Study On The Scenario Of Clean Energy Utilization In Cheng-Yu District And Its Effect On Carbon Dioxide And Air Pollutants Emissions

As the fourth pole of China’s economic growth,the Chengdu-Chongqing city group belong to the“beautiful China Pioneer Area”for the construction of clean and low-carbon development.At the same tiome,it also belongs to the key air pollution control zone defined by the“Air Pollution Prevention Action Plan”.Accelerating the replacement of clean energy and building a clean energy system are important starting points for Cheng-Yu District to control greenhouse gas emissions and improve its air quality,and it is also the key links for building a"Chengdu-Chongqing Economic Circle"and fulfilling the requirements of"Beautiful China".Taking the promotion of clean energy use and energy structure adjustment for controlling the carbon dioxide and main air pollutants(NO_x、VOC_s、CO、SO₂ and primary PM_2.5)emissions as a starting point,this study quantitatively evaluated the self-guarantee conditions of regional clean energy substitution from the aspect of the clean energy resource and production-supply capacity of Cheng-Yu District initially,and identified the potential and orientation of clean energy substitution aiming at the time evolution and industry distribution of energy consumption and structure.Then,based on the reference scenario（BAU）,with 2017 and 2035 as the base year and target year respectively,three staged and differentiated clean energy utilization scenarios（mitigation scenario（MS）,policy scenario（PS）and radical scenario（RS））were designed after comprehensive consideration of the key factors affecting the future transformation of the energy structure into a clean type of Cheng-Yu District.At last,a localized LEAP-Chengyu model was constructed to account the energy-relative CO₂ and atmospheric pollutants under scenarios.According to the accounting results and combining with Logarithmic Mean Divisia Index I（LMDI I）,the differences and significances of the energy conversion,energy consumption and emissions of Cheng-Yu District under different scenarios were discussed.The main conclusions are as follows:（1）A systematic study of energy resource-production capacity-consumption structure showed that the energy resources in Cheng-Yu District presented a"lean coal,less oil,rich gas,and abundant water"pattern.By the end of 2016,natural gas reserves and hydropower technology exploitable proportions in Cheng-Yu District accounted for29.28%and 27.20%of national proportion respectively,and the clean energy resources conditions were superior.The energy output structure of Cheng-Yu District is continuously optimized year by year and have advantages in clean energy（natural gas,hydropower,etc.）output.In 2017,the output of natural gas and hydropower were 54.713and 42.705 million tce respectively,accounting for 30.4%and 19.0%of the domestic total output,which can provide resources and capacity guarantee for the future development of clean energy and the energy structure improvement.Although the energy consumption structure in Cheng-Yu District is continuously optimized and at a good level nationwide,coal fuel consumption still accounts for 44.6%of the total energy consumption and it still presents a consumption pattern that is dominated by coal and supplemented by clean energy up to 2017.Among them,industrial and transportation energy consumption are relatively high with non-clean energy accounts for a relatively large proportion,which are key industries for clean energy substitution.（2）The scenario analysis of energy consumption results indicated that under the MS and PS scenarios,the future energy consumption of Cheng-Yu District will further increase from 207.7 Mtce of the base year to 349.2 Mtce and 281.3Mtce of 2035 with average annual growth rate of 2.9%and 1.7%,respectively,which with energy saving rates of 41.3%and 52.7%compared with the BAU scenario,respectively.If industrial structure adjustment and energy efficiency improvement measures in various departments are adopted more vigorously than the existing policies,the total regional energy consumption under the RS scenario will be expected to reach a peak of 234.9 Mtce in2030,and then slowly drop to 229.3 Mtce in 2035,and the energy saving rate will be61.4%compared with the BAU scenario.In the future,industry will still dominate energy consumption in Cheng-Yu District,and it will still account for 48.5%of total energy consumption in 2035 even in the RS scenario with the greatest energy conservation.In addition,the energy consumption of the road transportation,life and service sectors has increased rapidly,and the proportion of total energy consumption has gradually increased in the region.（3）Scenario analysis results of CO₂ and air pollutant emissions presented that promoting the clean energy utilization and accelerating the transformation of the energy consumption structure to cleanliness has a significant inhibitory effect on the future growth of energy-related CO₂and air pollution emissions in the region.Compared with Bau scenario,CO₂,NO_x,VOC_s,CO,SO₂ and primary PM_2.5 emissions in MS,PS and RS scenarios are all significantly reduced,but the emissions of CO₂,NO_x,VOC_s,CO and SO₂ in MS scenario will further increase,and only primary PM_2.5 emissions will continue to decline.CO₂,NO_x and VOC_semissions in PS scenario will continue to rise,CO will peak in 2034,and only SO₂ and primary PM_2.5 emissions will continue to decline.If more radical energy structure transformation measures are taken than the existing policies,the emissions of CO₂,NO_x,VOC_s and CO under the RS scenario are expected to peak around2025,and the emissions of SO₂and primary PM_2.5 will continue to decline during the scenario.（4）The emission results of different sectors under different scenarios showed that the industrial CO₂ emissions accounted for 64.1%of the total emissions in 2017,and it still accounted for more than 50%under MS,PS and RS scenarios by 2035.Therefore,industry is the main source of energy-related CO₂ emissions,which has significant influence on the peak time and post peak trend of energy-related CO₂ emissions in Cheng-Yu District in the future.As of 2035,road transportation is the largest source of regional energy-related air pollutant emissions under different scenarios.Even under the RS scenario with the largest emission reduction efforts,the emissions of NO_x,VOC_s,CO,SO₂ and primary PM_2.5 from road transportation still account for 54.1%,50.0%,92.1%,37.4%and 46.3%of the total emissions respectively.The road transportation becomes the key sector for regional control of air pollutant emissions.（5）The decomposition results of emission drivers revealed that:the improvement of energy consumption level of industrial sector and the clean energy substitution of coal and heavy oil boiler（kiln）will contribute 294.4 Tg CO₂,597.3 Gg NO_x,200.2 Gg VOC_s,322.3 Gg CO,105.0 Gg SO₂ and 12.6 Gg primary PM_2.5 emission reduction from 2017to 2035,which completely offset the emission increment driven by activity level growth.What’s more,the contribution to CO₂,NO_x,VOC_s and SO₂ emission reduction under RS scenario is the largest.The emission reduction of CO₂ and air pollutants driven by the improvement of energy consumption per unit turnover and the proportion of clean energy vehicles in road transportation can only partially offset the increase of emissions caused by the increase of freight and passenger traffic turnover,which has the largest negative effect on emission reduction under RS scenario.The clean energy substitution of bulk coal and biomass fuel in the living sector contributed 320.5 Gg CO and 27.2 Gg primary PM_2.5 emission reduction,which completely offset the emission increment driven by the expansion of population scale and improvement of living standard,and made the largest contribution to the emission reduction of CO and primary PM_2.5under the RS scenario.