Tian-Tian Feng

Integrating growing wind and solar generation while maintaining supply adequacy is a key challenge for sustainable power systems. However, the effects of different thermal retrofit pathways on renewable curtailment and modeled unserved energy remain unclear as renewable capacity expands. This study compares deep peak-shaving, fast-ramping, and combined retrofits using a PyPSA baseline and an 8760-h system dynamics simulation covering 31 Chinese provincial nodes. Doubling renewable capacity increases actual wind and solar generation by 51.4%, while the utilization rate falls from 91.4% to 69.2%. At baseline renewable capacity, the deep peak-shaving scenario S1 reduces annual curtailment by 25.0 TWh but produces 45.49 GWh of modeled unserved energy. S1 also reduces curtailment at renewable capacity multipliers of 1.50 and 2.00, whereas the fast-ramping scenario S2 has little effect on annual curtailment. At equal 50% retrofit coverage, the combined scenario S3 preserves S1’s curtailment benefit while nearly eliminating its supply shortfall. The expanded combined scenario S4, with 80% coverage, further reduces curtailment to 234.9 TWh at baseline renewable capacity. Considering curtailment and modeled unserved energy jointly, the combined retrofit provides the most favorable outcome among the equal-coverage pathways for supporting renewable integration while maintaining supply adequacy.

Under the constraints of the “dual carbon” goals, accurately depicting the full life cycle carbon footprint of green hydrogen and its derivatives and quantifying the potential for emission reduction is a prerequisite for hydrogen energy policy and investment decisions. This paper constructs a unified life cycle model, covering the entire process from “wind and solar power generation–electrolysis of water to producing hydrogen-synthesis of methanol/ammonia-terminal transportation”, and includes the manufacturing stage of key front-end equipment and the negative carbon effect of CO₂ capture within a single system boundary, and also presents an empirical analysis. The results show that the full life cycle carbon emissions of wind power hydrogen production and photovoltaic hydrogen production are 1.43 kgCO₂/kgH₂ and 3.17 kgCO₂/kgH₂, respectively, both lower than the 4.9 kg threshold for renewable hydrogen in China. Green hydrogen synthesis of methanol achieves a net negative emission of −0.83 kgCO₂/kgCH₃OH, and the emission of green hydrogen synthesis of ammonia is 0.57 kgCO₂/kgNH₃. At the same time, it is predicted that green hydrogen, green ammonia, and green methanol can contribute approximately 1766, 66.62, and 30 million tons of CO₂ emission reduction, respectively, by 2060, providing a quantitative basis for the large-scale layout and policy formulation of the hydrogen energy industry.

The carbon emission trading scheme (ETS), tradable green certificate (TGC) and green power trading (GPT) policies are vital for promoting energy transformation and carbon reduction under the dual carbon goals. However, the effects of and relationships among multiple policies urgently need to be studied. In this work, the panel data of 30 provinces in China from 2010 to 2023 are used. First, through the multiperiod difference-in-differences (DID) method, fixed effect models and mediating effect models, the carbon reduction effects of the pilot and national ETS policies, the renewable energy development effects of the TGC and GPT policies, and the multipolicy synergy effect are examined. A dual machine learning model is innovatively introduced to test the robustness of the results. Second, the slack-based measure–directional distance function–global Malmquist–Luenberger (SBM–DDF–GML) method is used to calculate the GTFP and investigate its transmission effect on policies. Finally, the impacts of the ETS, TGC and GPT policies on fossil fuel consumption are further analysed. The results indicate the following. (1) The pilot ETS policy reduces carbon emissions and carbon intensity, whereas the national ETS policy increases carbon emissions and carbon intensity in the short term. The TGC and GPT policies increase renewable energy generation and its proportion. (2) The synergy of the pilot ETS and GPT policies is the best for reducing carbon emissions and carbon intensity. The synergy among national ETS, TGC and GPT policies is optimal for developing renewable energy. In addition, there is redundancy between the TGC and GPT policies. (3) The pilot ETS policy inhibits GTFP, whereas the national ETS, TGC and GPT policies promote GTFP. The GTFP significantly reduces carbon emissions and carbon intensity and increases renewable energy generation and its proportion. (4) Both the pilot ETS and national ETS policies reduce the intensity of fossil fuel consumption. The GPT policy reduces the total level of fossil fuel consumption, whereas the TGC policy increases this level. In this work, innovative decarbonisation policies synergy pathways and insights into achieving green and low-carbon transitions in China and other developing countries are provided.

In the context of the global response to climate change and the active promotion of energy transformation, a number of low-carbon policies coupled with the development of synergies to help power system transformation is an important initiative. However, the insufficient articulation of the green power market, tradable green certificate (TGC) market, and carbon emission trading (CET) mechanism, and the ambiguous policy boundaries affect the trading decisions made by its market participants. Therefore, this paper systematically analyses the composition of the main players in the electricity-CET-TGC markets and their relationship with each other, and designs the synergistic mechanism of the electricity-CET-TGC markets, based on which, it constructs the optimal profit model of the thermal power plant operators, renewable energy manufacturers, power grid enterprises, power users and load aggregators under the electricity-CET-TGC markets synergy, and analyses the behavioural decision-making of the main players in the electricity-CET-TGC markets as well as the electric power system to optimise the trading strategy of each player. The results of the study show that: (1) The synergistic mechanism of electricity-CET-TGC markets can increase the proportion of green power grid-connected in the new type of power system. (2) In the selection of different environmental rights and benefits products, the direct participation of green power in the market-oriented trading is the main way, followed by applying for conversion of green power into China certified emission reduction (CCER). (3) The development of independent energy storage technology can produce greater economic and environmental benefits. This study provides policy support to promote the synergistic development of the electricity-CET-TGC markets and assist the low-carbon transformation of the power industry.

Under the global context of addressing climate change and actively promoting energy transition, green power has become increasingly vital in the energy structure due to its clean and sustainable advantages. However, the development of green power’s environmental value faces multiple challenges that hinder its marketization. This study first systematically analyzes the current status of developing the environmental value of green power and identifies existing issues. Second, it designs a green power environmental value mechanism and constructs a quantitative model from the perspective of coal-fired power carbon abatement costs, analyzing the emission reduction value of green power in replacing different types of coal-fired power generation. The results show the following: (1) When power generation types are not differentiated, the environmental value exhibits significant seasonal variations. (2) The environmental value for coal-fired units above 300 MW is lower than the overall average, while that of gas-fired units falls between coal-fired units and the average; the environmental value of generating units with a capacity of 300 MW or less is the lowest, followed by that of unconventional coal-fired units. (3) The environmental value calculated based on the marginal carbon abatement cost of coal-fired units, is slightly higher than the tradable green certificate (TGC) price. This study provides policy support for promoting the low-carbon transition of the power sector and facilitating the development of a green power trading market.

Amid global climate challenges, the European Union’s (EU) Carbon Border Adjustment Mechanism (CBAM) raises concerns over trade competitiveness and carbon leakage. This study integrates input–output theory and a recursively dynamic GTAP model, utilizing the 2020 Environmental Extended Input–Output Table and GTAP 11 database, to quantify direct and indirect carbon emissions across CBAM‐covered sectors. Innovatively incorporating dynamic updates and multidimensional scenarios (varying CBAM tax rates, Scope 1/2 emissions), we assess CBAM’s impacts on China–EU trade. The analysis reveals that CBAM has a negative impact on Chinese export commodity prices, export volumes, and trade conditions, with a higher tax rate leading to a more significant adverse effect on Chinese export trade. CBAM significantly reduces China’s export prices (−6.56 × 10 ⁻⁷ % under a $424/ton tax) and volumes (−12.5% decline), while marginally improving EU export prices (up to 1.14 × 10 ⁻⁵ %) but exacerbating global trade contraction (−50% for non‐EU regions). Sectoral heterogeneity highlights vulnerabilities in energy‐intensive industries. Findings underscore CBAM’s asymmetric trade effects, urging policy coordination to mitigate adverse global impacts.