انتشار دی اکسید کربن از بخش برق ترکیه و گزینه های کاهش آن

In this study, electricity generation associated CO2 emissions and fuel-specific CO2 emission factors are calculated based on the IPCC methodology using the data of fossil-fueled power plants that ran between 2001 and 2008 in Turkey. The estimated CO2 emissions from fossil-fueled power plants between 2009 and 2019 are also calculated using the fuel-specific CO2 emission factors and data on the projected generation capacity of the power plants that are planned to be built during this period. Given that the total electricity supply (planned+existing) will not be sufficient to provide the estimated demand between 2011 and 2019, four scenarios based on using different fuel mixtures are developed to overcome this deficiency. The results from these scenarios show that a significant decrease in the amount of CO2 emissions from electricity generation can be achieved if the share of the fossil-fueled power plants is lowered. The Renewable Energy Scenario is found to result in the lowest CO2 emissions between 2009 and 2019. The associated CO2 emissions calculated based on this scenario are approximately 192 million tons lower than that of the Business As Usual Scenario for the estimation period.

Industrialization, high population growth, and urbanization cause the depletion of natural resources and numerous environmental problems. Fossil fuel consumption, as a depletion of natural resources, results in the increase of greenhouse gas (GHG) emissions in the atmosphere. The concentration of atmospheric CO2, which is the major GHG, has increased from a pre-industrial value of approximately 280–379 ppm as of 2005 (IPCC, 2007). Changes in sea level, snow cover, ice sheets, and rainfall are results of global climate change, and all these disasters affect ecosystems in many parts of the world (UNFCCC, 2006). Because the climate change problem threatens all living beings, the solution to this problem needs to be dealt with globally. Thus, the United Nations took a step to handle this global problem at the United Nations Framework Convention on Climate Change (UNFCCC). The ultimate objective of the UNFCCC is to stabilize the GHG concentration in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. To accomplish this task, significant GHG emission reduction is required (IEA, 2009). As a party to UNFCCC and Kyoto Protocol, Turkey has been keeping track of her GHG emissions since 2006. According to the national GHG emission inventory of Turkey, GHG (CO2, CH4, N2O, HFC, PFC, and SF6) emissions have increased 95% from 187 to 366.5 million tons CO2 eqv. between 1990 and 2008. The CO2 emissions for the same period increased from 141 to 297 million tons. In addition, the CO2 emissions from electricity generation increased 234% from 30.3 to 101.5 million tons for the same period, covering, on average, approximately 30% of the total CO2 emissions in Turkey. Consequently, the electricity generation between 1990 and 2008 in Turkey increased 244% from 57,543 to 197,839 GWh (UNFCCC, 2010). A reduction in electricity generation-associated CO2 emissions can be achieved by increasing the usage of renewable energy sources, such as wind, geothermal, hydro, and biomass, for power generation. There are currently only a few studies on the relationship between electricity generation and the associated CO2 emissions in Turkey. These studies are generally national reports, such as the National Inventory Report (NIR) and the First National Communication submitted to the UNFCCC secretary due to certain responsibilities of Turkey. The methodology of calculating the GHG emissions in these reports depends on the Intergovernmental Panel on Climate Change (IPCC) approach, which is a top–down approach that does not differentiate IPCC default emission factors according to the low heating value (LHV) of each type of fuel. The major objective of this study is to investigate the mitigation potential of CO2 emissions from electricity generation using renewable energy sources over the next decade. To achieve this objective, CO2 emissions from fossil-fueled power plants that ran between 2001 and 2008 are calculated, and then using these results, the country-specific emission factors for each fuel type are calculated. To the authors' knowledge, this is the first study that is based on calculating the total electricity generation-associated CO2 emissions using data that cover all currently running power plants and that presents country-specific emission factors for Turkey for each fuel type based on current power plant data. These fuel-specific emission factors and the estimated amount of electricity that will be generated by the planned power plants are used to determine the electricity generation-associated CO2 emissions in the next decade. To date, efforts to investigate future electricity generation and the associated CO2 emissions in Turkey have been limited. Studies conducted by the Ministry of Environment and Forestry (MoEF) (2006), Greenpeace (2009), and Turker (2008) are among those on the developing future electricity demand and the associated CO2 emissions for Turkey. Different alternatives are used to supply the needed electricity demand and the associated CO2 emissions in these studies; however, the official licensed and planned power plant data were not considered for calculating the supply side of the electricity demand and its associated CO2 emissions, as is done in this study. The power plant data used in this study are gathered from the National Load Distribution Center (NLDC) in Turkey (NLDC, 2009). The default emission factors and the calculation of the CO2 emission methodology are based on IPCC Guidelines (IPCC, 2006). The low heating value of each fossil fuel and the thermal efficiency data of the fossil-fueled power plants in Turkey are obtained from various sources in the open literature. The estimated electricity demand between 2009 and 2018 is obtained from the Turkish Electricity Transmission Company (TETC, 2009). The planned and licensed power plant data with information on their completion are obtained from the Energy Market Regulatory Authority (EMRA, 2009).

This study investigates the mitigation potential of CO2 emissions from electricity using renewable energy sources for the shortfall amount between the estimated demand and supply (planned+existing). To the authors' knowledge, this is the first comprehensive study that analyzes the associated CO2 emissions from electricity generation using the data available from each of the major power plants in Turkey between 2001 and 2008, calculates the specific emission factors by fuel type using this power plant data, determines the amount of electricity that will be generated by fuel type annually between 2009 and 2019, and analyzes the amount of associated CO2 emission reduction with available and economically feasible renewable sources. In the first part of the study, the generated electricity based on fuel type, associated CO2 emissions, and fuel-specific emission factors are calculated. Based on these calculations, the amount of total electricity generated increased from 122,311 to 197,839 GWh between 2001 and 2008 in Turkey, which corresponds to a total increase if 62% for this period. For the same period, the associated CO2 emissions increased by approximately 55%, from 68 to 106 million tons. The fuel-specific emission factors for Turkey are also generated. The results show that lignite and hard coal have the highest fuel-specific emission factors among the other fossil fuels, at 1080 and 1018 kg CO2/MWh, respectively. The specific emission factor for natural gas is calculated as 374 kg CO2/MWh, which is lower than that of lignite and hard coal. In the next part of the study, the power plants that are planned to be built in Turkey between 2009 and 2019 are analyzed. The results show that it is mainly plants using natural gas, hydro, and coal that are expected to be built in this period. The amount of electricity that is estimated to be generated from the existing and planned power plants is found to be lower than the estimated demand for this period, which means new power plants need to be built. In the last part of the study, four scenarios are developed to supply the shortfall amount of the total supply, namely, the Business As Usual, Renewable, Fossil Fuel, and Natural Gas scenarios. The amounts of electricity generated by fuel type and the associated CO2 emissions based on each scenario are also determined. The total electricity generation-associated CO2 emissions based on the Business As Usual, Renewable, Fossil Fuel, and Natural Gas scenarios between 2009 and 2019 are given in Fig. 8. As seen here, the Renewable Scenario has the least CO2 emissions at 1,368 million tons; the Natural Gas Scenario follows the Renewable Scenario, with 1507 million tons of CO2 emissions; and the Fossil Fuel Scenario has the highest CO2 emissions, with 1600 million tons between 2009 and 2019. In terms of the mitigation of CO2 emissions, the scenario with the lowest emissions is the Renewable Energy Scenario. This scenario provides a reduction of 192 million tons of CO2 emissions with respect to the BAU Scenario between 2009 and 2019. In climate change negotiations under the UNFCCC, this amount could be declared as the deviation of CO2 emissions from the business as usual conditions. In addition, Turkey could use this mitigation potential to benefit from flexible mechanisms in the climate change issue, such as emissions trading. The renewable energy scenario also provides an increased share of national energy sources in electricity generation with the hydro, geothermal, wind, and biomass potentials of Turkey, which would also reduce the energy dependency on foreign sources. In a possible future study, the IPCC Tier-3 approach, which includes combustion technology, operating conditions, and age of equipment, among others, can be used to calculate the associated CO2 emissions if the required data become available in the future. In addition, with these analyses, the CO2 mitigation potential by carbon capture, storage, and sequestration technologies in the electricity sector can be examined especially for hard coal and lignite fossil-fueled power plants in Turkey. The economic costs and cost/benefit analyses of these scenarios can also be assessed if the required data become available in the future.