Analysis of green-house gas emission in China

Transcription

1 Analysis of green-house gas emission in China TKEMM Master thesis Yulin Li

2 Preface This report was written as a part of master thesis of Chemical Engineering for Energy and Environment at The Royal Institute of Technology, Stockholm, Sweden. The aim of the report is to analyze current Chinese GHG emission and forecast the future tendency of that. i

3 Abstract Today China produces most GHG emissions in the world, which continues increasing the average temperature of the Earth. For the purpose of reducing the emission and reaching the peak of GHG emission before 2030, Chinese government promotes several policies, such as developing renewable energy, importing advanced emission reduction technology and encouraging the production and sales of new energy vehicles. In order to estimate the tendency of Chinese GHG emission, a review has been conducted. This review has considered the current Chinese situation, making necessary assumptions and calculating total emission in several relevant sectors independently. By adjusting several key figures, the end result of peak year may be changed. The review has proved that the peak year for Chinese GHG emissions will be 2035 under normal condition. If other optimized factors are considered, the peak year could be moved up. ii

4 Table of content Preface... i Abstract... ii Table of content... iii 1. Introduction Definition of GHG Global background Chinese current situation Aim of the report Electricity production Electricity demand Nuclear power Hydro power Wind power Solar power Thermal power GHG emission from electricity production sector Industry Emission from burning of fossil fuel Emission from coal mining escape Emission from cement production Emission from lime production GHG emission from industry sector Agriculture Emission from crop farming Emission from livestock Emission from fossil fuel use iii

5 4.4 Emission from biomass GHG emission from agriculture sector Transportation GHG emission from transportation sector Other sources Construction emission Commercial emission Life emission Garbage disposal Forestry Advanced technology Energy storage Tidal power Geothermal power Biomass Pinch Point technology Total emission Normal condition Condition with advanced technology Condition with double wind turbine construction Condition with double wind turbine and nuclear unit construction Condition with half GDP increasing rate Condition with 1.25 times new energy vehicle improvement Combination of all conditions Discussion Conclusion Reference iv

6 Appendix Appendix Appendix Appendix Appendix Appendix Appendix Appendix v

7 1. Introduction 1.1 Definition of GHG Greenhouse gases (GHG) widely exist in atmosphere, mainly as steam, carbon dioxide, methane and ozone. Those gases could cause greenhouse effect by absorbing and emitting radiation from the Sun. Without the protection of GHG, the temperature of the Earth surface would be about -18 o C, rather than present of 15 o C [1]. Thus, presence of GHG is a key factor of the present ecosphere. After five billion years of circulation, GHG in the atmosphere remains in a dynamic equilibrium state, which avoids a dramatic change of temperature on the Earth. However, due to the burning of huge amounts of fossil fuels by human, the absorption of GHG by environment is much smaller than the emission of that. Those human activities cause that additional GHG accumulates in atmosphere and, furthermore, prohibits extra heat losing into universal. The average temperature of the Earth will increase, because of extra heat presence in atmosphere, which leads to glacial melting, sea-level raising, low-land flooded and so on. Six types of greenhouse gases are usually counted into emission estimate, including carbon dioxide (CO 2 ), methane (CH 4 ), nitrous oxide (N 2 O), chlorofluorocarbons (CFCs) and hydro-fluorocarbons (incl. HCFCs and HFCs). Meanwhile, global warming potential (GWP) and global temperature change potential (GTP), shown in Table 1, are always used to measure the contribution of GHG. In order to uniform standard, all the results will be transforming to GWP 20 in this report. Table 1. GWP and GTP of five main greenhouse gases [2] GWP 20* GWP 100 GTP 20 GTP 100 CO CH N 2 O CFCs HFCs *The global warming potential in 20 years. Although there are a lot of emission sources of GHG, burning of fossil fuel is the main path [3]. On the other way around, from all over the world, the main emission of GHG is CO 2, since carbon is the fundamental element of coal, oil and natural gas. The other two key emissions are CH 4 and N 2 O, mainly emitted by agricultural and coal mining escape. Comparing with CO 2, CH 4 and N 2 O, the quantity of rest three gases 1

8 are far more less, even though they could lead to greater damage with same weight. The proportion of several GHG in total emission is shown in Figure 1. Figure 1. The proportion of several GHG in total emission [3] 1.2 Global background Since the industrial revolution in 1750s, the concentration of carbon dioxide in the atmosphere has increased by 40 % caused by human activities, from 280 ppm (Part Per Million) in 1750 to 406 ppm in 2017 [4]. The majority of carbon emissions comes from the burning of fossil fuels and those activities include electricity production, industry, agriculture, transportation etc. The proportion of each sector in total emission, presented by the Environmental Protection Agency, is shown in Figure 2. Figure 2. The proportion of each sector in total emission [3] 2

9 Among those emission sectors, emission from electricity production is produced by burning of coal, oil and natural gas in thermal power plant. In the industrial sector, emission results of direct combustion of fossil fuels on site, as well as by-production of industry process. GHG emission from agriculture mostly comes from cultivation of crops and livestock. Transportation GHG emission primarily involves fossil fuels burned for road, rail, air, and marine transportation. Above four sectors contain about 85 % emissions in all over the world. Global GHG emission is 4.05 Gton at seventies of last century, and by 2010s GHG emissions have risen to 9.13 Gton [5]. The growth rate of GHG emissions has considerablely increased in this century, and GHG emissions in the past four decades have been almost half of the total emissions since If the growth of carbon emission continues like this, the temperature of the Earth will exceed the historical highest point in 2047, which will have a serious impact to the entire ecosystem [6]. In order to avoid that situation, all countries and organizations around the world should limit their carbon emission. In 2010s, several of world's largest carbon producers are China, the United States, the European Union, India, Russia and Japan [3]. In contrast, those contraries represent three kinds of energy consumption mode: oil mode, most developed countries are of this type, like the United States; coal mode, such as China, more than 67 % of energy consumption is coal; nuclear mode, like France, the proportion of nuclear power in France more than 78 % [7]. The variety of carbon emission of several countries from 1970 to 2012 is shown in Figure 3. Figure 3. The variety of carbon emission of several countries from 1970 to 2012 [8] 3

10 1.3 Chinese current situation China has become the country with largest carbon emissions in all over the world since 2007 [8]. With incomplete statistics, Chinese carbon emissions from fossil fuels and from the cement industry were 8.5 Gton in On contrary, Chinese total carbon emissions in 1950 was only 5.46 Mtons, which means it has grew by more than 100 times during 60-year period from 1950 to 2012, and the growth rate was much higher than that of the rest of the world. By 2012, the total amount of carbon emissions in China has been equivalent to the sum of United States and Europe emissions. As a matter of fact, Chinese carbon emission was driven by highly economic growth for more than 30 years and it has tripled in a decade after entering 21 st century. From 2010 to 2012, 73 % of the world's carbon emissions growth was from China [8]. With incomplete statistics, the carbon emissions of China are mainly from fossil fuel combustion (90 %) and cement production (10 %) [8]. In 2012, 90 % of China's carbon emissions came from fossil fuel combustion, of which 68 % came from coal, 13 % came from oil, and 7 % came from natural gas. China, as a coal-base country, produced 3.5 Gton of coal in 2012, accounting for half of the world's total production and 1.5 Gton of cement, accounting for 60 % of the world's total output [8]. The cement production of China from 2010 to 2012 was over that of the United States in the whole 20 th century [8]. The amount of carbon emission from several sources from 1997 to 2012 is shown in Figure 4. Figure 4. Amount of carbon emission from several sources from 1997 to 2012 in China [8] 4

11 Among all sectors, manufacturing and thermal power generation contribute the most carbon emissions. In 2012, 47 % of Chinese total carbon emission was from manufacturing and carbon emission from thermal power industry was accounted for 32 % of that. As a comparison, transport sector emission was only 6 % of the total carbon emissions, which is very different with the global proportion. Furthermore, comparing with western developed countries, the proportion of each sector is not the same. For example, in the United States, 32 % of carbon emission comes from the transport sector and only 17 % in manufacturing [8]. This difference reflects the status of China as global manufacturing centers and "world factories" in past 10 years. China has gathered major global manufacturing activities, for example, China's coal, coke, steel, cement and glass production exceeded more than half of global production. The proportion of carbon emission of several sectors is shown in Figure 5 Figure 5. Proportion of carbon emission of several sectors in China [8] There are two reasons that might explain why Chinese carbon emission has such rapidly high growth rate. On the one hand, Chinese industrialization process is only a few decades, which is still in the stage of rapid development. Once the infrastructure construction, urbanization and industrialization are completed, Chinese emission will reduce. On the other hand, 96 % of Chinese energy reserve is coal, which means oil and gas resources only occupy 4 % of the total reserve [7]. As can be seen from Table 2, approximately 70 % of Chinese energy consumption is coal. The proportion of coal is almost 2.5 times as big as the world s average proportion. However, in order to get the same calorific value, GHG emissions of coal are 1.24 times as big as that of oil and 1.75 times as big as that of natural gas. Thus, Chinese energy consumption structure will undoubtedly increase carbon emission. 5

12 Table 2. Coal consumption and proportion from 2010 to 2015 [7] Year Coal consumption (Mtons SCE*) Proportion * Standard Coal Equivalent In order to reduce GHG emission, Chinese government has release several policies to promote the process in different sectors. Firstly, in electricity production sector, nuclear power, wind power, solar power and other renewable energy are dramatically developing in China, to replace coal-fire energy plant. Also, technological innovation of thermal power generation, such as ultra-supercritical technology, can effectively reduce carbon emissions [10]. Secondly, in industry sector, promoting foreign advanced technology could decrease GHG emissions. For example, there are two ways in coal mining, downhole mining and open pit mining. Compared with open pit mining, downhole mining is more popular in China, but will emit much more methane during mining process. So, it is meaningful to replace downhole mining by open pit mining. Thirdly, in agricultural sector, the application of fertilizer should be used more suitable. Fourthly, in the transportation sector, new energy vehicle has gradually begun to enter people's vision. Until January 2017, promoted by Chinese government, people have maintained over 1 million new energy vehicles in China [11]. Finally, Chinese government is promoting a program that wasteland and farmland to grass and forest since 1999 [12]. This plan will greatly increase the amount of carbon dioxide absorption. 1.4 Aim of the report The aim of the thesis will be to analyze the situation in China and discuss whether the claim if China could reach peak of greenhouse gases emission before 2030 is possible. In this report, several sectors, including electricity, industry, agriculture, transportation and forest, will be researched separately. 6

13 2. Electricity production Coal, as Chinese main energy source, acts an important role in both thermal power generation sector and industry on site combustion sector. So far, thermal power is still Chinese main source of generating electricity, which is different from most developed countries. For example, French nuclear energy covers 75 % of total electricity demand and Brazilian hydropower covers more than 80 % of that in Brazil [13] [14]. However, in China, the proportion of thermal power in total electricity production is over 75 % [15]. Although China has the largest hydropower station and highest hydropower installed capacity in the world, hydro power station could only satisfy 20 % of electricity demand of China. With a large number of populations, Chinese electricity demand is much higher than other countries. Fortunately, in order to decrease GHG emission from coal-fire energy production, development of nuclear power, wind power and solar power is strongly promoted by government. As shown in Table 3, these three new renewable energy sources, driven by the government, are gradually increasing their proportion of electricity production. Table 3. Production and proportion of several electricity source from 2010 to 2014 [15] Year Total production (TWh) Thermal (TWh) Thermal proportion Hydro (TWh) Hydro proportion Nuclear (TWh) Nuclear proportion Wind (TWh) Wind proportion Electricity demand As shown Table 4, the growth rate of Chinese electricity demand was in a rapidly increasing stage before The average annual growth rate was more than 10 % [15]. After that, due to the impact of global recession and Chinese own industrial restructuring, the average annual growth rate was dropped to about 5 %. Although the electricity consumption per capita of Chinese is higher than that of global human beings, it is still far away from those developed countries. In other words, Chinese 7

14 electricity demand will continue increasing. In order to predict the future trend of that, some assumptions will be needed. Table 4. Electricity demand and average increasing rate from 1990 to 2015 Year Electricity demand (TWh) Average increasing rate Assuming the behavior of growth rate of electricity demand in each country is basically the same. And then, in order to forecast the future growth rate of Chinese electricity demand, several countries should be considered as model. The electricity consumption, energy demand per capita, area and population density of several countries in 2015 is shown in Table 5. Rank Table 5. Electricity consumption, energy demand per capita, area and population Country/Region density of several countries in 2015 [15] [16] [17] Electricity consumption (GWh/yr) Energy demand per capita (kwh) Area (km 2 ) Population density (person/km 2 ) World 21,776,088 2, ,940, China 5,919,800 4,310 9,640, USA 3,913,000 12,077 9,833, EU 2,771,000 5,391 4,475, Russia 1,065,000 7,481 17,098, India 1,001, ,287, Japan 934,000 7, , Germany 533, , Canada 528, ,984, Brazil 518, ,515, North Korea 495, , France 431, , From above table, three countries are selected as models. First, the United States, owning similar geographical latitude span with China, is a highly developed country. The peak of electricity demand of US has been reached in 2005, shown in Figure 6, and then, its electricity consumption maintain at that level [18]. Meanwhile, the United States is also one of the counties with largest electricity consumption per capita in the world. Second, Japan, owning similar culture with China, is located in East Asia. As a developed country, its electricity consumption per capita is much higher than the world average s. Furthermore, Japanese has almost the same national traditions and living habits with Chinese. Third, France, as a member of the European 8

15 Union, has the same population density with China. As discussed above, it is a developed country with highly renewable energy generation. Figure 6. Electricity demand of the US from 1975 to 2016 [18] The peak of Chinese electricity consumption can be inferred from the industrial level or other aspects. However, compared with other methods, using electricity consumption per capita as basic value is more direct. From Table 5, the difference of electricity consumption per capita is not only between developed countries and developing countries, but also between developed countries themselves. It can be caused by development level, geographical and climatic conditions and concept of using electricity. Considering all above conditions, 8000 kwh per year, higher than Japanese and French but much lower than American, is assumed as the electricity consumption per capita in this report, because compared with geographical condition, geographical and climatic conditions and concept of using electricity are more important to determine the electricity demand of a country. Since the maximum value of electricity has been set up, so as to compute the time to reach the peak, the growth rate should also be estimated. From the behavior of above three counties before them arriving peak of electricity demand, growth rate of Chinese electricity demand can be assumed to go through three stages. Firstly, based on current average growth rate, 4.5 % from 2011 to 2016, Chinese electricity demand will increase in a relatively high speed, since Chinese economy growth and development are still on a high level [15]. Secondly, referring the behavior of growth rate of the US before the peak form 1985 to 2005, their growth rate is about 2.6 %. Thus, at second stage, the growth rate is assumed to gradually decrease from 3 % to 2 % in China. Finally, the third stage is after the peak. Considering Japanese growth rate behaviors in this stage, the electricity demand per capita is proportional to the Japanese population. Also, it is reported that, Chinese 9

16 population will increase from 1.38 billion people in 2016 to the maximum of 1.42 billion people in 2028 [19]. After that, the population of China will began negative growth. As shown in Table 6, the population of Japan is gradually decreased from 2010 to Table 6. Population and its growth rate of Japan from 2010 to 2017 [20]. Year Population (million) Growth rate Year Population (million) Growth rate The calculation of future electricity demand is shown in Appendix 1 and the results are shown in Table 7. Table 7. Future electricity demand from 2016 to 2040 Year Demand (PWh) Demand per capita (MWh) Year Demand (PWh) Demand per capita (MWh) Year Demand (PWh) Demand per capita (MWh) Year Demand (PWh) Demand per capita (MWh) Year Demand (PWh) Demand per capita (MWh) As shown in Table 7, the peak of electricity demand will be reached in 2035 and the demand is 11.3 PWh per year. 10

17 2.2 Nuclear power Actually, the development of nuclear power station in China has had a long history. Since the fifties of last century, China has begun to develop nuclear industry. After that, the first nuclear power plant of China was started to construct in 1985 and finished in After years of development, Chinese nuclear power is growing steadily. Up to now, 30 nuclear power plants have been built and 25 is under construction or on the plan [21]. The specific data of those nuclear power plants in China is shown in Table 8 and Table 9. Table 8. Installed nuclear power station in China until 2016 [21] Number Name Capacity (MW) Start year Completion year 1 Taishan 1# Taishan 2# Taishan 3# Taishan 4# Taishan 5# Taishan 6# Taishan 7# Dayawan 1# Dayawan 2# Aoling 1# Aoling 2# Aoling 3# Aoling 4# Tianwan 1# Tianwan 2# Hongyanhe 1# Hongyanhe 1# Ningde 1# Ningde 2# Yangjiang 1# Fuqing 1# Fangjiashan 1# Fangjiashan 2# Yangjiang 2# Ningde 3# Hongyanhe 3# Fuqing 2# Changjiang 1# Yangjiang 3#

18 30 Fangchengang 1# total Table 9. Constructing and planning nuclear power station in China until 2016 [21] Number Name Capacity (MW) Start year 1 Hongyanhe 4# Ningde 4# Fuqing 3# Fuqing 4# Yangjiang 4# Yangjiang 5# Yangjiang 6# Sanmen 1# Sanmen 2# Taishan 1# Taishan 2# Haiyang 1# Haiyang 2# Tianwan 3# Tianwan 4# Changjiang 2# Fangchengang 2# Shidao Hongyanhe 5# Fuqing 5# Hongyanhe 6# Fuqing 6# Fangchengang 3# Fangchengang 4# Tianwan 5# total Until 2015, installed capacity of nuclear power plant was GW and electricity production from nuclear power was GWh per year [15], covering approximately 3 % of total demand. In contrast, France is one of the most developed countries in nuclear power field. Although some western developed countries have started to close and stop to build nuclear power plants, nuclear power plants are still the best solution to replace thermal power plants in China. Therefore, there is still a huge space of development for nuclear power in China. 12

19 Compared with thermal power, nuclear power is a clean renewable energy source without any GHG emission. From the Chinese 13 th Five-Year Plan, Chinese government puts the development of nuclear power in a very important position. During 13 th Five-Year Plan period, the government plans to build at least five-1200 kw nuclear power plants each year [22]. By 2020, the nuclear power generation will reach 5 % of the total electricity demand and further to 8 %-10 % by 2030 [23]. As a matter of fact, Chinese new nuclear technology, called Hualong One, with independent intellectual property rights, is still not a mature technology. It will take at least three years before the technology put into commercial application. Thus there won t be new plan of construction of nuclear power station in the next three years [22]. According to Table 8 and Table 9, the average construction time of nuclear power plant is about 6 years, and so far, the average new installed capacity of each nuclear power unit is approximately 1.2 GW. Assumed no new nuclear power plant will start to set up from 2016 to However, in order to achieve 13 th Five-Year Plan, 8 to 9 nuclear power plants per year will began to construct since Furthermore, the annual operating time is assumed to be 7000 hours and the operating factor is about 80 %, based on historical data of Chinese nuclear power station [15]. The calculation of future nuclear power production is shown in Appendix 1 and the results are shown in Table 10. Table 10. Electricity production of nuclear power from 2016 to 2040 in China Year Production (PWh) Proportion of total demand Year Production (PWh) Proportion Year Production (PWh) Proportion Year Production (PWh) Proportion Year Production (PWh) Proportion

20 2.3 Hydro power Hydro power is currently Chinese largest renewable energy and provides the largest power generation except the thermal power. China has abundant water resources, almost 1/6 of the total world's resources [24]. In 2009, the largest hydro power station, Three Gorges Dam, was constructed in China. Its capacity could satisfy the total demand of Shanghai city. Furthermore, hydropower station could not only generate power, but also control the flood and irrigate. It is totally GHG-free renewable energy station. It is reported that he total potential capacity of hydropower resources in China is about 600 GW, and the current capacity is about half of that [24]. In other words, the growth rate of hydro power station construction in China could still be very high. In additional, the development of hydropower can effectively reduce the burning of coal, oil and natural gas resources, both saving valuable petrochemical energy and protecting the natural environment. Figure 7 shows utilization of Chinese water resources before Figure 7. Utilization of Chinese water resources before 2013 As shown in China Statistical Yearbook 2016, with high-speed development of hydropower from 2005 to 2015, Chinese hydropower installed capacity reached 50 % of all potential [15]. Thus, another 10-year high-speed development period could be assumed. The annual installing capacity is assumed to equal 18 GW, average installed capacity from 2005 to After that, the annual installing capacity will drop to 8 GW, average installed capacity from 2000 to 2005, until the total installed capacity reaches 600 GW. The annual operating time is assumed to be 3300 hours and the 14

21 operating factor is about 38 %, based on historical data of Chinese hydro power station. The calculation of future hydro power production is shown in Appendix 1 and the result is shown in Table 11. Table 11. Electricity production form hydro power from 2016 to 2040 Year Production (PWh) Proportion of total demand Year Production (PWh) Proportion Year Production (PWh) Proportion Year Production (PWh) Proportion Year Production (PWh) Proportion Wind power In recent years, China has become one of the world's leading countries in the field of wind power. Chinese installed capacity of wind turbine is greater than any other country's installed capacity, and new wind power equipment is still in rapid growth. Geographically, China has a huge land, with the western plateau region and the eastern long coastline. Figure 8 shows the current wind speed map in China. Most of those green areas is suitable to set up wind turbine, including Qinghai-Tibet Plateau, located in southwest of China, Inner Mongolia grassland, located in northern of China, and the eastern coastal areas. Therefore, wind power resources are excellent in China. It is estimated that the capacity of offshore wind energy and onshore wind energy are 0.2 TW and 2.3 TW respectively [25]. Up to now, capacity of installed turbine is about 160 GW. As shown in China Statistical Yearbook 2016, from 2005 to 2015, construction of Chinese wind power capacity is in the initial stage [15]. Due to the small base value, 15

22 installed growth rate was maintained at a very high level, and then, with the increasing of the base value, the annual growth rate of installed capacity has gradually dropped to a relatively low level. Figure 8. Current wind speed map in China [27] However, an obvious disadvantage of wind power is that the electricity produced by wind turbine will damage power grid because wind power is an unsteady source. The rotation of turbine should match suitable wind speed. Otherwise, wind turbine cannot effectively generate electricity. Although, Germany, as a developed country, has achieved a great success in introducing wind power into the smart grid, China is much larger than Germany and the deployment of electricity would be more difficult [26].So, it is assumed that 30 GW of wind turbine, installed capacity in 2015 [15], will be installed every year in the future, until reach the maximum potential capacity. The annual operating time is assumed to be 1600 hours and the operating factor is about 18 %, based on historical data of Chinese wind power station [15]. Of course, progress of technology should be concerning in the production of wind electricity. The improvement of operation time is assumed as 1 % per year [28]. The calculation of future wind power production is shown in Appendix 1 and the result is shown in Table 12. Table 12. Electricity production and proportion of wind power from 2016 to Year Production (PWh) Proportion of total demand Year Production (PWh) Proportion Year

23 Production (PWh) Proportion Year Production (PWh) Proportion Year Production (PWh) Proportion Solar power Likewise, China, as a country with vast land and huge energy demand, is the world's largest solar thermal market. Since 2013, China's photovoltaic installation has been ahead of the world. It is reported that the total potential of solar energy in China is 920 GW [29]. And so far, the total installed capacity of Chinese solar equipment is about 77.4 GW in 2016 [15]. According to China Statistical Yearbook 2016, the behavior of growth rate of solar power is similar to that of wind power in China, and those two kinds of energy are in the same development stage. At the same time, solar energy has the similar disadvantage with wind power. Therefore, some assumptions about wind power generation can also be used in the solar power generation. It is assumed that the future annual installing capacity of solar power is 40 GW, by considering the installed capacity in 2015, until the total potential capacity has been reached. The annual operating time is assumed to be 1000 hours and the operating factor is about 11 %, based on historical data of Chinese solar power station [15]. Of course, progress of technology should be concerning in the production of solar electricity. The improvement of operation time is assumed as 1 % per year [30]. The calculation of future solar power production is shown in Appendix 1 and the results are shown in Table 13. Table 13. Electricity production and proportion of solar power from 2016 to Year Production (PWh) Proportion of total demand Year Production (PWh) Proportion Year

24 Production (PWh) Proportion Year Production (PWh) Proportion Year Production (PWh) Proportion Thermal power Thermal power generation, as Chinese major source of electricity, is the basis of Chinese economy. As it is shown in Table 3, the proportion of thermal power in China is about 75 % of total demand. Chinese main fossil fuel source is coal, thus, coal-fire energy covers 94 % of total thermal power, and the rest 6 % is natural gas fire energy [31]. Although the world is promoting low-carbon economy, thermal power is still rapid development in China. The reason is that demand of coal is decreasing because of recession of steel industry in China, which leads to price fall of coal, as well as decreasing the cost of coal fire energy station. Of course, this anomaly cannot exist for a long time, since the government has shut down a lot of constructions of thermal power plant. Also, coal fire energy equipments are based several technologies, including medium temperature and pressure technology, high temperature and pressure technology, super high pressure technology, subcritical technology, supercritical technology and ultra-supercritical technology [32] [10]. The main difference between those technologies is the effectiveness of electricity production. In other words, new technology could reduce the emission of GHG. The characteristic of those technologies is shown in Table 14. It is reported that Chinese thermal power installed capacity will reach a peak of TW in 2020 [34]. Table 14. Characteristics of several thermal power technologies [10] [33] [31] Technology Capacity per unit (MW) Efficiency Proportion of total installed capacity Carbon emission factor (kg CO 2 /GWh) Natural gas Medium temperature and pressure

25 High temperature and pressure Super high pressure Subcritical Supercritical Ultra-supercritical Ultra-supercritical Ultra-supercritical It is assumed that capacity of new constructing thermal power station will maintain at 50 GW per year, and all the technologies of those stations are using the latest thermal power technology [10]. Meanwhile, 50 GW old thermal power plants will be closed per year after 2020, in order to maintain the total installed capacity at approximately TW. Also, with progress of technology, the latest fire-coal power technology is divided into three stages [10]. Before 2020, efficiency of generator is assumed to be From 2020 to 2030, the efficiency will increase to 0.45 and after 2030, increasing to For simplifying calculation, natural gas thermal power maintained original installed capacity in 2015, about GW. Since production of thermal power could be adjusted by the demand, operation time is not considered in this report. The production of thermal power is equal to total demand minas all renewable energy electricity production. The calculation of future thermal power production is shown in Appendix 1 and the result is shown in Table 15. Table 15. Electricity production and proportion of thermal power from 2016 to Year Production (PWh) Proportion of total demand Year Production (PWh) Proportion Year Production (PWh) Proportion Year Production (PWh) Proportion Year Production (PWh) Proportion

26 As shown in Table 15, the peak of thermal energy production will be reached in 2035, however, the proportion of that is decreasing year by year from GHG emission from electricity production sector Combining all above results, the emission data is shown in Table 16 and Figure 9, as well as, the calculation, all needed data and assumption are shown in Appendix 1. Table 16. Carbon emission from electricity production from 2016 to 2040 Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons) ,1 4,9 4,7 Electricity 4,5 4,3 Electricity 4,1 3,9 3, Figure 9. Carbon emission from electricity production from 2016 to 2040 (Gtons) Emission from electricity production will reach the peak of 5.0 Gtons GHG in

27 3. Industry Industry, as a country's foundation, belongs to the secondary sector. Chinese industrialization has not been completed and still has a huge gap with developed countries. With the continuous development of industry, industrial carbon emission is another main source in China. The majority emission source in industrial sector is burning of coal, oil and natural gas in the plant. Meanwhile, the process of coal mining, cement production and lime production will emit extra GHG [35]. In order to simplify the writing, all sub-sectors of industry have been coded in Appendix 2. Also, as shown in Table 17, the growth rate of fossil fuel consumption in industry could assume to be proportional to that of industrial GDP. In additional, all of increased electricity production is assumed to apply in industry sector. And the predicted GDP is shown in Table 18. Table 17. Factor between growth rate of GDP and that of energy consumption [15] GDP (Trillion Yuan) Energy consumption (Ttons SCE*) * Standard Coal Equivalent Annual growth rate Factor 1.85 Table 18. Predicted annual growth rate of Chinese GDP from 2011 to 2050 [36] Year Total (%) Primary sector (%) Secondary sector (%) Tertiary sector (%) Emission from burning of fossil fuel Except the normal sub-sectors of industry, several sub-sectors growth rate will not obey the relation with growth rate of GDP, including S1, S3, S9, S14, S15, S16 and S24 [37]. Since those sub-sectors are under recession, the growth rate will be negative. The emission will be computed by consumption of different energy source and those 21

28 specific factors are shown in Table 19. The calculation is show in Appendix 3 and the result is shown in Table 20. Table 19. Emission factors of several energy sources [38] Source Emission factor (kg CO 2 /kg) Coal Coke Crude Gasoline Kerosene Diesel Fuel oil Natural gas kg CO 2 /m 3 Table 20. Emission from all sub-sectors from 2015 to 2040 Sector (Gtons) S S S S S S S S S S S S S S S S S S S S S S S S S S

29 S S S S S S S Total Emission from coal mining escape At present, it is reported that China produces over 3.5 Mtons coal in The greenhouse gases, produced by the coal mining process, is not only emissions from fossil fuel combustion, but also extra methane escaping from coal layer [35] [39]. At present, there are two methods, downhole mining and open pit mining, to extract coal from underground. Compared to open pit mining, widely used abroad, downhole mining will release more methane to atmosphere. The emission factor of both methods are shown in Table 21. As a matter of fact, 90 % of coal mining is downhole mining in China [40]. Thus, Chinese government is promoting this advanced technology. It is assumed that 0.5 % of total coal mining sector will change from downhole mining to open pit mining every year. Emissions are shown in the Table 22 and calculation is shown in Appendix 3. Table 21. Emission factor of two methods [39] Mining Emission factor ( tons CO2/ktons coal) Downhole Open pit Table 22. Emission from coal mining escape Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons)

30 3.3 Emission from cement production In China, the production of cement is about 1.48 Mtons in 2015 [15]. Unlike other industrial process, cement production will additional carbon dioxide because of decomposition of carbonate mines in the production process. The growth rate is assumed obey the relation with GDP. With reference to a specific cement plant in China, the emission factor of cement production life cycle is shown in Table 23. As emission from fossil fuel combustion and electricity have been considered in above part, only decomposition of carbonate and organic carbon from row material will be computed in this part. Based on that, the emission is shown in Table 24, and calculation is shown in Appendix 3. Table 23. Emission factor of cement production [41] Carbon source Factor (kg CO 2 /t cement) Decomposition of carbonate Organic carbon from row material 7.10 Combustion of fossil fuel Electricity Total Table 24. Extra emission from cement production Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons)

31 3.4 Emission from lime production There are 0.2 Mtons lime produced in 2015 in China [42]. Emission from lime production is similar to that form cement production. Thus, the additional carbon dioxide should be considered. The growth rate is assumed obey the relation with GDP. The emission characteristic of lime production life cycle is shown in Table 25. As emission from fossil fuel combustion has been considered in above part, only decomposition of carbonate will be computed in this part. Based on that, the emission is shown in Table 26, and calculation is shown in Appendix 3. Table 25. Emission factor of lime production [42] Carbon source Factor (kg CO 2 /tons lime) Decomposition of carbonate Combustion of fossil fuel Total Table 26. Extra emission from lime production Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons) GHG emission from industry sector Due to the increasing of electricity production, less fossil fuel will be combusted in industry. Therefore, replaced fossil fuel will be saved and GHG emission will decrease. Combining all above results, the emission data is shown in Table 27 and Figure 10, and the calculation is shown in Appendix 3. 25

32 Table 27. Total emission from industrial sector from 2016 to 2040 Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons) Industry 9,3 9,1 8,9 8,7 Industry 8,5 8, Figure 10. Total emission from industrial sector from 2016 to 2040 (Gtons) With all above assumption, there is no peak of emission in industry sector until

33 4. Agriculture In all over the world, agriculture is an important sector, involved in people's livelihood, and also, an important source of carbon emissions. China, as a large agricultural country, has 1.63 million square kilometers farmland [15]. The carbon emissions of agricultural are mainly from crop farming and livestock. And its main components are considered as nitrous oxide and methane without carbon dioxide, since release from respiration of animals and plants is usually not regarded in the context of GHG emissions. Meanwhile, the emission from burning of fossil fuels and biomass is included in this section. The emission of agriculture is shown in Table 28. Table 28. Emission from crops and livestock from 2001 to 2008 [43] Year Crop (thousand tons) Livestock (thousand tons) Carbon emission Ch 4 N 2 O Ch 4 N 2 O (Mtons) According to Table 28, there is little change of GHG emissions from Chinese crop farming and livestock over the years. Furthermore, agriculture, as primary sector, is assumed to obey the relation with GDP. 4.1 Emission from crop farming Crop farming includes the cultivation of various crops and its GHG emissions are from crops and fertilizer. As a country with 1.3 billion populations, it is difficult to decrease the amount of planting. Thus, in order to control GHG emission, optimizing application of fertilizer is a feasible path. Furthermore, both nitrogen fertilizer and compound fertilizer would release nitrous oxide. However, the GHG emission of nitrogen fertilizer is 8 times as big as that of compound fertilizer [43]. Therefore, the government is promoting compound fertilizer to reduce greenhouse gas emissions. There is 1663-square-kilometer farmland in China in 2015 [15]. It is assumed that the emission from crop and fertilizer are both proportional to the population of China and 27

34 due to the declining nitrogen fertilizer application, a decreasing factor would be added into calculation. The results are shown in Table 29 and calculation is shown in Appendix 4. Table 29. Emission from crops cultivation Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons) Year Emission (Gtons) Emission from livestock Livestock include pig, cattle, sheep, camel, rabbit, donkey, horse, mule and poultry [15]. According to China Statistical Yearbook 2016, only cattle, camel and poultry are increasing in past 5 years. Thus those three species is assumed to have a positive growth rate and the rest species will have a negative one. However, both of those two growth rate will gradually decease. The GHG emission is from livestock s digestion and excreta [43]. The emission factor of those livestock is shown in Table 30. The result is shown in Table 31 and calculation is shown in Appendix 4. Table 30. Emission factors of several livestock [43] Species Digestion (kg/livestock) Excretion (kg/livestock) CH 4 CH 4 N 2 O Cattle Horse Donkey Mule Camel Pig Sheep Rabbit Poultry