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Under the dual-carbon target, hydrogen energy, as a zero-carbon secondary energy source, has great scope for replacing fossil feedstocks in the fields of energy, transportation and industry. However, the current research on the competitiveness of hydrogen energy in various fields is not sufficiently addressed. In this paper, we use the LEAP model to predict the future scale of hydrogen use and the two-factor learning curve to predict the trend of hydrogen price change from 2025 to 2050, using Qinghai Province as the research background. At the same time, considering the carbon emission reduction benefits and raw material costs, the competitiveness of hydrogen energy in energy, transportation, industry and other fields in the future is compared. The results show that: 1) The hydrogen load scale in Qinghai Province will grow fast from 2025 to 2030. From 2030 to 2040, it slows under the steady and basic scenarios but remains high under the accelerated one. By 2040, the consumption scales are 1.057 million, 649,000 and 442,000 tons respectively. 2) The price of hydrogen energy will drop rapidly from the current 28 CNY/kg to about 20 CNY/kg in the next 5 years. By 2040, the price of hydrogen energy will be reduced to about 17 CNY/kg. 3) In terms of hydrogen energy competitiveness, when carbon emissions are not taken into account, hydrogen energy is currently competitive in the transportation field. During 2032-2038, it will be competitive in the field of methanol synthesis. By 2040, hydrogen energy will not be competitive in the fields of ammonia synthesis and power/heating. When considering carbon emissions, the competitiveness of hydrogen energy in the transportation field will become greater. The competitive year in the field of methanol synthesis will be 1-2 years ahead. By 2040, it will not be competitive in the field of synthetic ammonia and power/heating, but the gap will be significantly reduced due to the consideration of carbon emissions. [ABSTRACT FROM AUTHOR]

Against the backdrop of increasingly prominent environmental issues, new energy consumption issues, and energy supply and demand balance issues, the optimization of multi time scale operation of distributed electro hydrogen coupling systems has become a research focus. Based on this, this article optimizes the multi time scale operation of a distributed electric hydrogen coupling system that takes into account grid interaction. By designing a system framework for distributed electro hydrogen coupling systems, operational strategies for each system were proposed. Analyzed the uncertainty and response characteristics of wind and solar power generation units and load demand, and constructed a multiple uncertainty model for distributed electric hydrogen coupling system. At the same time, a three stage, multi time scale operation optimization model of the electric hydrogen coupling system was constructed based on the response characteristics of the distributed electric hydrogen coupling system. The construction of these models reduced scheduling costs by 12.55% and increased clean energy consumption rate by 13.50%. [ABSTRACT FROM AUTHOR]

To optimize the energy supply potential and complementary advantages of distributed energy, this paper focuses on the dispatching optimization of cogeneration virtual power plant considering uncertainty. First of all, wind power, photovoltaic, combined heat and power (CHP) units, electric boilers, and controllable loads are integrated into a CHP virtual power plant. Then, carbon capture and electric-to-gas devices are introduced to realize carbon recycling. Furthermore, quantify the risk of real-time dispatching of virtual power plants through uncertainty scenario generation and conditional value at risk (CVaR) theory, and the multi-objective stochastic dispatching optimization model of virtual power plants is built with the aim at minimizing the operation cost, carbon emissions, and operation risk as the objectives, and the CRITIC weighting method is adopted to solve it. Finally, the calculation results show that: 1) the electric boiler can use wind and photovoltaic power to supply heat for the system, reduce the dependence ofthe virtual power plant (VPP) on the CHP unit, and make the electric output of the unit more flexible. 2) The risk quantification method proposed can fully measure the risk situation in real-time dispatching, arrange the wind and photovoltaic power generation plan and backup plan more reasonably, and enable the VPP to get more benefits while avoiding the risks in real-time dispatching. [ABSTRACT FROM AUTHOR]

Taking an industrial park as an example, this study aims to analyze the characteristics of a distribution network that incorporates distributed energy resources (DERs). The study begins by summarizing the key features of a distribution network with DERs based on recent power usage data. To predict and analyze the load growth of the industrial park, an improved back-propagation algorithm is employed. Furthermore, the study classifies users within the industrial park according to their specific power consumption and supply requirements. This user segmentation allows for the introduction of three constraints: node voltage, wire current, and capacity of DERs. By incorporating these constraints, the study constructs an optimization model for the distribution network in the industrial park, with the objective of minimizing the total operation and maintenance cost. The primary goal of these optimizations is to address the needs of DERs connected to the distribution network, while simultaneously mitigating their potential adverse impact on the network. Additionally, the study aims to enhance the overall energy efficiency of the industrial park through more efficient utilization of resources. [ABSTRACT FROM AUTHOR]

Based on the PM6:Y6 binary system, a novel non-fullerene acceptor material, D18-Cl, was doped into the PM6:Y6 blend to fabricate the active layer. The effects of different doping ratios of D18-Cl on organic solar cells were investigated. The best-performing organic solar cell was achieved when the doping ratio of D18-Cl reached 20 wt%. It exhibited a short-circuit current of 28.13 mA/cm2, a fill factor of 70.25%, an open-circuit voltage (Voc) of 0.81 V, and a power conversion efficiency of 16.08%. The introduction of an appropriate amount of D18-Cl expanded the absorption spectrum of the active layer, improved the morphology of the active layer, reduced large molecular aggregation and defects, minimized bimolecular recombination, and optimized the collection efficiency of charge carriers. These results indicate the critical importance of selecting an appropriate third component in binary systems and optimizing the doping ratio to enhance the performance of ternary organic solar cells. [ABSTRACT FROM AUTHOR]

Output instability is one of the important constraints limiting the large-scale application of renewable energy. The development of comprehensive energy systems can effectively improve energy utilization efficiency, but there is still a problem of randomness in renewable energy output. The paper conducts research on the uncertainty of distributed energy output and load, constructs a comprehensive energy system optimization model that takes into account the robustness of bilevel programming, and solves the model using the firefly algorithm. The calculation results show that optimizing uncertainty can significantly reduce the actual operating costs of the system, with a maximum reduction of 14.43%. When the distributed wind power interval is within [0190], a dynamic balance between cost and consumption rate can be achieved. [ABSTRACT FROM AUTHOR]

This research focuses on the fabrication and optimization of large-area PM6:D18-CL:Y6 ternary organic solar cells, with a particular emphasis on film thickness, annealing temperature, and the connection configuration's impact on device performance. The experimental findings indicate that an optimal film thickness of approximately 105 nm fosters the formation of a well-interconnected network, reducing defects and significantly improving both the fill factor, which reaches 46.2%, and the power conversion efficiency (PCE) at 7.2%. An annealing temperature of 110 °C stands out as the ideal condition, resulting in the highest PCE of 8.15%. Notably, excessively high annealing temperatures lead to material aggregation, compromising device performance. Regarding the connection configurations, the study demonstrates that the 5-series 4-parallel arrangement surpasses traditional setups, achieving an impressive output power of 0.11 W. In conclusion, the meticulous control of the film thickness and annealing temperature is paramount for achieving a high PCE in large-area PM6:D18-CL:Y6 ternary organic solar cells. The 5-series 4-parallel configuration exhibits considerable promise for an enhanced power output, offering valuable insights into the development and industrialization of large-area organic solar cells. [ABSTRACT FROM AUTHOR]

The existing research on critical peak price (CPP) decision-making ignores the difference in risk appetite between industries within the consumer population, resulting in a serious lag in the enthusiasm of some users to respond to CPP, and unsatisfactory improvement of power systems and carbon emission reduction on the supply and demand side. Firstly, the problem of consumer risk appetite was comprehensively analyzed, and the industrial consumer population was secondarily stratified according to the influencing factors and the enthusiasm of responding to CPP, namely: stubborn, active and conformist, and quantitatively verified by cluster analysis. Secondly, by combing the relevant paths of CPP decision-making, the critical-peak window determination model and CPP multi-objective optimization model were constructed, and the calculation of relevant indicators was introduced. Finally, taking 10 industrial enterprises in a city in Sichuan Province as an example, the clustering method was used to verify the stratification results, and the index analysis method was used to measure the load and carbon emission improvement of two typical enterprises after CPP optimization. The results showed that the stubborn users insist on using electricity, the improvement effect of load and carbon emission reduction was poor, and additional production costs will be caused. The conformist and active users had high sensitivity to electricity price fluctuations, good load and carbon emission reduction improvement effects, and significantly reduced electricity costs. [ABSTRACT FROM AUTHOR]

Semitransparent organic photovoltaics (ST‐OPVs) have great application potential in photovoltaic buildings and wearable devices. Studies have proved that power conversion efficiency (PCE) and average visible transmittance (AVT) reveal more balanced in pseudoplanar heterojunction (PPHJ) structure than in bulk heterojunction (BHJ) structure. An interesting approach named low temperature sequential deposition (LTSD)—spin‐coating the small molecule acceptor (A) Y6 on polymer donor (D) PM6—is proposed to form an efficient PPHJ structure. In the LTSD process, small molecule Y6 will diffuse through amorphous PM6 layer which means that Y6 finally aggregates at the bottom of active layer and results in vertical gradient concentration distribution. In this structure, adjustment of D:A ratio can achieve higher AVT with maintaining less PCE loss compared with BHJ structure. The fabricated LTSD devices provide PCE of 12.36% (AVT of 23.19%) at 45:40 nm (D:A layer thickness) and PCE of 11.26% (AVT of 25.10%) at 40:40 nm (D:A), while BHJ devices provide PCE of 11.43% (AVT of 21.32%) at 85 nm (D:A = 1:1.2 w). Besides, the LTSD devices are more stable than BHJ devices due to smoother surface. LTSD strategy provides a new approach for achieving PPHJ structure and high‐performance ST‐OPVs. [ABSTRACT FROM AUTHOR]

The electrolyte is one of the key components of dye-sensitized solar cells' (DSSC) structure. In this paper, the electrolyte formulation of a new DSSC with external photoanode structure was studied. Based on the idea that the electrolyte should match the light absorption and light path, iodine series electrolytes with different concentrations were configured and used in the experiment. The results showed that the external photoanode structure solar cells assembled with titanium electrode had the best photoelectric conversion ability when the concentration of I2 was 0.048 M. It achieved the open circuit voltage of 0.71 V, the short circuit current of 8.87 mA, and the filling factor of 57%. [ABSTRACT FROM AUTHOR]

Summary: With the continuous opening of China's electricity market, a large number of third‐party electricity retailers have poured into the electricity market. Electricity retailers are the bridge between the main player of the electricity market. In view of the large number and variety of electricity retailers in the current electricity market, this paper divides the electricity retailers that have been publicized in China into five categories. In view of the uncertainty of the credit evaluation standard of electricity retailers, this paper determines the cloud model scale of the risk level of the electricity retailers; selects three primary indicators, eight secondary indicators, and 20 tertiary indicators to construct the credit risk evaluation indicator system of the electricity retailer. This paper also builds a computing model combining intuitionistic fuzzy analytic hierarchy process (IFAHP) with cloud model; obtains the final evaluation score by combining the certainty of cloud model with intuitionistic fuzzy weight, the qualitative to quantitative change of the indicator is realized, and makes the fuzzy concept of credit rating of electricity retailers get a quantitative change. From the model results, it can be seen that the risk score of the electricity grid asset retailers is 14.8666, which is the lowest risk; the independent electricity retailers has a risk score of 26.9706, which is the highest risk. Compared with the traditional AHP‐cloud model, this method is not only more objective, but also can obtain more information such as the distribution of index values from entropy and hyper entropy. [ABSTRACT FROM AUTHOR]

SUMMARY Integrated energy system is a very important way to improve energy efficiency. Based on the combined heating cooling and power system, combined with energy storage equipment, a cross‐regional integrated energy system scheduling optimization problem is studied. An integrated energy system scheduling optimization model is established that meets the requirements of electrical, heating, and cooling load under a variety of energy sources while both considering the interaction of electrical, heating, and cooling load between regions, and complementation of them within one region. Meanwhile, the value at risk (VaR) theory is introduced and the operating constraints of equipment in the integrated energy system fully considered, the integrated energy system scheduling model with VaR is established. The example shows that the model can realize multi‐type electrical, heating, and cooling load optimized by schedule across regions under the premise of satisfying the balance of energy supply and demand, which can reduce the system operation cost. The sensitivity analysis of the minimum expected cost and the influencing factors of conditional VaR is carried out to verify the validity and feasibility of the proposed model. An integrated energy system scheduling optimization model is established that meets the requirements of electrical, heating, and cooling load under a variety of energy sources while both considering the interaction of electrical, heating, and cooling load between regions, and complementation of them within one region.By using the conditional value at risk theory to consider various types of the integrated energy system complements and evaluates the operational risk of the system under optimal operating conditions of the system.The total cost of system scheduling operation is proportional to the storage capacity, which is inversely proportional to the heat storage capacity and inversely proportional to the pipeline capacity within a certain interval. [ABSTRACT FROM AUTHOR]

The decision‐making and risk assessment of electricity purchase and sales is the key to adapt to the electricity market for independent electricity retailers in China. This research carried out the purchase and sales risks of electricity for electricity retailers and constructed the multi‐level market purchase and sales combination optimization model. Based on the portfolio optimization theory, the conditional value at risk theory (CVaR) was proposed. Based on the evaluation index about the conditional risk profit and CVaR, electricity retailers purchase and sales combined optimization model has been constructed to explore the impact of purchase and sales risks by different factors in multi‐level electricity market. The example analysis was carried out by the fixed spread mode and the linkage spread mode. The results showed that the mathematical mean and variance of market spread had great influence on the electricity purchase and sales combination. Especially in the mature electricity market, the mathematical mean of spread and risk in medium‐ and long‐term market was smaller than that in spot market, and the best point of the electricity purchase and sales combination was shown on the smallest value of CVaR, while the electricity purchase and sales combination was optimal under limited conditions. [ABSTRACT FROM AUTHOR]

The sales aspect of electricity reform is one of the focuses of current reform in China. Independent retailers are involved in the purchase of electricity, which is a sign of a mature electricity market. With the increasing degree of market opening, it is expected to become an important link between the generation side and demand side, and its degree of participation will directly affect the benefits of the demand response. From the analysis of the operation pattern of future electricity retailers that are involved in optimal generation dispatching, the load-calculation model of the customer response and the dispatching model of electricity retailers involved in generation are established. Then, based on the principle of dynamics, a comprehensive assessment model is established. The results show that customers' response to electricity retailers involved in the generation dispatch can improve the load rate by about 4%. The overall efficiency of various stakeholders is positive, and the investment cost of the government environmental management is gradually decreased. [ABSTRACT FROM AUTHOR]

As an efficient way to deal with the exhaustion of traditional fossil fuels, new energy power generation has obtained much attention from the Chinese Government. In this context, more and more new energy power generation groups that consist of large numbers of regional enterprises have been founded and developed rapidly. However, researches related to comprehensive benefit evaluation of group-affiliated new energy power generation enterprises is still blank in China, which will hinder the benefit growth and sustainable development of such enterprises. A novel hybrid evaluation indicator system is proposed from both perspectives of sustainability and the internal management within the groups. Considering the preference information given on each of the indicators is featured by multi-source and multi-form, an evaluation framework to integrate the blended and complex evaluation information is designed. In addition, different from previous studies, this paper employs a combined technique of Stochastic Transformation for Blended Information (STBI) method and the Technique for Order Preference by Similar to Ideal Solution (TOPSIS) to simulate the evaluation process and rank the comprehensive benefit of evaluation objects. It can efficiently handle the comprehensive evaluation problems with blended and complex evaluation information and preserve the initial evaluation information to the utmost simultaneously. Finally, this paper applied the evaluation model to empirical research and the results show that the model meets the actual situation of the new energy power generation group and can provide a certain reference value. [ABSTRACT FROM AUTHOR]

Carbon emissions of power industry in China have accounted for more than half of the total emissions. How to decrease them is important for realizing carbon emission reduction. This paper proposes a carbon market feedback mechanism to power market, comprehensively considering the influence of generation structure, carbon intension, and technological progress on carbon emission reduction in power industry, and builds a potential model based on dynamic system. Operation system results show that the increasing trend of carbon emission can be controlled effectively but always with a lag. At the same time, sensitivity analysis results show that carbon emission reduction can be better realized by adjusting power structure and improving technological level; the former can reduce 32% and the latter can reduce 60% at most. [ABSTRACT FROM AUTHOR]

A peak-to-average power ratio (PAPR)-aware dual-mode power amplifier (PA) for short-range wireless communication in the subgigahertz band is proposed in this brief. By carefully choosing the bias, the dual-mode PA achieves the measured output P1 dB (OP1 dB) of 13.6 dBm with a PAE of 25.5%. Furthermore, a dynamic load modulation network is utilized to optimize the PA's efficiency at back-off power. A power-control loop is proposed to detect the input signal PAPR in real time and flexibly reconfigure the PA's operation modes. With these proposed techniques, the PAE has been improved by ×2.61 at 7-dB back-off power. The measurement shows that the subgigahertz-band PA archives an adjacent channel leakage ratio (ACLR1) of −37.3 dBc and an average/peak error vector magnitude of −30.4 dB/−20.5 dB at 8.9-dBm output power for ∼5-dB-PAPR 16-quadrature-magnitude-modulation LTE signals with 5-MHz bandwidth with the power control loop enabled. The PAPR-aware dual-mode PA, powered by a 2-V supply, occupies a 2.52-mm2 die area in a 180-nm CMOS. [ABSTRACT FROM PUBLISHER]

A fully-integrated reconfigurable dual-band (760–960 MHz and 2.4–2.5 GHz) transceiver (TRX) for short range wireless communications is presented. The TRX consists of two individually-optimized RF front-ends for each band and one shared power-scalable analog baseband. The sub-GHz receiver has achieved the maximum 75 dBc 3rd-order harmonic rejection ratio (HRR3) by inserting a Q-enhanced notch filtering RF amplifier (RFA). In 2.4 GHz band, a single-ended-to-differential RFA with gain/phase imbalance compensation is proposed in the receiver. A ΣΔ fractional-N PLL frequency synthesizer with two switchable Class-C VCOs is employed to provide the LOs. Moreover, the integrated multi-mode PAs achieve the output P1dB (OP1dB) of 16.3 dBm and 14.1 dBm with both 25% PAE for sub-GHz and 2.4 GHz bands, respectively. A power-control loop is proposed to detect the input signal PAPR in real-time and flexibly reconfigure the PA's operation modes to enhance the back-off efficiency. With this proposed technique, the PAE of the sub-GHz PA is improved by ×3.24 and ×1.41 at 9 dB and 3 dB back-off powers, respectively, and the PAE of the 2.4 GHz PA is improved by ×2.17 at 6 dB back-off power. The presented transceiver has achieved comparable or even better performance in terms of noise figure, HRR, OP1dB and power efficiency compared with the state-of-the-art. [ABSTRACT FROM PUBLISHER]

A stacked 2.4-GHz CMOS power amplifier (PA) with a mode switching scheme is proposed to enhance the back-off efficiency for wireless local area network applications. By means of dynamically tuning the bias and optimal load with a power-detecting controller, the proposed mode switching scheme effectively improves the power-added efficiency (PAE) of the PA by \times2 at 5-dB back-off power. Besides, with the transistor stacking and envelope-tracked self-biasing techniques, the PA, powered by a 5.6-V supply, achieves an output P1dB of 27 dBm with a PAE of 26.1% and an output P1dB of 22 dBm with a PAE of 21.8% in high-power mode and low-power mode, respectively, while occupying only a 1.5-\mm^2 die area in 180-nm CMOS. In the closed-loop power-detecting mode, the PA achieves an adjacent channel leakage ratio of -22.6 dBc and an error vector magnitude of -26.9 dB at 23-dBm output power for 120-Mb/s 7.6-dB peak-to-average power-ratio 64 quadrature amplitude modulation 802.11n signals. [ABSTRACT FROM AUTHOR]

A power-scalable reconfigurable filter with in-phase/quadrature (I/Q) imbalance calibration for a multimode Global Navigation Satellite Systems (GNSS) receiver is presented. The filter is reconfigurable as either a fifth-order complex bandpass filter exhibiting a tunable intermediate frequency (4.092, 6.138, 10.23, 12.296, 13.29, 18.4, and 20.442 MHz) and bandwidth (2.2, 4.2, 8, 10, and 18 MHz) or a third-order low-pass filter with tunable bandwidth (5 and 9 MHz). A flexible current-reuse operational amplifier with a power-scaling technique is proposed to lower the power consumption, and the image-rejection ratio is improved by almost 20 dB by introducing an I/Q imbalance calibration circuit before the filter. The filter, which was implemented in 65-nm CMOS, consumes 2.9–19.5 mW in different modes, with the I/Q calibration circuit consuming 0.9 mW. [ABSTRACT FROM PUBLISHER]

Traditional dye-sensitized solar cells (DSSC) use FTO/ITO containing expensive rare elements as electrodes, which are difficult to meet the requirements of flexibility. A new type of flexible DSSC structure with all-metal electrodes without rare elements is proposed in this paper. Firstly, a light-receiving layer was prepared outside the metal photoanode with small holes to realize the continuous oxidation-reduction reaction in the electrolyte; Secondly, the processing technology of the porous titanium dioxide (TiO2) film was analyzed. By testing the J–V characteristics, it was found that the performance is better when the heating rate is slow. Finally, the effects of different electrode material combinations were compared through experiments. Our results imply that in the case of all stainless-steel electrodes, the open-circuit voltage can reach 0.73 V, and in the case of a titanium photoanode, the photoelectric conversion efficiency can reach 3.86%. [ABSTRACT FROM AUTHOR]

To optimize the use of distributed energy, this work builds a combined cooling heating and power system (CCHP) driven by distributed energy, including three subsystems: the electricity subsystem, CCHP subsystem, and ground source heat pump (GSHP) subsystem. Then, energy, economic and environmental performance indicators are constructed using a natural gas‐driven CCHP system (NG CCHP) as the frame of reference. Thirdly, three system operation modes are put forward, including following the thermal load (FTL) mode, following the electric load (FEL) mode, and electric load combine thermal load (ECT) mode. In the meantime, three kinds of system operation modes are proposed, including optimization of energy rate (ER), total operation cost (TOC), and carbon dioxide emission reduction (CER). Finally, Shanghai World Expo is analyzed as a simulation object. The results show that the optimal target operation strategy can balance the results of different optimization by increasing the partial load rate of the gas‐steam combined cycle system and reducing the pumping ratio of the steam turbine. Compared with the NG CCHP system, the new CCHP system performs better. The sensitivity analysis shows, as the coefficient of performance of the chiller increases and the price of NG decreases, the performance of the new CCHP system will become better. [ABSTRACT FROM AUTHOR]

A self‐tuned surface acoustic wave (SAW)‐less global navigation satellite system (GNSS) receiver is proposed. In the self‐tuning mode, the radio‐frequency amplifier (RFA) is configured as an oscillator and the receiver chain is reused to realise a simple self‐calibration. In the normal operation, the RFA works as a Q‐enhanced radio‐frequency filter to remove the out‐of‐band blockers. A gain‐irrelevant DC offset cancellation is also presented. This GNSS receiver achieves 4.8 dB noise figure and a rejection of 25.8 and 31.8 dB for DCS (1710 MHz) and PCS (1850 MHz) blockers, while consuming <5 mA current from a 1.7 V supply. [ABSTRACT FROM AUTHOR]

This paper construct a CCHP and renewable energy based hybrid energy system driven by distributed energy resources (DERs CCHP). Then, the paper constructs performance indexes from energy, economic and environment. Thirdly, the paper proposes a multi-objective optimization model for DERs CCHP system under four optimization of energy rate (ER), total operation cost (TOC), carbon dioxide emission reductions (CER) and joint optimization. Finally, Guangzhou Higher Education Mega Center (GHEMC) in China is taken as the object for comparatively analyzing the operation performance of DERs CCHP system and CCHP system driven by natural gas (NG CCHP system). Results show: Joint optimization mode could balance the results of different optimization modes. DERs CCHP system shows better operation performance. ER of ER optimization, CER optimization and joint optimization are higher than that of NG CCHP system. NPV of all optimization modes is positive, IRR are bigger than the expected yield rate. DERs CCHP system could reduce CO 2 emission by utilizing wind energy and solar energy to replace NG. The sensitivity analysis indicates the performance of the DERs CCHP system will become better with the increase of chiller COP, decrease of NG price and wind-photovoltaic equipment cost. [ABSTRACT FROM AUTHOR]