation for residential consumption in the Middle East and North Africa (MENA) region under various RE penetration targets. A comparative assessment revealed a great heterogeneity among countries with Turkey dominating as the highest emitter. At the sub-regional level, the Middle East sub-region contributes more than double the GHG emissions estimated for the Gulf and North Africa sub-regions with all sub-regions achieving reductions in the range of 6–38% depending on the RE target penetration and promising up to 54% savings on investment excluding positive externalities associated with the offset of greenhouse gas (GHG) emissions savings.
Historically, the use of fossil fuels has dominated the energy supply to meet the continuously increasing energy demand for economic and human development worldwide. Provision of energy services including power generation, however, has greatly contributed to the increase in anthropogenic greenhouse gas (GHG) emissions and concentrations in the atmosphere, resulting in global warming and climate change (IPCC, 2007). World statistics show that in four years (2004–2008), while the world population increased by 5%, the gross energy production and annual CO2 emissions increased by 10%, reaching 12 billion tons of oil equivalent of total primary world energy supply and 29.4 billion tons of CO2 emissions in 2008 (IEA, 2010). By the end of 2010, ambient CO2 concentrations have reached ∼390 ppm (39% above pre-industrial levels) and continue to rise (IPCC, 2011 and NOAA, 2010). With lower carbon intensity in emissions per energy output, renewable energy (RE) sources are promoted worldwide as measures to mitigate climate change (IPCC, 2011). Beyond emissions' reductions, investment in RE is highly driven by efforts for social and economic development due to associated benefits including environmental protection, diversification, and economic gains. It is estimated that various RE sources accounts for 14% of worldwide total primary energy supply, with a potential to reach ∼50% of the global energy demand by 2050 (Bilen et al., 2008). Research on the development, application and implications of RE systems is continuously growing (Lin et al., 2010, Akella et al., 2009, Manish et al., 2006 and Tsioliaridou et al., 2006). A plethora of studies have also investigated the benefits of RE use on energy production and GHG emissions reduction, mainly, through simulating scenarios of RE penetration (Foyn et al., 2011, Blumsack and Xu, 2011, Chiu and Chang, 2009, Tsoutsos et al., 2008, Cai et al., 2007 and Chedid et al., 2001). Common tools and models of energy input and output analysis used for RE penetration simulations include Energy PLAN and LEAP (Connolly et al., 2010, Lund and Mathiesen, 2009 and Giatrakos et al., 2009). Simulation studies reported potential GHG emission reductions worldwide ranging from as low as 4.8% by 2020 in South Korea (Jun et al., 2010) to as high as 40–45% in China (Shan et al., 2012 and Liu et al., 2011) under different economic growth and RE supply scenarios. A 32% reduction in emissions was estimated for Mexico by 2025 (Manzini et al., 2001) while an 11.2–35% emission reduction from the electricity generation only was foreseen for Lebanon under different RE use scenarios (Dagher and Ruble, 2011 and El Fadel et al., 2003). Similar results were reported for various developing and developed countries i.e. Sri Lanka, Thailand, Cyprus, Greece, Denmark, Norway and G7 countries (Gebremedhin and Granheim, 2012, Tsilingiridis et al., 2011, Wijayatunga and Prasad, 2009, Sadorsky, 2009, Tanatvanit et al., 2003, Tsoutsos et al., 2008 and Lund and Mathiesen, 2009) as well as for the global energy system (Foyn et al., 2011 and Krewitt et al., 2009). In parallel, high initial RE investment needs were invariably highlighted, with a potential to delay and discourage wide RE deployment (Shan et al., 2012, Liu et al., 2011, Jun et al., 2010, Wijayatunga and Prasad, 2009 and Cai et al., 2007). With a relative lack of studies on the implications of RE use in the Middle East North Africa (MENA) region, this paper focuses on the potential benefits of RE deployment in the power generation (electricity) sector in this region. It explores the potential of renewable resources to meet the latent and growing residential demand for energy while providing socio-economic benefits to individual countries and the region. It examines environmental and economic implications of RE deployment by relying on long term simulations of GHG emissions under several scenarios on a country by country and sub-region basis.
نتیجه گیری انگلیسی
The main data compiled from secondary sources and reasonable estimates are summarized on a per country basis and were relied upon as input parameters for LEAP simulations, “see Electronic Appendix A in the online version of this article”. 3.1. Country level analysis The simulation of GHG emissions for individual countries under the Policy and Revolution scenarios revealed a great heterogeneity among countries in terms of GHG emissions, RE penetration targets, and associated emissions reductions. Naturally, GHG emissions increase with population, urbanization, usage of non-renewable energy sources, and terawatt-hours production. Fig. 2 depicts the residential electricity demand per country for 2010 (base year) as well as that projected for 2040 (end year). Generally, in parallel with the increase in residential power demand, all countries showed a reduction in emitted GHGs under the mitigation scenarios, with great variations among countries and between the Policy and Revolution scenarios. Being highly dependent on coal, the conventional energy source with the highest GHG emissions rate, and further augmented by the relatively higher residential demand, Turkey stands out by far as the highest emitter of GHGs in the region with Iran, Egypt, UAE, KSA and Kuwait exhibiting high contributions amongst the remaining countries. Fig. 3 depicts the GHG emissions produced from the electricity sector (for residential demand) on a country by country basis in million tons of carbon dioxide equivalents (MtCO2e) at the end year under the simulated scenarios. Turkey is not shown graphically because it has a larger emission equivalent compared to other countries of the region. Table 4 summarizes the percent reduction in GHG emissions per country as well as the per capita impact under the simulated scenarios. Under the Policy scenario, the national GHG emissions as forecasted for 2040, the end of the simulation period, ranged from as low as 1.2 MtCO2e in Jordan to as high as 65 MtCO2e in Turkey whereas the corresponding reduced GHG emissions at the national level ranged from as low as 0.1 MtCO2e in Bahrain (a reduction of 4%) and Tunisia (6%) to as high as 17 MtCO2e in Turkey (21%). This wide range in emissions is directly related to the combination of energy sources used in addition to the country specific residential demand parameters. The percentage reductions in GHG emissions estimated under the Policy scenario, in comparison to the Reference scenario, ranged from as low as 2% in Israel to as high as 50% in Lebanon. This significant 50% reduction is directly related to the total phase out of oil from energy sources to be used for residential electricity generation in Lebanon. Lebanon, thus, exhibits more promise than estimated reductions by Dagher and Ruble (2011) at 11% and El-Fadel et al. (2003) at 35%, as a function of considered shares of fossil and non-fossil sources. Nevertheless, this is translated into 0.33 tCO2e/capita or about 53% reduction from its current emissions rate. Note that Bahrain, Iran, Iraq, Israel, Kuwait, KSA and Tunisia are not expected to achieve more than 9% reduction in GHG emissions because of their shy RE targets. This translates into 1.57 and 1.12 t of carbon dioxide emissions per capita (tCO2e/capita) for Bahrain and Kuwait respectively (Table 4) reflecting that under the Policy scenario, the bulk of energy production in Kuwait and Bahrain remains heavily dependent on fossil fuels. Although the emissions per capita for Bahrain under the Policy Scenario are relatively high, they are ∼80% lower than the current emissions per capita rate of 2.82 tCO2e. On the other hand, Morocco, Oman, Jordan, Algeria and UAE are to achieve reductions in GHG emissions in the range of 10–20%, based on their RE targets. This is translated into <0.1 tCO2e emissions per capita for all these countries except Oman (0.5 tCO2e) and UAE (1.22 tCO2e) (Table 4). The current (2010) estimated emissions per capita for UAE and Oman are 2.8 and 1 tCO2e indicating a significant reduction in tCO2e per capita, under the policy scenario, of 57% and 50%, respectively. Note that although UAE (Abu Dhabi) is targeting nuclear power plant projects to operate starting 2020, nuclear energy as a non-renewable alternative was not included in the sub-regional and regional analysis of this study to avoid distortion of the results by its low carbon emissions that mask its potential adverse environmental externalities including radioactive/hazardous waste generation. However, at the UAE country level, simulations to test for the impact of including nuclear energy sources for power generation revealed 17.8% and 45.2% reduction of GHG emissions under the policy and revolution scenarios, respectively for the whole simulation period (Fig. 4). Accordingly, penetration of RE alone within the Revolution scenario achieves ∼50% more reduction in GHG emissions than a combination of both under the Policy scenario. Note that, the 45% reductions promised in the combination of 25% nuclear and 66% RE share is challenged by the risks and potential adverse environmental externalities associated with the operation of nuclear power plants. Hence, at the level of decision making, the additional reduction in GHG emissions of 13–16% as well as the economic benefits accomplished by introducing nuclear energy in UAE should be weighed against potential risks and associated externalities. Under the Revolution scenario, national GHG emissions of MENA countries, as forecasted over the simulation period, ranged from as low as 0.5 MtCO2e in Jordan to as high as 35 MtCO2e in Turkey whereas the corresponding GHG emissions reduction at the national level ranged from as low as 0.2 MtCO2e (∼13%) in Morocco to as high as 47 MtCO2e (57%) in Turkey. The percent reduction under the Revolution scenario as compared to the Reference scenario is naturally similar for most countries at a range of 57–75% reflecting the flat RE share of 66%. This is also translated into much lower CO2 emissions per capita for all countries for the year 2040 under this scenario (Table 4) ranging from as low as 0.03 tCO2e for Morocco to 0.46 tCO2e for UAE. It was also observed that compared to the Policy scenario, the Revolution scenario aids countries in achieving an additional significant reduction in GHG emissions in the range of 45–65% in all countries except Morocco. As the actual targets for Morocco under the Policy Scenario are close to the 66% flat rate applied under the Revolution Scenario, only 4% additional reduction is observed. Accordingly, national emissions per capita in the MENA countries would range from 0.03–1.57 tCO2e and 0.03–0.46 tCO2e under the Policy and Revolution scenarios respectively. These values are lower than those reported for China at 12.1 tCO2e/capita by 2050 (Lin et al., 2010) and Mexico at >5 tCO2e/capita by 2025 (Manzini et al., 2001) reflecting on peculiarities of individual countries but comparable to the global average estimated at 1.15 tCO2e/capita by 2050 (Krewitt et al., 2009). As expected, it is apparent that the heterogeneous combinations of energy sources in the MENA countries as well as local residential demand peculiarities have played the critical roles in defining emissions reductions in individual countries. Countries that replaced coal and oil sources by RE sources exhibited steep reductions in GHG emissions (Lebanon), particularly in comparison to countries that shifted from natural gas to RE sources (Syria), where the impact on emissions reductions was not as pronounced, necessarily as a function of the GHG emission rate per conventional energy source. Similarly, countries still dependent on coal (Turkey) and oil (KSA, Iraq) exhibits a continuation of relatively high emissions. 3.2. Sub-regional analysis Simulations of reductions in GHG emissions at the sub-region level revealed important differences among the sub-regions. Fig. 5 shows the amount of MtCO2e emissions produced by the sub-regions under different scenarios for the whole simulation period and the estimated percent reduction in GHG emissions. Under the Policy scenario, where every country introduces RE shares based on its own set targets which vary in stringency and conservativeness, the North Africa and Gulf sub-regions are projected to emit about 872 MtCO2e and 1483 MtCO2e of GHG emissions respectively. This accounts for 2–3 times less than emissions of the Middle East sub-region (2993 MtCO2e) because the latter includes Turkey and Iran, two large emitters dependent on coal and oil respectively, constituting ∼50% of the region's total emitted GHGs. Nevertheless, the Middle East would achieve 9% reduction in GHG emissions under the Policy scenario as compared to the Reference scenario. While the Gulf seems to emit the lowest amount of GHGs by 2040, it only accomplishes 6% reduction in emissions and North Africa is observed to a 12% reduction. Evidently, more loose or stringent targets at any country level will change the general scene at the sub-region and regional level. On the other hand, under the RE Revolution Scenario where a flat rate of 66% RE share is applied, a significant reduction in GHGs emissions is expected in all sub-regions. Under this scenario, North Africa, the Middle East and the Gulf sub-regions are forecasted to emit 664, 1034 and 2226 MtCO2e, respectively. Under this scenario, the sub-regions achieve comparable emission reductions that vary from 32% for the Middle East to 38% for North Africa. The Revolution Scenario grants each sub-region an additional30% decrease in GHG emissions to those expected under the Policy scenario. Comparison among the three sub-regions, despite the great heterogeneity among constituent countries, is more valid under this scenario due to the flat RE share common to all countries, whereby the comparable significant reduction in GHG emissions would infiltrate social benefits at the local, sub-regional and regional level. 3.3. Regional analysis When countries in the MENA region achieve their set targets (or proposed targets) of RE contribution in electricity production, the region will benefit from a total GHG emission reduction of 477 MtCO2e, constituting about 8% reduction from the Reference Scenario (Fig. 6). If MENA adopts a revolutionary flat share of 66% RE in electricity production to all its constituent countries, then the region has the potential of benefitting from a total reduction in GHG emissions of 1900 MtCO2e, consisting of about a significant 36% decrease from the Reference Scenario. Accordingly, this infers that collaboration among countries and a commitment to mainstream RE in their heterogeneous energy structures is an indispensible step towards efficient GHG reductions, particularly in view of the unbalanced targets individually set by countries that at the regional level might mask local efficient reductions. 3.3.1. Economic implications The high potential of GHG emission reductions in the MENA countries associated with the use of renewable energy sources in electricity production for residential consumption promotes further deployment of RE in the region. However, this is likely to be constrained by a relatively high initial investment. Fig. 7 summarizes the estimated electricity generation costs (reference year 2010, discount rate 8%) over the whole projection period (2010–2040) under each scenario per sub-region and MENA region. Evidently, the total cost of electricity production is different among sub-regions of MENA with variations in the magnitude of change in the cost of generation under the different scenarios. Fig. 8 illustrates the % reduction in investment needed under Policy and Revolution RE deployment scenarios over the 30 years simulation period. The negative percentage reveals an additional cost or an increase in investment, while positive percentages reveal savings in investment. In North Africa (NA), the RE Revolution scenario appears to be cheaper by at least 45%, at the side of the minimum cost of investment, whereas the Policy scenario is 0.5% more expensive than the Reference scenario. At the side of the maximum cost, the Revolution scenario remains the cheapest scenario (∼54% less than the Reference scenario), while the Policy scenario is 3% more expensive. While this might seem counter intuitive, note that major RE sources in North Africa are solar, known to have high initial costs but low operational costs, which explains the financial viability with increased use over a long period. With a potential 54% reduction in cost and a potential 38% decrease in GHG emissions, the RE Revolution scenario emerges as an efficient scenario in the North Africa sub-region. With respect to the Gulf Countries, the policy scenario requires a lower investment than the reference scenario in the range of 2.3–3.7% over the total simulation period (30 years). However, the RE Revolution scenario stands as a very competitive scenario with potential savings on investment in the range of 20–18% in comparison to the Reference scenario, keeping in mind its 35% potential GHG emission reductions. In the Middle East (ME) sub-region, the cost of electricity generation also decreases with the increase in the share of RE. It is shown that the increased reliance on RE, which has relatively lower operational costs despite its high capital costs, becomes financially more viable over the long run. This has also been noticed in the comparative LCOE of RE with conventional sources presented in Table 3. At the minimum cost side, savings on investment of about 13.9% (227 billion USD) in the ME is associated with the implementation of the Policy scenario, while about 19.7% (360 billion USD) is associated with Revolution Scenario implementation. At the maximum cost side, about 4.3–10% saving of investments are associated with the Policy and Revolution Scenarios implementation respectively. Hence, with a 10–19.7% saving on investment, with a potential 32% reduction in GHGs, the Revolution Scenario emerges as the optimal scenario for the Middle East sub-region as well. At the MENA region as a whole, the investment required for RE deployment, over the total simulation period of 30 years, ranges from 2861-7247B USD for implementing the Policy Scenario, and from 2406-6086B USD for implementing the RE Revolution RE (Fig. 7). With the current estimated MENA GDP of about $2 trillion USD (WB 2010), investment in RE under any scenario would constitute 7–12% of the region's GDP. Although this seems high however it actually manifests itself as savings on investment of 2.7–8.5% for implementing the policy scenario and up to 18.3–23.1% for implementing the Revolution scenario in comparison to the currently implemented reference scenario (Fig. 8). Hence, increased RE penetration in power generation for residential consumption in the MENA region is justifiable by the multitude of social benefits associated with RE including the 8–36% GHG emissions reductions, green jobs, sustainable energy, and energy security and economically viable. Equally significant, are positive externalities associated with the offset of GHG emissions through regulated and voluntary global carbon markets that allow trading, selling, buying and offsetting of carbon credits. The latter was initiated as part of the Clean Development Mechanism (CDM) and Joint Implementation (JI) mechanisms but has become a global as well as an individual incentive to reduce carbon footprint. Accordingly, based on carbon market price (Ecosystem Marketplace, 2011), the avoided GHG emissions under RE deployment could be quantified (Table 5) under the Policy and Revolution RE scenarios. They were estimated at 0.01–0.06% of MENA region GDP for the year 2010. When these carbon credits are actually sold or if taxes are set to limit emissions to quantities produced under the Policy and Revolution scenarios, then their revenues, calculated as social benefits, would be subtracted from the RE investment rendering the investment in RE more economically attractive. Table 6 illustrates the example of the MENA sub-regions where positive externalities of taxing GHG or selling credits of GHG avoided could reduce the total cost of electricity generation under increased RE shares. The estimated percent savings from cost adjustment ranged from 0.12–1.56% in the sub-regions, and from 0.37–0.53% in the whole region naturally increasing with the increased deployment of RE under the Revolution scenario. Other un-accounted for externalities that distort the above cost benefit analysis include the damage cost resulting from the combustion of fossil fuels in terms of health and environmental impacts. If these costs are internalized into the output price of electricity, then the total cost of electricity production from fossil fuels in the Reference scenarios would be higher, therefore, increasing the economic viability of RE. Moreover, while the initial investment in RE is relatively high, it is expected to decline with technology advances and economies of scale which will further facilitate and catalyze the shift to RE at the local and global levels.