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The ever-increasing challenges related to water security and climate mitigation underscore the pressing need for forward-thinking systems planning tools to drive urban sustainability transitions. In this study, we propose a novel city-level multi-objective planning framework that explores the nexus between carbon trading and water management, with the aim of facilitating water-efficient urban industrial restructuring. The framework integrates cap-and-trade mechanisms into a two-layered optimization model, creating an integrated approach to optimizing carbon emissions and generating economic opportunities for improving water efficiency. To illustrate the potential application of this framework, we conducted a case study focusing on Dongguan City, a water-stressed industrial metropolis in southern China. The results illustrate potential synergies between water planning strategies and carbon trading schemes, which could be harnessed to enable targeted reductions in water usage and carbon emissions. Furthermore, our findings identify the textile, apparel, and paper products manufacturing industries as primary candidates for strategic production scale reduction, emphasizing the importance of sustained support for the development of the computer and electronic manufacturing sector as a catalyst for urban sustainability transitions. By pioneering this new nexus-based perspective, our study offers valuable insights into long-term strategic planning for a low-carbon and resource-efficient urban economy. • Synergizing carbon trading and water management within a novel integrated planning framework. • Implementing resource-efficiency-driven optimization for water- and carbon-intensive manufacturing sectors. • Gaining insights into the specific roles of key manufacturing sectors in water management and carbon trading. • Introducing carbon trading systems may help in promoting water-efficient industrial restructuring. [Display omitted] [ABSTRACT FROM AUTHOR]

• China LEAP model used to assess multi-sector decarbonization strategies to 2050. • Energy, CO 2 impacts of accelerated electrification and renewables are assessed. • 2025 CO 2 peak feasible under 4 strategies, peak levels vary from 10.2 to 10.7 GtCO 2. • Faster electrification's CO 2 impact depend on pace of power sector decarbonization. • Demand-side renewable has similar CO 2 reduction impact as power decarbonization. Energy efficiency has played an important role in helping China achieve its domestic and international energy and climate change mitigation targets, but more significant near-term actions to decarbonize are needed to help China and the world meet the Paris Agreement goals. Accelerating electrification and maximizing supply-side and demand-side renewable adoption are two recent strategies being considered in China, but few bottom-up modeling studies have evaluated the potential near-term impacts of these strategies across multiple sectors. To fill this research gap, we use a bottom-up national end-use model that integrates energy supply and demand systems and conduct scenario analysis to evaluate even lower CO 2 emissions strategies and subsequent pathways for China to go beyond cost-effective efficiency and fuel switching. We find that maximizing non-conventional electric and renewable technologies can help China peak its national CO 2 emissions as early as 2025, with significant additional CO 2 emission reductions on the order of 7 Gt CO 2 annually by 2050. Beyond potential CO 2 reductions from power sector decarbonization, significant potential lies in fossil fuel displaced by renewable heat in industry. These results suggest accelerating the utilization of non-conventional electric and renewable technologies present additional CO 2 reduction opportunities for China, but new policies and strategies are needed to change technology choices in the demand sectors. Managing the pace of electrification in tandem with the pace of decarbonization of the power sector will also be crucial to achieving CO 2 reductions from the power sector in a scenario of increased electrification. [ABSTRACT FROM AUTHOR]

Highlights • Spatiotemporal changes of central heating CO 2 emissions at city level are shown. • A high-resolution gridded inventory of heating-related CO 2 emissions is built. • The satellite nighttime light data is used to downscale the city level emissions. • Differences in CO 2 emissions between urban and non-urban areas are discussed. Abstract Energy consumption from central heating has rapidly increased in the cities of the North China Plain (NCP). The increasing use of natural gas in the central heating supply system may have altered the spatial and temporal patterns of CO 2 emissions from central heating, yet the quantitative impacts are poorly understood. Here we detect the spatio-temporal dynamics of CO 2 emissions of central heating from 2012 to 2016 at the prefectural-city level in the NCP region, by using the satellite NPP-VIIRS nighttime light data and a panel regression model to estimate CO 2 emissions on a 5 × 5 km2 grid. We find that despite a slight decrease (2%) in 2014 under the "Natural Gas Utilization Policy", CO 2 emissions continued to grow. Between 2012 and 2016, CO 2 emissions from central heating in the NCP increased from 106 to 121 Tg, although CO 2 emissions declined by 12% in Beijing due to the increasing contribution of natural gas boilers. The gridded CO 2 emissions map shows that over 2012–2016 coal burning is the main driving force of CO 2 emissions in both urban and non-urban regions, despite the increasing fraction of gas-based heating. Our results contribute to city-level policymaking on carbon reduction and climate change mitigation. The high-resolution gridded CO 2 emissions can also be applied in physical models to facilitate carbon cycle studies. [ABSTRACT FROM AUTHOR]

Highlights • 2050 primary energy use can be the same as in 2010 with a 7-fold increase in GDP. • Coal use can peak around 2020, then oil in 2033, and natural gas in 2045. • Non-fossil energy is 28% in 2030, higher than China's Paris Agreement goal of 20%. • Industry CO 2 emissions can peak ∼2020, buildings ∼2029, and transportation ∼2035. • CO 2 emissions can peak in 2025, earlier than China's Paris Agreement goal of 2030. Abstract As part of its Paris Agreement commitment, China pledged to peak carbon dioxide (CO 2) emissions around 2030, striving to peak earlier, and to increase the non-fossil share of primary energy to 20% by 2030. Yet by the end of 2017, China emitted 28% of the world's energy-related CO 2 emissions, 76% of which were from coal use. How China can reinvent its energy economy cost-effectively while still achieving its commitments was the focus of a three-year joint research project completed in September 2016. Overall, this analysis found that if China follows a pathway in which it aggressively adopts all cost-effective energy efficiency and CO 2 emission reduction technologies while also aggressively moving away from fossil fuels to renewable and other non-fossil resources, it is possible to not only meet its Paris Agreement Nationally Determined Contribution (NDC) commitments, but also to reduce its 2050 CO 2 emissions to a level that is 42% below the country's 2010 CO 2 emissions. While numerous barriers exist that will need to be addressed through effective policies and programs in order to realize these potential energy use and emissions reductions, there are also significant local environmental (e.g., air quality), national and global environmental (e.g., mitigation of climate change), human health, and other unquantified benefits that will be realized if this pathway is pursued in China. [ABSTRACT FROM AUTHOR]

Petroleum coke, a non-environmentally friendly energy source, is gradually replacing other power fuels in China’s industrial enterprises because of its price advantage. Petroleum coke has high emission factors and thus emits more greenhouse gases (GHGs) and air pollutants than even raw coal. This study first examines the rapid growth of petroleum coke consumption in China since 2010 by industry sector and region and then estimates the petroleum coke-related emissions. We conclude that the total consumption of petroleum coke increased by 18.9% from 2010 to 2016 and that the industry final consumption for burning in boilers increased dramatically (by 158.2%). Petroleum coke-related CO 2 emissions reached 28 million tonnes in 2016, whereas CH 4 and N 2 O emissions totaled 870 and 143 tonnes, respectively. The increased use of petroleum coke will increase the urgency for the development of climate change mitigation and emissions reduction measures in China. We propose several possible policy suggestions for petroleum coke management and emissions control, such as strongly restricting the production and import of high-sulphur petroleum coke, as well as burning petroleum coke to provide power; more power plants and industrial kiln stoves/boilers should be equipped with efficient decontamination systems; the development of advanced industrial processes and the clean utilization of petroleum coke should be encouraged. [ABSTRACT FROM AUTHOR]

The iron and steel industry plays an important role in mitigating global climate change. As the largest steel producer and consumer, China bears the primary responsibility for energy savings and CO 2 emission reduction in the iron and steel industry. In this study, taking China as the empirical context, we analyze the effectiveness of the following four strategies on the potential of energy savings and emission reduction: phasing out backward production capacity in accordance with the current major policies, adjusting the production structure to increase electric arc furnace steelmaking, promoting low-carbon technologies, and switching to clean fuels. Under the principle of cost minimization, the mitigation potential of different strategies until 2030 and the technological development paths for reducing energy and CO 2 emissions in China’s iron and steel industry are identified via an established National Energy Technology model. The results show that promoting low-carbon technologies is the most effective strategy for energy savings and emission reduction alongside cost minimization. Compared with existing policies, these strategies could lead to a cumulative reduction of 818.3 MtCO 2 (4.1%) during the period 2015–2030. Therefore, policy makers should provide financial or administrative support to promote the development of specific production and low-carbon technologies such as non-blast furnace iron-making and endless strip production. [ABSTRACT FROM AUTHOR]

Water consumption in thermoelectric and hydropower plants in China increased from 1.6 and 6.1 billion m 3 , respectively, to 3.8 and 14.6 billion m 3 from 2002 to 2010. Using the concept of virtual water, we attribute to different electricity users the total water consumption by the electric power sector. From 2002 to 2010, virtual water embodied in the final consumption of electricity (hereinafter referred to as VWEF) increased from 1.90 to 7.35 billion m 3 , whilst virtual water in electricity used by industries (hereinafter referred to as VWEI) increased from 5.82 to 11.13 billion m 3 . The inter-provincial virtual water trades as a result of spatial mismatch of electricity production and consumption are quantified. Nearly half (47.5% in 2010) of the physical water inputs into the power sector were virtually transferred across provincial boundaries in the form of virtual water embodied in the electricity produced, mainly from provinces in northeast, central and south China to those in east and north China. Until 2030, VWEF and VWEI are likely to increase from 5.27 and 14.89 billion m 3 to 7.19 and 20.33 billion m 3 , respectively. Climate change mitigation and water conservation measures in the power sector may help to relieve the regional pressures on water resources imposed by the power sector. [ABSTRACT FROM AUTHOR]

The industrial sector is a major source of China's major CO 2 emissions. In 2012, the emissions embedded in the final-use-induced intermediate CO 2 flows contributed to approximately 91.2% of the total emissions. Hence, controlling CO 2 emissions along supply chains could have a significant contribution in achieving the climate mitigation goal to which the Chinese government has been committed. In this study, we first extracted final-use-induced CO 2 transfer networks from input-output tables, and then applied the power-of-pull approach to the networks to identify the key sectors significantly affecting the CO 2 emissions of each targeted sector's supply chains. Our results showed that each sector itself has significant power of pulling their emissions. Energy and raw material providers have played an essential role in pulling other sectors' emissions in the past years. The results of all sectors can easily construct a network reflecting the system’s characteristics. And the power-of-pull approach could easily be integrated with the structural path analysis. Our proposed approach has the potential in helping policy making by offering a new perspective. [ABSTRACT FROM AUTHOR]

[Display omitted] • Global land-use impacts of China's bioenergy import schemes were explored. • Major sustainability concerns arise when relying on any single market for biomass import. • Economically optimized biomass import can partly mitigate sustainability tradeoffs. Most ambitious climate change mitigation pathways indicate multifold bioenergy expansion to support the energy transition, which may trigger increased biomass imports from major bioenergy-consuming regions. However, the potential global land-use change and sustainability trade-offs alongside the bioenergy trade remain poorly understood. Here, we apply the Global Biosphere Management Model (GLOBIOM) to investigate and compare the effects of different increasing bioenergy import strategies in line with the 1.5℃-compatible bioenergy demand in China, which is projected to represent 30% of global bioenergy consumption by the middle of the century. The results show that sourcing additional bioenergy from different world regions could pose heterogeneous impacts on the local and global land systems, with implications on food security, greenhouse gas emissions, and water and fertilizer demand. In the worst cases under strict trade settings, relying on biomass import may induce up to 25% of unmanaged forests converted to managed ones in the supplying regions, while in an open trade environment, increasing bioenergy imports would drastically change the trade flows of staple agricultural or forestry products, which would further bring secondary land-use changes in other world regions. Nevertheless, an economically optimized biomass import portfolio for China has the potential to reduce global overall sustainability trade-offs with food security and emission abatement. However, these benefits vary with indicator and time and are conditional on stricter land-use regulations. Our findings thus shed new light on the design of bioenergy trade strategies and the associated land-use regulations in individual countries in the era of deep decarbonization. [ABSTRACT FROM AUTHOR]

China’s commitment to the UNFCCC to peak its emissions by 2030, or sooner, signaled a long anticipated shift in China’s model of development with far reaching consequences. Cities in China, and particularly the residential sector in cities, will be charged with making significant reductions in emissions growth even as rates of urbanization continue to climb. Focusing on Beijing and Shanghai, this paper carries out a measures-based economic analysis of low carbon investment opportunities in the residential sector. Results find significant opportunity: between 2015 and 2030, BAU levels of CO 2 emissions could be reduced by 10.2% in Beijing and 6.8% in Shanghai with the adoption of economically attractive low carbon measures. While these headline results underline the case for low carbon investment in the residential sectors of these megacities in China, a closer analysis provides insights for understanding the economics of decarbonisation in cities more generally. [ABSTRACT FROM AUTHOR]

The so-called post-China countries (PC-16́s), distinguished by low wages and high economic growth, will replace China as the “world’s factory”. The aim of this paper is to assess the effect of these changes on global CO 2 emissions pathways. To achieve this, a counterfactual is proposed wherein China’s trade with the rest of the world is replaced by the PC-16’s trade in a global multiregional input–output context. The emissions savings realized by trade replacement are significant in those scenarios where the current pattern of trade is maintained (−13% on emissions traded and −3.5% on global emissions) and in scenarios where enterprises relocate their production directly or indirectly to the most environmentally efficient countries (ranging from −15.2% to −18.2% on emissions embodied in trade). Nevertheless, the potential savings drop considerably (ranging from −1.5% to −7.1%) if companies and host countries take advantage of cheaper, but more polluting means of production and do not internalize the externalities. Through changes in international trade, there is a possibility of reducing emissions, which have to be included in international, multilateral and bilateral agreements to mitigate climate change if we do not want to lose the opportunities these changes present. [ABSTRACT FROM AUTHOR]

• Three behaviors are responsible for 63–81% of indirect household carbon emissions. • Household carbon inequality larger than income inequality in poorer provinces. • On average, over 50% of a province's carbon accounts are self-production emissions. • Most CO 2 inflows/outflows of a province relate to 5 consuming/producing provinces. • Most CO 2 inflows/outflows of a province relate to 3 local/non-local sectors. The design of "fairness" and "justice" climate policies for controlling indirect household carbon emissions (IHCEs) requires joint efforts from the demand side and supply side. On the demand side, this study constructs behavior-specific IHCEs inventory for different household groups (differed by income level) in different regions to identify high-emitting households and corresponding high-emitting consumption behaviors. On the supply side, the "Carbon Account" is set up for different regions regarding various household consumption behaviors to screen all potential emitting-related stakeholders in the entire demand–supply chains. Using 25 Chinese provinces as study cases, the findings indicate that carbon inequalities across household groups are greater than income inequalities in poorer provinces, whereas the opposite is true in richer provinces. For most high emitting households (most were middle-high- and high-income households) in 25 provinces, Food & Beverage, Housing, and Durable goods are the top 3 carbon-intensive consumption behaviors, together accounting for 64–81% (72% on average) of total IHCEs. For the three carbon-intensive behaviors, the province-level carbon account analysis shows that a province's self-production emissions (local consumption, local emissions) took up an average of 52%, 70%, and 47% of its carbon accounts. An average of 83%, 80%, and 79% of net carbon transfer-in of a province (non-local consumption, local emissions) sourced from its 5 major consuming provinces, while 76%, 81%, and 77% of transfer-out (local consumption, non-local emissions) of a province were outsourced to its 5 major producing provinces, respectively. Furthermore, according to the sector-level carbon accounts, an average of 75%, 89%, and 76% of the sector carbon transfer-in, and an average of 72%, 80%, and 79% of the sector carbon transfer-out of a province were emitted by three dominant local or non-local industrial sectors, respectively. This study could provide policy implications for local governments to take joint climate mitigation strategies between the demand-side and supply-side targeting high-emitting household consumption behaviors. [ABSTRACT FROM AUTHOR]

Urban form is increasingly being recognised by scientists for the potential role it might play in the coordination of sustainable urban development and the reduction of CO 2 emissions. However, despite increasing interest in the morphology of cities in climate change science, few quantitative estimates have been made of the effects of urban form on CO 2 emissions. The goal of this study is to quantify this relation, using panel data for China’s 30 provincial capital cities from 1990 to 2010. In order to meet this aim, we first selected a series of urban form indicators, which we quantified by applying spatial metrics to remotely sensed data. We then estimated CO 2 emission levels using a unified standard method recommended by the IPCC Guidelines, and subsequently performed a panel data analysis. The results of the study demonstrated a positive correlation between the growth of urban areas and CO 2 emission levels. Further, it was also found that increased “urban continuity” led to reductions in CO 2 emissions and that, conversely, increased “urban shape complexity” exerted a positive influence in relation to CO 2 emissions. The findings of this study indicate that measures to make existing cities in China more compact may in fact help to reduce levels of CO 2 emissions, just as increasing fragmentation or increased irregularity with respect to urban form may contribute to increased CO 2 emissions. If serious about achieving meaningful reductions in CO 2 emissions, decision makers and planners should take urban form into consideration when developing low-carbon cities in China. [ABSTRACT FROM AUTHOR]

[Display omitted] • A bi-level joint-probabilistic programming approach is developed. • It can handle leader–follower issues and joint-probabilistic constraints. • The proposed approach is applied to China's multi-regional energy system model. • The optimal schemes during 2021–2050 under three mitigation scenarios are obtained. • Results are helpful to achieve low-carbon goals in multi-regional energy system. Climate change mitigation and renewable resources utilization are becoming particularly urgent for energy system management. In this study, a bi-level joint-probabilistic programming (BJPP) method is developed for planning multi-regional energy system under different mitigation policies and uncertainties. BJPP can handle leader–follower issues in decision-making process as well as examine the risk of violating joint-probabilistic constraints. Based on the BJPP method, a China's multi-regional energy system (named as BJPP_CMES) model is formulated to provide optimal scheme for energy system planning of China over a long-term horizon (2021–2050) by synergistically minimizing carbon dioxide (CO 2) emission and system cost. A series of scenarios associated with different carbon capture and storage (CCS) levels and violation risks of energy-demand constraints are examined. Results reveal that: (i) the share of non-fossil energy in China's energy supply would keep increasing in 2021–2050, and the highest growth of the renewable supply would occur in Ningxia (rising 47.7%); (ii) Sichuan, Inner Mongolia, and Gansu would be the top three suppliers of renewable electricity; (iii) the CO 2 emission of China would reach a peak of [44.3, 54.8] billion tonnes during the period of 2026–2030; Shandong, Inner Mongolia, and Shanxi would be main contributors of CO 2 emission in the future; (iv) compared with the single-level model, the CO 2 emission from the BJPP_CMES model would reduce by [2.7, 5.7]%; (v) among developed regions, the individual probability level of Jiangsu-Zhejiang-Shanghai is the most significant parameter for both CO 2 emission and system cost. The findings are helpful for decision makers to optimize multi-regional energy system (MES) with a low-carbon and cost-effective manner, as well as to provide useful information for renewable energy utilization and regional sustainable development. [ABSTRACT FROM AUTHOR]

• Energy upgrade is promoted by interprovincial coordinating of economy and resource. • Energy upgrade is determined by change of farmers' preference for low-quality energy. • Energy upgrade can be promoted together in agriculture and rural life. Rural energy upgrade in developing countries is an essential part of the world climate mitigation work. To systematically promote rural energy upgrade, we took the case of China and used a spatiotemporal model to investigate the spatiotemporal characteristics of energy ladders in agriculture and rural life of developing countries. The proportion of clean energy consumption in agriculture showed an interprovincial competition effect, whereas the proportion of oil consumption in rural life showed a demonstration effect. Severe reliance on coal hinders energy upgrade. Urbanisation has improved the clean level of energy use in agriculture but does not significantly affect the in rural life. Technological progress has increased the proportion of clean energy consumption but has little impact on the proportion of oil and gas consumption. The abundance of coal resources has prompted the massive use of coal and coal-fired power. Energy-use habit promotes the use of all types of energy. Except for that of gas, the consumption of different types of energy in agriculture and rural life mutually promotes. In summary, the development of energy technologies should be established based on the regional resource endowment and economic development level. Also, subsidy principles for clean energy projects should be established based on the development level of the agriculture and residents' income. Rural energy upgrade is coordinated with urbanisation and the modernisation of the agriculture and rural life styles while paying attention to the mutual promotion between the agriculture and rural life. During the change of the energy-use habit under policy guidance, attention must be paid to interprovincial cooperation. Finally, a reasonable market mechanism should be established to promote energy upgrade. [ABSTRACT FROM AUTHOR]

• An integrated top-down and bottom-up modeling framework was developed. • Analyze low-carbon pathways for Chinese iron & steel industry towards carbon neutrality. • Both the supply-side and demand-side contributions to decarbonization are explored. • Energy-saving retrofitting technologies help short-term CO 2 emissions reduction. • Breakthrough technologies are crucial in achieving carbon neutrality. Iron and steel production in China contributes to 14% of China's total energy-related CO 2 emissions. Decarbonizing the iron and steel sector will therefore play an important role in achieving the goal of carbon neutrality. This study explored possible low-carbon transition pathways for China's iron and steel industry to achieve carbon neutrality by 2050. An integrated approach was developed that combined a computable general equilibrium model and a bottom-up technology-selection module. The results indicated that although energy-saving technologies can reduce CO 2 emissions in the short term, in the long term, adopting breakthrough technologies (e.g., carbon capture and storage (CCS) and hydrogen-based direct reduction (DR)), increasing the share of scrap-based electric arc furnace (EAF) steel production, and decarbonizing upstream energy-supply sectors will be crucial for climate change mitigation. Hydrogen-based DR could be an effective option for CO 2 emission reduction in scenarios where CCS is not available, with its share increasing to 23%–25% by 2050. System-wide cross-sector decarbonization can help achieve climate targets at lower costs through flexible technology combinations and avoid carbon leakage into upstream energy-supply sectors. [ABSTRACT FROM AUTHOR]

• Baseline scenarios are essential and important in forward-looking studies. • Carbon tax policy impacts are found to be highly diverse across baseline scenarios. • Output levels can change dramatically (e.g. −19% to −64% for power output in India). • Real GDP can also change significantly (e.g. −0.66% to 1.54% in China). • Baselines with honed renewable projections facilitates fewer economic trade-offs. As a result of statistical contingencies, research frequently employs aged databases to examine the impacts of energy and climate change policies in contemporary situations, or in forward timeframes out to 2050 or even 2100. These forward-looking studies require a base case scenario in order to assess the impacts of a policy. In this article, we hypothesise how a baseline is 'rolled forward', and specifically, how this process can materially alter the apparent performance of an energy or climate change policy. In the literature, we find a variety of methods are used to update databases and project forward base case scenarios, some which scale an entire economy to a general trend of growth, whereas others account for sectoral differences. We extend a global electricity-detailed model (GTAP-E-Power) to examine our hypothesis. We evaluate impacts of a world-wide carbon tax policy ($50/t of carbon dioxide equivalent) using three different baselines, with varying levels of specificity relating to macroeconomic projections and sectoral developments and constraints. Results show the impact on sectors and the overall economy in all countries are highly diverse when different baselines are used. For example, fossil-based power output in the United States declines between 36.7 and 65.5% while Real GDP in China declines between −0.66 and −1.54% for an identical policy, depending on which baseline methodology is used. Above all, we find that stronger development of renewable energy and technology in the baselines results in lower costs of a climate change mitigation policy. [ABSTRACT FROM AUTHOR]

• A multi-GCM ensemble simulation and optimization approach is developed. • The developed approach can effectively tackle multiple uncertainties. • The impact of climate change on energy-economy-carbon nexus system is investigated. • Renewable energy will gradually replace fossil fuel for mitigating climate change. • There is a tradeoff between carbon dioxide emission and system cost. Climate change mitigation by reducing carbon dioxide emission becomes one of the major challenges for energy systems. In this study, a multi-GCM ensemble simulation and optimization approach is developed for analyzing the impact of climate change on China's energy-economy-carbon nexus system under multiple uncertainties through integrating techniques of multiple global climate models, support-vector-regression, Monte Carlo simulation, and interval chance-constrained programming within a general framework. The developed approach can tackle multiple uncertainties existed in global climate models, random carbon dioxide emission and complex optimization process. Results disclose that (i) the national electricity demand would grow around 58.6% in the next 30 years under climate change; (ii) for climate change mitigation and sustainable development, fossil fuel would be gradually replaced by renewable energy (i.e. the share of fossil fuel to the total energy supply decreasing 22.5% and the share of electricity generated from renewable energy increasing 27.0% by 2050); (iii) compared to the peak value in 2030, carbon dioxide emission would reduce 15.1% by 2050, most reduction from coal-fired power generation; (iv) there is a tradeoff between carbon dioxide emission and system cost as p-level decreases from 0.15 to 0.01 (i.e. carbon dioxide emission can reduce 1.9% with 3.7% of raised system cost). It is desired for China to adjust its current energy supply structure for reducing carbon emission and seeking a low-carbon developmental path. The most effective way is to eliminate some small coal-fired units. A number of wind-power and solar-power projects are expected to be implemented due to their abundant potential markets. [ABSTRACT FROM AUTHOR]