Rolling Decision Model of Thermal Power Retrofit and Generation Expansion Planning Considering Carbon Emissions and Power Balance Risk

With the increasing urgency of the carbon emission reduction task,the generation expansion planning process needs to add carbon emission risk constraints,in addition to considering the level of power adequacy.However,methods for quantifying and assessing carbon emissions and operational risks are lacking.It results in excessive carbon emissions and frequent load-shedding on some days,although meeting annual carbon emission reduction targets.First,in response to the above problems,carbon emission and power balance risk assessment indicators and assessment methods,were proposed to quantify electricity abundance and carbon emission risk level of power planning scenarios,considering power supply regulation and renewable energy fluctuation characteristics.Secondly,building on traditional two-tier models for low-carbon power planning,including investment decisions and operational simulations,considering carbon emissions and power balance risks in lower-tier operational simulations,a two-tier rolling model for thermal power retrofit and generation expansion planning was established.The model includes an investment tier and operation assessment tier and makes year-by-year decisions on the number of thermal power units to be retrofitted and the type and capacity of units to be commissioned.Finally,the rationality and validity of the model were verified through an example analysis,a small-scale power supply system in a certain region is taken as an example.The model can significantly reduce the number of days of carbon emissions risk and ensure that the power balance risk is within the safe limit.

Effect of Photovoltaic Power Generation on Carbon Dioxide Emission Reduction under Double Carbon Background

Increasing the efficiency and proportion of photovoltaic power generation installations is one of the best ways to reduce both CO_(2) emissions and reliance on fossil-fuel-based power supplies.Solar energy is a clean and renewable power source with excellent potential for further development and utilization.In 2021,the global solar installed capacity was about 749.7 GW.Establishing correlations between solar power generation,standard coal equivalent,carbon sinks,and green sinks is crucial.However,there have been few reports about correlations between the efficiency of tracking solar photovoltaic panels and the above parameters.This paper calculates the increased power generation achievable through the use of tracking photovoltaic panels compared with traditional fixed panels and establishes relationships between power generation,standard coal equivalent,and carbon sinks,providing a basis for attempts to reduce reliance on carbon-based fuels.The calculations show that power generation efficiency can be improved by about 26.12%by enabling solar panels to track the sun's rays during the day and from season to season.Through the use of this improved technology,global CO_(2) emissions can be reduced by 183.63 Mt,and the standard coal equivalent can be reduced by 73.67 Mt yearly.Carbon capture is worth approximately EUR 15.48 billion,and carbon accounting analysis plays a vital role in carbon trading.

A Distributed Computing Algorithm for Electricity Carbon Emission Flow and Carbon Emission Intensity

The calculation of the indirect carbon emis-sion is essential for power system policy making,carbon market development,and power grid planning.The em-bedded carbon emissions of the electricity system are commonly calculated by carbon emission flow theory.However,the calculation procedure is time-consuming,especially for a country with 500-1000 thousand nodes,making it challenging to obtain nationwide carbon emis-sions intensity precisely.Additionally,the calculation procedure requires to gather all the grid data with high classified levels from different power grid companies,which can prevent data sharing and cooperation among different companies.This paper proposes a distributed computing algorithm for indirect carbon emission that can reduce the time consumption and provide privacy protection.The core idea is to utilize the sparsity of the nodes’flow matrix of the nationwide grid to partition the computing procedure into parallel sub-procedures exe-cuted in multiple terminals.The flow and structure data of the regional grid are transformed irreversibly for pri-vacy protection,when transmitted between terminals.A 1-master-and-N-slave layout is adopted to verify the method.This algorithm is suitable for large grid compa-nies with headquarter and branches in provinces,such as the State Grid Corporation of China.

Development of a Low Carbon Economy in Wuxi City

The development of a Low Carbon Economy is a vital instrument to encounter climate change and take into account the growing challenges of an increasing urbanization in China. Wuxi City in East China’s Jiangsu Province is starting to implement a Low Carbon City Plan for safeguarding a sustainable development of the city until 2020 and beyond. This paper aims at estimating the impact of the Low Carbon City plan for Wuxi’s energy demand and CO2-emissions until 2050. Using an econometric energy supply and demand model to estimate and forecast the Wuxi energy and CO2-balance aggregates until 2050, it compares a scenario without specific Low Carbon City measures to reduce sectoral CO2-intensities to a Low Carbon scenario implementing these measures according to the Low Carbon City Plan until 2020 and beyond. The decomposition of the Kaya-identity reveals that the increase of per capita income has the largest impact on the growth of CO2-emissions and the decrease of energy intensity of Gross Value Added the largest impact on the reduction of CO2-emissions in Wuxi. A decrease of population and CO2-intensity of Primary energy supply only have average contributions. The decrease of energy intensity of Gross Value Added is due to energy efficiency gains in the single economic sectors, but to a large extent due to structural changes of the economy away from energy intensive sectors such as iron and steel, chemical industry or cement industry towards the energy extensive service sectors. A growing residential sector also reduces the industrial share of energy demand. Only following the assumed national trend with a shift from CO2-intensive industries to a CO2-extensive service economy, the Low Carbon goal of a 50% reduction of CO2-intensity of Gross Value Added compared to 2005 cannot be reached in Wuxi. Specific sectoral CO2 -intensity goals have to be successfully observed by the economic sectors in Wuxi, especially by the industry. The promotion of combined heat and power generation also has to contribute to the specific activities in Wuxi.

The accounting method and application of CO_2 emissions responsibility by the electricity sector at the provincial level in China

When accounting the CO_2 emissions responsibility of the electricity sector at the provincial level in China,it is of great significance to consider the scope of both producers' and the consumers' responsibility,since this will promote fairness in defining emission responsibility and enhance cooperation in emission reduction among provinces.This paper proposes a new method for calculating carbon emissions from the power sector at the provincial level based on the shared responsibility principle and taking into account interregional power exchange.This method can not only be used to account the emission responsibility shared by both the electricity production side and the consumption side,but it is also applicable for calculating the corresponding emission responsibility undertaken by those provinces with net electricity outflow and inflow.This method has been used to account for the carbon emissions responsibilities of the power sector at the provincial level in China since 2011.The empirical results indicate that compared with the production-based accounting method,the carbon emissions of major power-generation provinces in China calculated by the shared responsibility accounting method are reduced by at least 10%,but those of other power-consumption provinces are increased by 20% or more.Secondly,based on the principle of shared responsibility accounting,Inner Mongolia has the highest carbon emissions from the power sector while Hainan has the lowest.Thirdly,four provinces,including Inner Mongolia,Shanxi,Hubei and Anhui,have the highest carbon emissions from net electricity outflow- 14 million t in 2011,accounting for 74.42% of total carbon emissions from net electricity outflow in China.Six provinces,including Hebei,Beijing,Guangdong,Liaoning,Shandong,and Jiangsu,have the highest carbon emissions from net electricity inflow- 11 million t in 2011,accounting for 71.44% of total carbon emissions from net electricity inflow in China.Lastly,this paper has estimated the emission factors of electricity consumption at the provincial level,which can avoid repeated calculations when accounting the emission responsibility of power consumption terminals(e.g.construction,automobile manufacturing and other industries).In addition,these emission factors can also be used to account the emission responsibilities of provincial power grids.

The Economic and Environmental Impacts of Constructing Hydro Power Plants in Turkey:A Dynamic CGE Analysis(2004-2020)

Since Turkey’s economy and population is rapidly growing, Turkey mostly meets its energy demand from imported fossil sources due to the very limited indigenous oil and natural gas resources. However, Turkey has abundant renewable resources especially, hydro power potential to be used for generation of electricity. But only one-third of this significant economical potential could be used. This usage seems insufficient when compared with that of European countries. In order to analyze the potential long term impacts of the hydro power expanding shock on some macroeconomic variables of interest such as GDP, real consumption, real investment, exports, imports, trade balance, and carbon emissions, we developed TurGEM-D, a dynamic multisectoral general equilibrium model of the Turkish economy. Using TurGEM-D, we analyzed the impact of hydro power shock under policy scenario doubling hydro power generation. The simulation results show that doubling hydro power have slightly positive effects on macro indicators and carbon emissions for Turkish economy.

火电机组碳排放量及碳敏感性通用矩阵模型

为实现火电机组碳排放量的简便准确计量及掌握运行因素对机组碳排放强度的影响,在排放因子法技术上,参考传统q-γ-τ矩阵结构形式,根据求解火电机组碳排放量的需要,并掌握运行参数对发电碳排放强度的影响,建立了火电机组碳排放量及碳敏感性通用矩阵模型,确定了矩阵填写规则。采用热平衡法结合物料衡算法验证了模型的准确性,并与排放因子法核算结果对比;核算了某火电机组24 h的碳排放量,分析了排烟氧量、主蒸汽温度和压力波动时的发电碳排放强度的扰动量ΔM CO_(2)。结果表明:相较于排放因子法,本文所提模型缩短了碳排放量核算的时间跨度,且能提高碳排放量核算的精度;该机组24 h的碳排放量为5780.644 t;当排烟氧量降低0.1%时,ΔM CO_(2)为1.7726 g/(kW·h);当主蒸汽温度升高0.5 K时,ΔM CO_(2)为3.0206 g/(kW·h);当主蒸汽压力增加0.2 MPa时,ΔM CO_(2)为0.3788 g/(kW·h)。

2005—2035年全国电网碳排放因子的计算与预测

为解决全国电网碳排放因子数据更新滞后、计算方法不明确等问题,提出一种基于联合国政府间气候变化专门委员会(IPCC)碳核算法的全国电网碳排放因子计算方法。IPCC碳核算法涵盖了火力发电的25种能源。首先,计算2005—2022年全国电网碳排放因子;其次,通过对比全国电网碳排放因子的计算结果与官方公布数据,检验该方法的准确性,两者平均偏差仅为1.45%;最后,在基准情景、低碳情景和强化情景下,对2023—2035年的碳排放因子进行预测。2035年碳排放因子在3种情景中分别下降至0.5064,0.4807,0.4438 kg/(kW·h),电力低碳化水平持续提高。该计算方法具有较高的准确性,可动态反映我国电力结构的现状及变化趋势,为准确评估企业用电实际碳排放提供有力支撑。

中国新基建投资对碳排放强度的影响

为探究新基建投资与碳排放强度的关系,利用2010—2020年省级面板数据,建立双向固定效应模型,实证分析其影响效果和机制。研究发现:新基建投资对碳排放强度具有显著的抑制作用,能源消费强度在过程中具有正向调节作用;新基建投资对碳排放强度的作用效果存在区域异质性,新基建投资在东、中部地区都对碳排放强度具有显著的抑制作用,且在高综合算力地区,新基建投资对碳排放强度的抑制作用更为显著。

计及碳流的工业企业能源系统运行策略分析

为实现对工业企业能源系统中碳流轨迹的精确追踪,并制定有效的降碳运行策略,本文采用考虑网损的极坐标下的牛顿一拉夫逊迭代法,建立潮流稳态模型,用于分析系统中各节点和支路的有功潮流状态,以及网络损耗对系统性能的影响。此外,通过回归分析法对历史能耗数据进行建模,确定了燃煤发电机组的碳排放强度向量。进一步,建立了一个系统碳流分析模型,利用碳流与系统潮流的依赖关系,分析了各支路、负荷以及网损的碳流率,以及各个节点的碳势。为了实证所提方法的有效性,采用IEEE14节点系统为某工业企业构建了一个5机14节点的需求响应模型。通过仿真分析,研究了企业各用能环节的碳排放强度,实现了碳流的精确追踪。最后,为了优化工业企业能源系统的运行策略,采取了安装碳捕集装置和实施就地无功补偿两种措施,并通过模拟实验验证了这些措施降低系统碳排放的有效性。

考虑碳减排的火电机组煤耗基准值研究

燃煤机组作为新型电力系统的基础和压舱石,其高效经济运行是平稳达成“双碳”目标可行技术路径中的重要一环。基于机组历史运行数据建立稳态数据库和进行工况划分,采用灰色关联度分析方法,提取能效特征指标,并基于k-means聚类算法确定机组能效特征基准值,导入到计算模型获得机组供电煤耗最优基准值。最后,通过该方法获取一1 000 MW机组典型工况下的能效特征基准值,计算机组供电煤耗最优基准值,并以碳排放效益评估分析机组低碳运行的经济性,验证了该方法实际应用的可靠性。

从碳市场看燃煤机组生产方式的转变方向

“双碳”目标下,燃煤机组生产方式的转变势在必行。以全国碳市场及M企业近3年的碳排放数据为例,搭建了1个模拟碳排放逐年递减的数学模型,对M企业的生产方式进行了模拟,分析其经营结果。并以此为依据提出同类型燃煤机组生产方式的转变方向,分别为:纯凝运行方式向具备一定灵活性的供热运行方式转变,以及以“热电联产”运行方式在电力现货市场中获得对应生产优势,分别从生产与经营方面满足碳市场的严苛要求。

Evolving carbon dioxide emission rate intensities of coal-fired power plant on U.S. electricity operating systems

For many years, coal-fired power plant generation comprised the largest share of electricity in the U.S.power sector. While natural gas plants now constitute a greater portion of the total, coal is projected to remain a shrinking but significant component of U.S. electricity production. Natural gas-fired technologies are dispatchable and versatile generation sources, but the recent and anticipated growth of wind and solar technologies will add nondispatchable, intermittent power generation sources to U.S.electricity grids. Numerous emissions-related benefits arise from the deployment of these technologies, but they must coexist with coal plants, many of which run most efficiently under baseload operating procedures. Historical monthly emissions data has been analyzed on a sample of coal plants to show how modified coal operations have affected plant emission rates, as measured by carbon dioxide emitted per unit of electricity output. Statistically significant correlations between plant capacity factors and emission rate intensity have been observed by the majority of the sample, showing a worsening under more sporadic operations. Since nearly all of the coal plants in the sample are generating less electricity, determining the emission impact of operational decisions will assist policymakers as they seek to minimize total system emissions without severe disruptions to electricity cost and service reliability.

Assessment of Sustainable Energy Strategy with Long-Term Global Energy Model Incorporating Nuclear Fuel Cycle

This paper investigates long-term energy strategy compatible with significant reduction of world carbon dioxide （CO2） emissions, employing a long-term global energy model, Dynamic New Earth 21 （called DNE21）. The model seeks the optimal energy mix from 2000 to 2100 that minimizes the world total energy system cost under various kinds of energy and technological constraints, such as energy resource constraints, energy supply and demand balance constraints, and CO2 emissions constraints. This paper discusses the results of primary energy supply, power generation mix, CO2 emission, CCS （carbon capture and storage） and total system costs for six regions including world as a whole. To evaluate viable pathways forward for implementation of sustainable energy strategies, nuclear power generation is a viable source of clean and green energy to mitigate the CO2 emissions. Present research shows simulation results in two cases consisting of no CO2 regulation case （base case） and CO2 REG case （regulation case） which halves the world CO2 emissions by the year 2050. Main findings of this research describe that renewable and nuclear power generation will contribute significantly to mitigate the CO2 emission worldwide.

支撑电力系统全环节碳流追踪的节点导纳矩阵算法研究

为助力电力系统低碳化改革,电力系统碳计量应在测量发电侧直接碳排放的基础上,将碳排放责任从发电侧扩展至负荷侧和线路侧,得到电力系统全环节碳排放分摊责任。该文提出一种利用节点导纳矩阵运算实现碳流追踪的解析算法。结合潮流与碳流的换算关系,经矩阵运算得到电源、负荷及线路网损三者之间碳排放量分布关系的解析表达式。通过IEEE 30节点系统算例及与其他算法的对比分析,验证碳流追踪模型的正确性。此外,比较发电侧、负荷侧及线路侧计量方式下的节点和线路碳排放量,以及引入可再生能源及碳捕集与封存技术后系统全环节碳排放量的分布变化,并针对影响碳减排比例的因素展开分析,为后续碳排放责任分摊及系统低碳改造提供数据支持。

330 MW燃煤锅炉耦合ORC发电系统经济性分析

有机兰金循环(ORC)在锅炉烟气余热回收中具有一定的优势。针对某330 MW燃煤锅炉设计一套供厂用电的ORC烟气余热发电系统,计算厂用电率、供电热效率、供电煤耗率、供电碳排放强度及投资回收期,分析锅炉耦合ORC发电系统后机组的经济性。结果表明:采用锅炉耦合ORC发电系统后,厂用电率平均降低0.18个百分点,供电热效率平均增加0.07个百分点,供电煤耗率平均降低0.7 g/(kW·h),供电碳排放强度平均降低1.52 g/(kW·h),投资回收期为7.04 a。锅炉耦合ORC烟气余热发电系统具有一定经济性。

基于FCI-公平性的电力系统负荷侧碳排放责任分摊研究

电力系统碳排放责任的合理分摊,有助于准确判断重点减排区域,对促进各区域之间的减排合作和经济协同发展具有重要意义。为了确保电力系统碳排放责任分摊的合理性和公平性,在应用节点碳迹强度(Footprint Carbon Intensity,FCI)分摊方法完成负荷侧碳排放责任的首次分摊的基础上,创新性地引入适用于电力系统的“公平性区间”概念,构建了针对负荷侧的碳排放责任分摊公平性区间,完成了以满意度和满意度标准差为评估标准,基于区间中位数的分摊结果调整,在标准PJM-5节点系统算例中得到了很好的应用。对比原始的FCI分摊结果,考虑公平性的分摊方案更为公平、合理,符合行业的发展需求,具有广阔的应用前景。

绿色信贷对企业碳排放的影响--以发电企业为例

绿色信贷政策作为一项引领中国走向绿色发展的重要政策,是碳排放的重要影响因素。因此,本文以中国2012—2021年沪深A股上市发电企业为样本,研究绿色信贷对发电企业碳排放的影响,并深入探讨企业碳排放强度是否会影响绿色信贷政策效果。研究结果发现:绿色信贷会显著减少发电企业的碳排放,同时,在高碳排放强度下,发电企业的碳排放会受到更加显著的抑制效果。进而,本文提出以下建议:政府应提高对发电企业进行绿色发电的支持力度,根据发电企业自身状况优化资源配置。

Role of CCUS in carbon neutral power system

Achieving carbon neutrality by 2060 is an ambitious goal to promote the green transition of economy and society in China.Highly relying on coal and contributing nearly half of CO_(2) emission,power industry is the key area for reaching carbon-neutral goal.On basis of carbon balance,a criterial equation of carbon neutral for power system is provided.By means of the equation,the different effects of three technical approaches to achieve carbon neutrality,including energy efficiency improvement,shifting energy structure and CO_(2) capture,utilization and storage(CCUS)technology,had been evaluated.The results indicate that building a carbon-neutral power system requires comprehensive coordination between energy efficiency,renewable energy and CCUS technology.In particular,the unique role of CCUS in achieving carbon neutral target was investigated.For any power systems with fossil energy input,CCUS and negative emission technologies is indispensable to reach carbon neutrality.However,rather high energy consumption and costs is the critical gas deterring the large scale deployment of CCUS.Considering the specific conditions of China’s power industry,before the time window between 2030 and 2040 being closed,CCUS would either be ready for large scale deployment by reducing energy consumption and costs,or be phased out along with the most coal power plants.Conclusively,carbon neutral scenario will give CCUS the last chance to decarbonize the fossil fuel,which has great significance for China.

电力系统碳排放流的计算方法初探

电力系统碳排放流分析的理念为低碳电力带来了新的研究方向。根据潮流计算的结果准确而系统地求解电力系统中碳排放流的分布成为亟待解决的问题。在电力系统碳排放流分析理论的基础上,进一步分析了碳排放流和电力系统潮流计算之间的异同,以及电力系统碳排放流的影响因素、计算体系和计算思路;根据碳排放流求解的需要,定义了一些关键矩阵和向量;结合电力系统潮流计算方法与高等电力网络分析方法,在忽略网损的情况下,建立了电力系统碳排放流的基本计算方法,并通过算例系统验证了该方法的正确性。