IF 9 1区工程技术 Q1 ENERGY & FUELS

Energy

Pub Date : 2024-11-08 DOI: 10.1016/j.energy.2024.133742

Subha Mondal , Sudipta De

Combined flash binary geothermal cycle (CFBGC) is an efficient geothermal energy conversion technology. Natural gas (NG) is a preferred fuel in the current energy scenario. LNG gasification is a needed step for delivering NG among the end users. In the present study, a self-superheated single-flash geothermal steam cycle, a transcritical CO₂ power cycle and an LNG gasification unit are integrated into a CFBGC. This study shows that the LNG gasification rate and power output can be increased simultaneously by increasing the steam turbine inlet pressure. At a higher steam turbine inlet pressure, desirable steam quality (i.e., 0.9) at the steam turbine exit is maintained by implementing self superheating of the steam. It is observed that 15 °C DSH of steam enables the CFBGC to operate at a steam turbine inlet pressure that substantially enhances the output power without a noticeable increase in levelized electricity cost (LEC). The CFBGC operating at this condition yields 9.97 % higher power output compared to that of the CFBGC operating at steam turbine inlet pressure requiring no DSH of steam. As a geothermal-based power plant emits very low CO₂, the proposed energy system may emerge as a future sustainable energy option.

联合闪蒸二元地热循环（CFBGC）是一种高效的地热能转换技术。天然气（NG）是当前能源领域的首选燃料。液化天然气气化是向终端用户输送天然气的必要步骤。本研究将自过热单闪蒸地热蒸汽循环、跨临界二氧化碳发电循环和液化天然气气化装置集成到 CFBGC 中。研究表明，通过提高蒸汽轮机进口压力，可同时提高液化天然气气化率和功率输出。在较高的蒸汽轮机入口压力下，通过蒸汽的自过热，蒸汽轮机出口处可保持理想的蒸汽品质（即 0.9）。据观察，15 °C 的蒸汽自过热可使 CFBGC 在蒸汽轮机入口压力下运行，从而大幅提高输出功率，而不会明显增加平准化电力成本（LEC）。在此条件下运行的 CFBGC 与在蒸汽轮机进口压力下运行的 CFBGC 相比，输出功率高出 9.97%。由于地热发电厂的二氧化碳排放量极低，拟议的能源系统可能成为未来的可持续能源选择。

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引用次数: 0

Frequency security constraint in unit commitment with detailed frequency response behavior of wind turbines 机组承诺中的频率安全约束与风力涡轮机的详细频率响应行为

IF 9 1区工程技术 Q1 ENERGY & FUELS

Energy

Pub Date : 2024-11-08 DOI: 10.1016/j.energy.2024.133735

Jianshu Yu, Pei Yong, Juan Yu, Zhifang Yang

With the high penetration of wind turbines, the necessity of incorporating frequency security considerations into power system scheduling rises. Existing methods achieve the explicit modeling of frequency security constraints by simplifying the frequency response behavior of wind turbines. However, simplifications might lead to inaccuracy. To address this issue, this paper models the frequency response from wind turbines in detail and proposes a novel framework to construct the frequency security constraint for unit commitment (UC). First, the frequency security constraint is positioned at the segment that is effective for the dispatch decision instead of the whole boundary, which is unnecessary and complicated. Then, an analytical linear surrogate expression of the frequency security boundary is constructed through a data-driven approach. To ensure the accuracy of the surrogate constraint, a neighborhood sampling strategy is proposed to collect balanced samples. Furthermore, to reduce the linearization error of the surrogate constraints, supplementary constraints are added to restrict the width of the surrogate constraint. Finally, to address the modeling errors that may deviate from the frequency security requirements, a correction strategy is proposed. Case studies validate the proposed method and verify that it exceeds existing methods in the modeling accuracy of the power system frequency security.

随着风力涡轮机的高渗透率，将频率安全因素纳入电力系统调度的必要性日益增加。现有方法通过简化风力涡轮机的频率响应行为来实现频率安全约束的显式建模。然而，简化可能会导致不准确。为解决这一问题，本文对风力发电机的频率响应进行了详细建模，并提出了一种新的框架来构建机组承诺（UC）的频率安全约束。首先，频率安全约束被定位在对调度决策有效的区段，而不是整个边界，这既不必要又复杂。然后，通过数据驱动法构建频率安全边界的解析线性代用表达式。为确保代约束的准确性，提出了一种邻域采样策略来收集均衡样本。此外，为了减少代用约束的线性化误差，还增加了补充约束来限制代用约束的宽度。最后，针对可能偏离频率安全要求的建模误差，提出了一种修正策略。案例研究验证了所提出的方法，并证明该方法在电力系统频率安全建模精度方面超过了现有方法。

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引用次数: 0

Thermal-hydraulic characteristics of an earth air heat exchanger: An experimental analysis 土空气热交换器的热液压特性：实验分析

IF 9 1区工程技术 Q1 ENERGY & FUELS

Energy

Pub Date : 2024-11-08 DOI: 10.1016/j.energy.2024.133766

Emad M.S. El-Said

The pipe layout design has a great effect on the thermal-hydraulic characteristics of earth air heat exchanger (EAHE) systems. So, in the current study proposed four new buried pipe design configurations; low to high to low, high to low to high, spiral, and circular, in addition to the straight or uniform for comparison. These five configurations are tested and analyzed experimentally depending on the thermo-hydraulic performance for summer cooling requirements with variation of Re in the range of 18041–40843. The results show that changing the uniform design of the EAHE with fixed pipe length enhances both the heat transfer process and pressure loss values. At the same operating conditions, the circular design has the best performance compared to the other ones. For all pipe shapes, the cooling effect increases with the increase of air Re. The thermal-hydraulic performance of the circular design pipe is higher than that of the other pipe designs. The highest coefficient of performance (COP) average values that can be obtained at Re = 18041 is 3.05 for circular shape and enhances by 48.08 % compared to uniform shape. The effectiveness of EAHE with circular shape is improved by about 3.52 % compared to uniform shape at Re = 18041. Spiral design is optimum design based on the Nu value which reaches about 48 with enhancement 12.56 % and 0.34 % compared to uniform and circular shapes respectively, at Re = 40843. The hydrothermal performance factor is highest in the case of circular shape with value about 21.9 at Re = 21257. By increasing Re, the drawbacks of the increasing in the total entropy generation are reflected negatively on the exergy efficiency. The specific cost of the circular shape at Re = 40843 is the optimum value by about 0.7 $/W. Spiral and circular shapes have a decrease of CO₂ emissions less than uniform shape by percentage varied from 2.93 % to 13.84 % for decrease in the Re from 21257 to 40843. It is concluded that using EAHE with four new shapes is highly efficient in increasing cooling capacity and energy consumption in buildings.

管道布局设计对土风换热器（EAHE）系统的热工水力特性有很大影响。因此，本研究提出了四种新的地埋管设计配置：低到高到低、高到低到高、螺旋和圆形，此外还有直管或均匀管供比较。根据夏季制冷要求的热工水力性能，对这五种配置进行了实验测试和分析，Re 变化范围为 18041-40843 。结果表明，改变管道长度固定的 EAHE 的均匀设计可提高传热过程和压力损失值。在相同的运行条件下，圆形设计与其他设计相比性能最佳。对于所有形状的管道，冷却效果都随着空气 Re 的增加而增加。圆形设计管道的热液压性能高于其他管道设计。在 Re = 18041 时，圆形管道的最高性能系数（COP）平均值为 3.05，比均匀形状的管道提高了 48.08%。在 Re = 18041 时，圆形 EAHE 的效率比均匀形状提高了约 3.52%。在 Re = 40843 条件下，根据 Nu 值，螺旋形设计是最佳设计，其 Nu 值约为 48，与均匀形和圆形相比，分别提高了 12.56 % 和 0.34 %。在 Re = 21257 时，圆形的水热性能系数最高，约为 21.9。随着 Re 值的增加，总熵产生量增加的缺点会对放热效率产生负面影响。在 Re = 40843 时，圆形的具体成本是最佳值，约为 0.7 美元/瓦。当 Re 值从 21257 降至 40843 时，螺旋形和圆形比均匀形的二氧化碳排放量减少了 2.93 % 至 13.84 %。由此得出结论，使用四种新形状的 EAHE 能够高效地提高建筑物的制冷能力和能耗。

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引用次数: 0

Dynamic thermal simulation of a tree-shaped district heating network based on discrete event simulation 基于离散事件模拟的树状区域供热网络动态热模拟

IF 9 1区工程技术 Q1 ENERGY & FUELS

Energy

Pub Date : 2024-11-08 DOI: 10.1016/j.energy.2024.133775

Zichan Xie , Haichao Wang , Pengmin Hua , Maximilian Björkstam , Risto Lahdelma

The computational complexity involved in modelling district heating (DH) networks impedes the integration of network operations into comprehensive DH system studies. We developed a flexible, accurate, and fast dynamic thermal simulation model utilising discrete event simulation (DES). This model is versatile, suitable for any tree-shaped DH network with a central heating plant and can estimate node temperatures and calculate pipe heat losses. The speed of the model is improved via using variable time steps and by incorporating two advanced techniques: lazy evaluation and a customised priority queue. To further improve the computational speed, we developed a technique to eliminate redundant sampling points. This model was tested and demonstrated excellent consistency with actual measurements. Remarkably, reducing sampling points can speed up the simulation by a factor of three without compromising the temperature accuracy. A 72-day simulation of a network with 102 pipes was completed within 0.219 s. Our findings highlight the significant potential of the DES model for large-scale dynamic network simulations and offer a promising solution for DH network simulations and system optimisation.

区域供热（DH）网络建模所涉及的计算复杂性阻碍了将网络运行纳入全面的 DH 系统研究。我们利用离散事件仿真（DES）开发了一种灵活、准确、快速的动态热仿真模型。该模型用途广泛，适用于任何带有集中供暖设备的树状 DH 网络，可估算节点温度并计算管道热损失。通过使用可变时间步长并结合两种先进技术：懒惰评估和定制优先队列，该模型的速度得到了提高。为了进一步提高计算速度，我们开发了一种消除冗余采样点的技术。经过测试，该模型与实际测量结果具有极佳的一致性。值得注意的是，在不影响温度精度的情况下，减少采样点可将模拟速度提高三倍。我们的研究结果凸显了 DES 模型在大规模动态网络模拟方面的巨大潜力，并为 DH 网络模拟和系统优化提供了一个前景广阔的解决方案。

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引用次数: 0

A geographic multi-scale machine learning framework for predicting solar irradiation on tilted surfaces 用于预测倾斜表面太阳辐照的地理多尺度机器学习框架

IF 9 1区工程技术 Q1 ENERGY & FUELS

Energy

Pub Date : 2024-11-08 DOI: 10.1016/j.energy.2024.133767

Sameer Al-Dahidi , Bilal Rinchi , Raghad Dababseh , Osama Ayadi , Mohammad Alrbai

This study addresses the challenge of improving Global Tilted Irradiation (GTI) predictions, with Jordan serving as the case study. The novelty of the work lies in developing machine learning models that predict GTI at national, regional (3 regions), and city-specific (12 cities) levels, a previously unexplored approach in the literature. The research examines the comparative efficiency of using a single model for an entire country versus tailored models for individual regions and cities, shedding light on the trade-offs in model evaluation. Various regression models, including Neural Networks (NNs), Linear Regression (LR), Regression Trees (RTs), Ensemble of Regression Trees (ERTs), Support Vector Machine (SVM), and Kernel Approximation, were evaluated using performance metrics such as Root Mean Square Error (RMSE), Mean Absolute Error (MAE), Mean Absolute Percentage Error (MAPE), and coefficient of determination (R²). NNs consistently performed best, achieving the lowest RMSE (1.5787 kWh/m²) and highest R² (99.8600 %) at the regional level. Sensitivity analysis further explored the impact of different time resolutions, revealing that monthly data outperformed daily data in terms of accuracy and computational efficiency. Ultimately, we conclude that region-specific models and monthly data resolution are optimal for practical GTI prediction.

本研究以约旦为案例，探讨了改进全球倾斜辐照（GTI）预测的挑战。这项工作的新颖之处在于开发了机器学习模型，可在国家、地区（3 个地区）和城市（12 个城市）层面预测全球倾斜辐照度，这是此前文献中尚未探索过的方法。该研究考察了针对整个国家使用单一模型与针对个别地区和城市使用定制模型的效率比较，从而揭示了模型评估中的权衡问题。研究利用均方根误差 (RMSE)、平均绝对误差 (MAE)、平均绝对百分比误差 (MAPE) 和判定系数 (R2) 等性能指标对各种回归模型进行了评估，包括神经网络 (NN)、线性回归 (LR)、回归树 (RT)、回归树集合 (ERT)、支持向量机 (SVM) 和核逼近模型。NN 始终表现最佳，在区域层面实现了最低的 RMSE（1.5787 kWh/m2）和最高的 R2（99.8600 %）。敏感性分析进一步探讨了不同时间分辨率的影响，结果表明月度数据在准确性和计算效率方面优于日度数据。最终，我们得出结论，针对特定地区的模型和月度数据分辨率是实际 GTI 预测的最佳选择。

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引用次数: 0

A systematic methodology for selecting optimal technology for waste heat utilization in food processing industry 选择食品加工业余热利用最佳技术的系统方法学

IF 9 1区工程技术 Q1 ENERGY & FUELS

Energy

Pub Date : 2024-11-08 DOI: 10.1016/j.energy.2024.133751

Mladen Josijevic, Vladimir Vukasinovic, Dusan Gordic, Vanja Sustersic, Dubravka Zivkovic, Jelena Nikolic

Utilizing waste heat that is rejected from thermal processes can greatly enhance the industry's energy balance. Identifying potential waste heat sources in the food and beverage processing industry and making estimations for their possible utilization can be an extremely challenging undertaking. To determine waste heat potentials in the food processing industry and to select an optimal technology for its utilization a novel systematic methodology based on the comprehensive energy audit and mathematical optimization has been developed. The developed mixed integer nonlinear programming model incorporates all novel and the most commonly employed technologies to utilize waste heat.

The developed systematic methodology is tested on a case study, of a milk and dairy production facility. Obtained results have shown that up to 53 % of the available waste heat can be used in the scenario of limited investment costs. Otherwise, in the scenario when investment costs are not set as a limitation, 75 % of waste heat can be used, according to plant demands. Harmonising production processes is necessary to use all the waste heat. The developed systematic methodology can be applied to any food processing industry and other facilities producing waste heat because it presents a universal approach.

利用热加工过程中排出的余热可以大大提高行业的能源平衡。在食品和饮料加工业中确定潜在的废热源并对其可能的利用率进行估算是一项极具挑战性的工作。为了确定食品加工业的余热潜力，并为其利用选择最佳技术，我们开发了一种基于综合能源审计和数学优化的新型系统方法。所开发的混合整数非线性编程模型包含了所有新型和最常用的余热利用技术。结果表明，在投资成本有限的情况下，最多可利用 53% 的可用余热。否则，在投资成本不受限制的情况下，根据工厂需求，75% 的余热可被利用。要利用所有余热，必须协调生产流程。所开发的系统方法适用于任何食品加工业和其他产生余热的设施，因为它提供了一种通用方法。

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引用次数: 0

How does China's Winter Heating policy impact corporate sustainable development performance? 中国的冬季取暖政策如何影响企业的可持续发展绩效？

IF 9 1区工程技术 Q1 ENERGY & FUELS

Energy

Pub Date : 2024-11-08 DOI: 10.1016/j.energy.2024.133771

Tianqi Liu , Liwen Wang , Ping Zhou , Hailing Li

The China's Winter Heating policy plays a crucial role in China's regional environmental regulatory framework, particularly concerning the challenge of atmospheric pollution. This study investigates the impact of this policy on corporate sustainable development performance in the “2 + 26” cities of the Beijing, Tianjin and Hebei region (BTH2+26) at the micro-level. It employs a dual perspective focusing on emission reduction and efficiency enhancement (i.e., sustainable development), utilizing a DID model based on the policy shock from the first implementation of the China's Winter Heating policy in 2017. The findings indicate that this policy not only effectively promotes pollution reduction among heavy-polluting companies, thereby enhancing their environmental performance, but also improves their financial performance. Robustness tests confirm the significance of these results. Mechanism analysis reveals that the policy's facilitative effect on heavy-polluting companies is mediated through promoting green innovation and easing financing constraints, with the innovation investment being the main channel to promote the corporate environmental performance. Heterogeneity analysis shows differential impacts across company nature and industry attributes, highlighting the policy's varied effects on environmental performance and financial performance across sectors. This research contributes empirical evidence and policy insights into enhancing sustainable development performance among heavy-polluting companies under the China's Winter Heating policy framework.

中国冬季取暖政策在中国区域环境监管框架中发挥着至关重要的作用，尤其是在应对大气污染挑战方面。本研究从微观层面探讨了该政策对京津冀 "2+26 "城市（BTH2+26）企业可持续发展绩效的影响。研究采用了以减排和增效（即可持续发展）为核心的双重视角，利用基于 2017 年中国冬季取暖政策首次实施时的政策冲击的 DID 模型。研究结果表明，该政策不仅有效促进了重污染企业的污染减排，从而提高了企业的环境绩效，而且改善了企业的财务绩效。稳健性检验证实了这些结果的显著性。机理分析表明，该政策对重污染企业的促进作用是通过促进绿色创新和缓解融资约束来实现的，其中创新投资是促进企业环境绩效的主要渠道。异质性分析表明了不同公司性质和行业属性的不同影响，凸显了该政策对不同行业环境绩效和财务绩效的不同影响。本研究为在中国冬季取暖政策框架下提高重污染企业的可持续发展绩效提供了经验证据和政策见解。

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引用次数: 0

Experimental investigation on thermodynamic and environmental performance of a novel ocean thermal energy conversion (OTEC)-Air conditioning (AC) system 新型海洋热能转换（OTEC）-空气调节（AC）系统的热力学和环境性能实验研究

IF 9 1区工程技术 Q1 ENERGY & FUELS

Energy

Pub Date : 2024-11-07 DOI: 10.1016/j.energy.2024.133760

Yibo Zhou, Wenzhong Gao, Yuan Zhang, Zhen Tian, Fei Wang, Runbo Gao

In the field of isolated island energy supply, the OTEC system is considered promising due to its large storage capacity, and pollution-free characteristics. To improve energy efficiency, polygeneration systems have gradually become a research hotspot for their low cost and high return features. In this context, a novel Ocean Thermal Energy Conversion system integrated with an air conditioning unit (OTEC-AC) is introduced, demonstrating capabilities in electricity, cooling capacity, and fresh water production by experiments. The effects of various flow rates and temperatures of the heat and cold sources, along with the air-conditioning system water flow rate on the system performance is explored. Besides, the overall performance of the OTEC-AC is compared with four representative OTEC models. The results indicate that there is a threshold for the influence of cold and heat source flow rate on the performance of power generation system. The OTEC-AC system shows a highest net power of 132.6 W, cooling capacity of 2.14 kW, condensate production of 3.24 kg/h, and achieves a system exergy efficiency and CO₂ reduction of 34.7 % and 5801 kg/year, respectively. The annual CO₂ reduction per kilowatt of installed capacity of the system is increased by 135.6 %, compared with the conventional OTEC system.

在孤岛能源供应领域，有机热电联产系统因其储量大、无污染等特点而被认为前景广阔。为了提高能源效率，多联产系统以其低成本、高回报的特点逐渐成为研究热点。在此背景下，本文介绍了一种新型海洋热能转换系统，该系统与空调装置（OTEC-AC）集成，通过实验展示了其在发电、制冷和淡水生产方面的能力。实验探讨了各种冷热源流速和温度以及空调系统水流量对系统性能的影响。此外，还将 OTEC-AC 的整体性能与四个具有代表性的 OTEC 模型进行了比较。结果表明，冷热源流量对发电系统性能的影响存在一个临界值。OTEC-AC 系统的最高净功率为 132.6 W，制冷量为 2.14 kW，冷凝水产量为 3.24 kg/h，系统能效和二氧化碳减排量分别为 34.7 % 和 5801 kg/年。与传统的 OTEC 系统相比，该系统每千瓦装机容量的二氧化碳年减排量提高了 135.6%。

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引用次数: 0

Degradation-infused energy portfolio allocation framework: Risk-averse fair storage participation 退化注入式能源组合分配框架：风险规避型公平储能参与

IF 9 1区工程技术 Q1 ENERGY & FUELS

Energy

Pub Date : 2024-11-07 DOI: 10.1016/j.energy.2024.133688

Parikshit Pareek , L.P. Mohasha Isuru Sampath , Anshuman Singh , Lalit Goel , Hoay Beng Gooi , Hung Dinh Nguyen

This work proposes a novel degradation-infused energy portfolio allocation (DI-EPA) framework for enabling the participation of battery energy storage systems in multi-service electricity markets. The proposed framework attempts to address the challenge of including the rainflow algorithm for cycle counting by directly developing a closed-form of marginal degradation as a function of dispatch decisions. Further, this closed-form degradation profile is embedded into an energy portfolio allocation (EPA) problem designed for making the optimal dispatch decisions for all the batteries together, in a shared economy manner. We term the entity taking these decisions as ‘facilitator’ which works as a link between storage units and market operators. The proposed EPA formulation is quipped with a conditional-value-at-risk (CVaR)-based mechanism to bring risk-averseness against uncertainty in market prices. The proposed DI-EPA problem introduces fairness by dividing the profits into various units using the idea of marginal contribution. Simulation results regarding the accuracy of the closed-form of degradation, effectiveness of CVaR in handling uncertainty within the EPA problem, and fairness in the context of degradation awareness are discussed. Numerical results indicate that the DI-EPA framework improves the net profit of the storage units by considering the effect of degradation in optimal market participation.

这项研究提出了一种新颖的边际衰减能源组合分配（DI-EPA）框架，使电池储能系统能够参与多服务电力市场。所提出的框架试图通过直接开发边际退化的闭合形式作为调度决策的函数，来解决将雨流算法纳入周期计数的挑战。此外，该闭式衰减曲线被嵌入到能源组合分配（EPA）问题中，旨在以共享经济的方式为所有电池做出最优调度决策。我们将做出这些决策的实体称为 "促进者"，它是存储单元与市场运营商之间的纽带。建议的 EPA 方案采用基于条件风险价值 (CVaR) 的机制，以规避市场价格不确定性带来的风险。提议的 DI-EPA 问题利用边际贡献的理念将利润划分到不同的单位，从而引入了公平性。仿真结果涉及退化封闭式的准确性、CVaR 在 EPA 问题中处理不确定性的有效性以及退化意识背景下的公平性。数值结果表明，DI-EPA 框架通过考虑退化对最优市场参与的影响，提高了存储单元的净利润。

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引用次数: 0

Does technological progress mode affect just energy transition? A seemingly unrelated regression analysis based on Chinese provincial panel data 技术进步模式影响能源转型吗？基于中国省级面板数据的貌似无关回归分析

IF 9 1区工程技术 Q1 ENERGY & FUELS

Energy

Pub Date : 2024-11-07 DOI: 10.1016/j.energy.2024.133753

Jingrong Dong , Wenqing Zhang , Yuke Chen , Tingting Li

Just energy transition (JET) refers to the process of shifting from fossil-fuel-based energy systems to more sustainable and renewable energy sources in a manner that is inclusive and socially fair. Technological progress is a key driver of the energy transition. Selecting an appropriate technological progress mode (TPM) to drive JET that harmonizes environmental conservation with employment stability is crucial for economies to achieve sustainable development. Based on seemingly unrelated regression (SUR) analysis, this research uses provincial panel data of China from 2001 to 2020 to examine the effects and underlying mechanisms of various TPMs on JET. We first construct a translog cost function incorporating four TPMs, including technology import, technology transformation, cooperative research and development (R&D), and independent R&D. The study then systematically estimates and contrasts the factor bias and utilization tendencies associated with these TPMs. The findings indicate that (1) technology import does not directly facilitate JET as it leads to neutral technological progress; (2) technology transformation and cooperative R&D, associated with energy-biased technological progress, exhibit a tendency toward energy use and labor saving, which hinders JET; (3) independent R&D, linked with labor-biased technological progress, demonstrates a labor-using and energy-saving orientation, which supports JET; (4) the adverse effects of technology transformation and cooperative R&D on JET can be mitigated through enhanced environmental regulation, increased environmental taxation, and the provision of low-carbon subsidies. We offer policy recommendations for the Chinese government in promoting TPMs that foster JET while also providing insights and experiences that are beneficial to economies at various development stages in their pursuit of JET.

公正的能源转型（JET）是指以包容和社会公平的方式，从基于化石燃料的能源系统转向更可持续和可再生能源的过程。技术进步是能源转型的关键驱动力。选择适当的技术进步模式（TPM）来驱动 JET，使环境保护与就业稳定相协调，对于各经济体实现可持续发展至关重要。本研究基于似非相关回归（SUR）分析，利用中国 2001 年至 2020 年的省级面板数据，考察了各种技术进步模式对 JET 的影响及其内在机制。首先，我们构建了一个包含四种 TPM 的 translog 成本函数，包括技术引进、技术改造、合作研发和自主研发。然后，研究系统地估算并对比了与这些 TPM 相关的要素偏差和利用倾向。D与偏重劳动力的技术进步相关联，表现出使用劳动力和节约能源的倾向，这支持了JET；(4) 技术改造和合作研发对JET的不利影响可以通过加强环境监管、增加环境税和提供低碳补贴来缓解。我们为中国政府推广促进联合技术与转让的技术产权措施提供了政策建议，同时也为处于不同发展阶段的经济体提供了有益于其追求联合技术与转让的见解和经验。

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引用次数: 0

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