Green Power Supply Research Articles

Techno-economic analysis of deploying a short or mixed energy storage strategy in a 100 % green power grid

A fully decarbonised electricity grid with extensively deployed renewable systems is a fundamental step in transitioning to a net-zero world. Unlike fossil energy, renewable energy systems are subject to meteorological intermittency. However, few studies have investigated the techno-economic performance of integrating short- and promising long-duration energy storage into a 100 % renewable energy grid to balance short-term and inter-seasonal demand.This research developed an economic model to investigate the techno-economic performance of standalone and combined energy storage solutions for a fully green grid in three defined scenarios. Lithium-ion batteries (Li-ion), hydrogen, and electrical thermal energy storage (ETES) were selected as promising storage technologies due to their maturity, commercial availability, and scalability. The three examined scenarios are: 1) Li-ion battery only, 2) Li-ion battery with ETES, and 3) Li-ion battery with hydrogen. The research aims to determine whether combining long-duration energy storage (e.g., ETES and hydrogen) with Li-ion batteries offers greater economic and technical benefits, resulting in a more affordable, resilient, and secure power supply.The results show that the Li-ion battery only scenario (Scenario 1) requires a capacity of 234,956 MWh. Adding ETES and hydrogen reduces this capacity to 53,304 MWh (Scenario 2) and 7020 MWh (Scenario 3). The addition of ETES and hydrogen improves power supply flexibility, increasing the proportion of generated electricity used to meet demand from 32.7 % in Scenario 1 to 41.2 % and 52.3 % in Scenarios 2 and 3, respectively. These technologies also help avoid electricity deficits, reduce the loss of power probability (LOPP), and lower the cost of electricity supply losses from $8365 million in Scenario 1 to $1793 million in Scenario 2 and only $4 million in Scenario 3. Power delivery costs decrease from $99.5/MWh in Scenario 1 to $77.6/MWh and $76.6/MWh in Scenarios 2 and 3, respectively. The research concludes with four policy recommendations to advance long-duration energy storage and transition to a fully green power supply system.

Study on green power supply modes for heavy load in remote areas

In this study, the present situation and characteristics of power supply in remote areas are summarized. By studying the cases of power supply projects in remote areas, the experience is analyzed and described, and the applicability of related technologies, such as grid-forming storage and power load management, is studied, including grid-connection technologies, such as grid-forming converters and power load management. On this basis, three power-supply modes were proposed. The application scenarios and advantages of the three modes were compared and analyzed. Based on the local development situation, the temporal sequences of the three schemes are described, and a case study was conducted. The study of the heavy-load power supply mode in remote areas contributes to solving the problem of heavy-load green power consumption in remote areas and promoting the further development of renewable energy.

A wind-driven rotating micro-hybrid nanogenerator for powering environmental monitoring devices based on a brush-type triboelectric unit

Abstract The rapid rise of the IoT (Internet of Things) technology and microelectronics technology has promoted the development of sensors to ultra-low power consumption. However, for conventional wired power supply and chemical battery power supply, there are difficulties in wiring, inconvenient battery replacement and environmental pollution problems, so there is an urgent need for a green power supply. The low cost and simple structure of TENG (Triboelectric nanogenerator) have attracted much attention from researchers. However, for most of the existing TENG, there are some problems such as narrow operating frequency range, short life of TENG, insufficient traditional flexible friction contact, and serious wear of rigid friction contact. Herein, we propose a rotary brush-type triboelectric-electromagnetic hybrid nanogenerator. Through the experimental tests, the TENG part can output the maximum power of 0.88 mW under the external load of 8 MΩ at 400 rpm (wind speed of about 8.3 m/s). The EMG (Electromagnetic Generator) part can output the maximum power of 15.5 mW under external load of 360 Ω. The LED lighting test proves that the generator broadens the frequency of energy harvesting. In the capacitor charging test, the high voltage characteristics of tribological power generation play the advantages of continuous voltage boost, and the high current characteristics of electromagnetic power generation play the advantages of high power. The hybrid nanogenerator can realize the wind energy harvesting under the broadband wind speed of 3 m/s~14 m/s. At a wind speed of 5.6 m/s, the hybrid nanogenerator ran at about 225 rpm and successfully powered the anemometer after 21 s. After 80,000 cycles, the maximum open circuit voltage only drops by 5.6%, which proves that the rotary TENG unit has a long generation life, and can realize the harvesting of wind energy and the power supply of wind speed sensor.

Characterization of Temperature and Strain Changes in Lithium-Ion Batteries Based on a Hinged Differential Lever Sensitization Fiber Bragg Grating Strain-Temperature Simultaneous-Measurement Sensor.

Li-ion batteries are expected to become the mainstream devices for green energy storage or power supply in the future due to their advantages of high energy and power density and long cycle life. Monitoring the temperature and strain change characteristics of Li-ion batteries during operation is conducive to judging their safety performance. The hinged differential lever sensitization structure was used for strain sensitization in the design of an FBG sensor, which also allowed the simultaneous measurement of strain and temperature. The temperature and strain variation characteristics on the surface of a Li-ion soft-packed battery were measured using the des.igned sensor. This report found that the charging and discharging processes of Li-ion batteries are both exothermic processes, and exothermic heat release is greater when discharging than when charging. The strain on the surface of Li-ion batteries depends on electrochemical changes and thermal expansion effects during the charge and discharge processes. The charging process showed an increasing strain, and the discharging process showed a decreasing strain. Thermal expansion was found to be the primary cause of strain at high rates.

Technology Focus: Production and Facilities (December 2023)

It seems that it has been a very productive period for production and facilities. I reviewed a significant number of abstracts on such an interesting variety of topics—new technology developments down- and midstream, improvements in corrosion detection and prediction, new systems for emulsion monitoring, and even downhole drones, as well as several optimization works using artificial intelligence and machine learning, for quality and control. In the materials-science aspect, composite and nonmetallic materials continue to be significantly researched, as well as additive manufacturing for fast replacement of parts. I also reviewed abstracts on new materials development for downstream applications, such as dielectric sealants and dissolvable rubbers. Some fundamental research on emulsion stability was also present, as well as new emulsion monitoring systems based on microwave, acoustic, and capacitance measurements. In the area of equipment reliability, a common trend is using digital methods on historical data for prediction of equipment failure or corrosion vulnerability. There were also inspection developments such as the use of chemical tracers to identify the location of equipment failure downstream. A couple of works in this area are suggested in paper SPE 205687, which provides an example of deep learning used for intelligent identification of equipment status, and paper SPE 205056, which is a more-fundamental work on corrosion-prediction models. My attention was particularly drawn to environmentally oriented submissions this year. Energy integration continues to be a topic of interest, with geothermal and even green hydrogen being considered for energy generation in production facilities, especially in remote locations. An example of an interesting energy integration viability study can be found in paper SPE 204551. Another relevant aspect addressed was waste management, with submissions regarding abandoned wells management and waste disposal. A very thorough review on how to deal with produced solids can be found in paper SPE 210003, which clearly explains all stages of handling, from separation to disposal, with case studies as examples. An interesting work, paper SPE 213000, combines two issues: the disposal of wind-turbine waste and the use of abandoned wells. Because of the toxicity of wind-turbine blades, abandoned wells and cement coprocessing are considered as disposal options. It is quite interesting how costs and emissions were carefully analyzed in this study. Paper SPE 211932 caught my attention for its social and economic impact. This work presents the use of modular refineries as an alternative, cheaper solution to increase refining capabilities. Many developing nations produce more oil than their internal market consumes but still need to import large quantities of refined products. This work points this out as an anomaly. While some refining companies may profit from this, deep social impacts are caused by the increased gas prices in nations that are petroleum-rich. It is nice to see developments in our field that can contribute to less social inequality in the world. Recommended additional reading at OnePetro: www.onepetro.org. SPE 205056 Possible Missing Link in CO2 Corrosion Prediction by Yves Gunaltun, Retired SPE 205687 A Deep-Learning Model To Intelligently Identify the Working Status of Screw Pumps for Oil Well Lifting by Zhen Wang, Luming Oil and Gas Exploration and Development, et al. SPE 204551 Challenges and Opportunities for Green Hydrogen Power Supply in Oil and Gas Remote Facilities by Salvador Alejandro Ruvalcaba Velarde, Heriot-Watt University

Kinetic Study of Carbon Deposition in Solid Oxide Fuel Cells (SOFCs)

Owing to many irreplaceable advances, solid oxide fuel cells (SOFCs) have a promising and competitive potential in the application of green power supply and greenhouse gas reduction. Especially the utilization of biomass-derived syngas shows a high efficiency potential for the overall system. However, carbon deposition at the anode is a major challenge for the practical application. Once carbon deposited at the anode, the degradation of SOFC performance is permanent and irreversible to a certain extent. The carbon deposition is closely associated with the inner temperature distribution and fuel gas composition within the SOFCs, which is determined by complex chemical and electrochemical reactions. In this study, competing kinetic rates for carbon deposition and regasification are analyzed based on CFD methods for typical biomass-derived syngas compositions. Based on this method, reasonable operating conditions and flow field configuration can be recommended, which reduce the kinetic rate of carbon deposition at the SOFC anode. It is also worth mentioning that the specific anode area where carbon deposition occurs firstly will be detected numerically under different fuel gas components, operating temperatures and flow filed configurations. In summary, an effective method is provided to reduce the carbon deposition at the anode and improve the life expectancy of SOFCs, which is meaningful for SOFC design and operation in practical applications.

Review on key technologies of green power supply for port microgrid

Complex Engineering Systems are generally represented in terms of a set of interconnected systems that their collective/global behaviors/properties are somewhat difficult to be predicted or managed. The context of complex engineering systems is mainly concerned with developing multi-component engineering systems, designs, or algorithms to exploit those unpredictable collective/global behaviors/properties. Complexity in Engineering Systems is in general manifested in component, product, system, interconnections of interacting subsystems or multidisciplinary system designs. In a broad sense, complexity is related to the expected amount of information may need to describe a dynamical system.

Influencing factors of the high-quality economic development in China based on LASSO model

This paper constructs an index system for high-quality economic development in China from four dimensions: economic system, social system, environment system, and power system. The LASSO method was presented as screen indicators, then we use the panel fixed effect model to investigate the specific impact of key factors on high-quality economic development. The results indicate that: (1) Innovation-driven, infrastructure construction, green technology development, power supply, and efficient utilization of electrical equipment are the most important influencing factors to promote high-quality economic development. (2) Increasing financial expenditures for pollution prevention and control and strengthening the application of green technology will help to adjust the economic structure. (3) Building a complete green energy system will be an essential part of high-quality economic development. On this basis, heterogeneity analysis is carried out according to regional economic differences and power supply and demand positioning. These findings have great significance in high-quality economic development of China.

Output analysis and capacity configuration of green backup power supply in data center

The backup power supply ensures the stability and reliability of the power supply for a data center. Starting from green backup power supply, this paper studies the selection and configuration method of energy storage mode of backup power supply according to the backup power demand of data center and peak regulation demand of power grid, and analyzes different forms of green backup power supply and the output characteristics of hydrogen fuel cell. Aiming at improving the economy of green backup power assisted peak regulation, the capacity configuration principles of hydrogen energy storage and electrochemical energy storage technology are clarified, and then the capacity configuration of standby power in data center is simulated. The results show that the capacity configuration requirements of lithium battery, fuel cell and hydrogen storage tank corresponding to engineering life can be obtained through algorithm optimization.

Self-powered and multi-mode flexible sensing film with patterned conductive network for wireless monitoring in healthcare

The flexible and multi-functional strain sensors have attracted extensive research attention due to their promising applications in various wearable electronics. However, it remains a huge challenge to design and fabricate the self-powered flexible sensing micro-system based on a single multifunctional material to relieve the dependence on external rigid and heavy battery. Herein, a self-powered and multi-mode flexible sensing system integrated with triboelectric nanogenerator (TENG), flexible solid-state supercapacitors (FSSC) and strain sensor is developed based on thermoplastic polyurethane film with asymmetric and cross conductive networks through a facile screen printing process. The unique conductive network endows the prepared strain sensor with an independent anisotropic response to the strain applied in different directions. The TENG in single-electrode mode is presented to generate electricity from ubiquitously bio-mechanical energy and stored it in the FSSC immediately, realizing continuous green power supply for the sensor. As proof-of-concept, an all-in-one smart device consisting of energy supply and sensing module is constructed, demonstrating the great convenience and feasibility for practical application in sustainable wearable electronics. Benefiting from the excellent comprehensive sensing performance, the wireless wearable device assembled by the prepared sensor exhibits excellent detection and recognition for various human motion, expressions, phonation, and physiological signal, revealing the broad potential applications in rehabilitation training, human-machine interaction and medical diagnosis. This work proposes an innovative and scalable approach to manufacture multifunctional micro-systems, which will bring new vitality and more possibilities to a new generation of wearable electronics.

Offshore Wind-to-Hydrogen Production Plant Integrated with an Innovative Hydro-Pneumatic Energy Storage Device

One of the main technical challenges of wind-to-hydrogen production plants is to couple intermittent and variable renewable power sources, such as wind turbines, with an electrolyser. Most hydrogen production concepts rely on electrical storage to smoothen the power input to the electrolyser. In this study, the use of a hydro-pneumatic energy storage system is proposed as an interface between the green, fluctuating electricity supply and the electrolyser. The performance of the proposed solution is analysed and compared to that of a conventional offshore wind-to-hydrogen production plant in order to identify potential advantages and drawbacks. The results of the simulations show that the FLASC energy storage system provides a stabilized, yet green power supply. Short-term fluctuations of the power input to the electrolyser can be avoided. A 70% reduction of the On/Off cycles can be obtained. Moreover, if compared to an offshore wind-to-hydrogen production plant with no storage there is no substantial difference in terms of hydrogen production observed over the analysed period of one year in spite of a 70% round-trip efficiency of the energy storage device.

Cellulose melt processing assisted by small biomass molecule to fabricate recyclable ionogels for versatile stretchable triboelectric nanogenerators

Ionogels are promising electrode materials of stretchable triboelectric nanogenerators (TENG). However, the development of ionogel materials that simultaneously meet the requirements of green start feedstock, simple fabrication, multifunction, and recyclable feature remains a challenging issue. Here, we try to address this by adopting novel melt-polymerization of hydroxypropyl cellulose (HPC) in molten α-lipoic acid (LA) liquid. This strategy is extremely simple, facile, based on biomass molecules, and offers a promising methodology to completely melt processing of cellulose materials. The HPC chains successfully forms the double-network structure with LA poly(disulfides) chains by multiple hydrogen bonding interactions. As result, the integrated merits of high transparency, high strength, fine stretchability, moderate conductivity, healability, ultraviolet resistance, thermal stability, strain-sensitivity, and full recyclability are realized in the obtained ionogels. Encouraging by these features, a versatile triboelectric nanogenerator (I-TENG) (3 cm × 3 cm) is fabricated using ionogels as functional electrodes. This nanogenerator can harvest biomechanical energies and convert them into electrical outputs of 80 V, 2 µA, 27 nC, and the max power density of 67.9 mW m−2 at a fixed frequency of 3 Hz, respectively. Beside transparent characteristic, this nanogenerator is able to maintain good energy harvesting performance after stretching, high temperature storage, long-term operation, mechanical damage, and even recycling. Notably, the I-TENG can not only work as green power supply to drive small electronics, but also as self-powered sensors to distinguish human motions and English letters.

Efficient Blockchain-Enabled Large Scale Parked Vehicular Computing With Green Energy Supply

While the vehicular network enables geographically distributed cooperative computation, its mature implementation has long been constrained due to the lack of an effective management platform. In this paper, employing the security and privacy attributes of blockchain, we propose a novel Blockchain-enabled Large-scale Parked Vehicular Computing (BLPVC) architecture to utilize the potential solar energy and vehicular computational resources in the outdoor parking lot. However, the uneven green power supply and random arrival time of electric vehicles compose the highly complex environment. Accordingly, in this paper, to handle the efficient utilization of the distributed resources by blockchain technology, we propose an integrated optimization framework which leverages the green energy utilization and service latency limit among the processes of block generation, task computing, and communication, whereas such a design leads to the mixed-timescale stochastic optimization problem. To this end, corresponding to the dynamic solar energy arrival, we propose a shaped deep deterministic policy gradient (DDPG) algorithm to accelerate the learning rate of computational frequency control in the short-term stage; while in the long-term stage, for the mixed-integer programming (MIP) of task offloading and blockchain parameters adjustment, a series of transformation is employed to preserve convexity. Finally, experiments are carried out on Python demonstrating that the proposed scheme achieves a balanced performance between service latency and distributed resources, while the battery depreciation cost is heavily reduced.

Optimal Synergy between Photovoltaic Panels and Hydrogen Fuel Cells for Green Power Supply of a Green Building—A Case Study

Alternative energy resources have a significant function in the performance and decarbonization of power engendering schemes in the building application domain. Additionally, “green buildings” play a special role in reducing energy consumption and minimizing CO2 emissions in the building sector. This research article analyzes the performance of alternative primary energy sources (sun and hydrogen) integrated into a hybrid photovoltaic panel/fuel cell system, and their optimal synergy to provide green energy for a green building. The study addresses the future hydrogen-based economy, which involves the supply of hydrogen as the fuel needed to provide fuel cell energy through a power distribution infrastructure. The objective of this research is to use fuel cells in this field and to investigate their use as a green building energy supply through a hybrid electricity generation system, which also uses photovoltaic panels to convert solar energy. The fuel cell hydrogen is supplied through a distribution network in which hydrogen production is outsourced and independent of the power generation system. The case study creates virtual operating conditions for this type of hybrid energy system and simulates its operation over a one-year period. The goal is to demonstrate the role and utility of fuel cells in virtual conditions by analyzing energy and economic performance indicators, as well as carbon dioxide emissions. The case study analyzes the optimal synergy between photovoltaic panels and fuel cells for the power supply of a green building. In the simulation, an optimally configured hybrid system supplies 100% of the energy to the green building while generating carbon dioxide emissions equal to 11.72% of the average value calculated for a conventional energy system providing similar energy to a standard residential building. Photovoltaic panels account for 32% of the required annual electricity production, and the fuel cells generate 68% of the total annual energy output of the system.

A hand-driven portable triboelectric nanogenerator using whirligig spinning dynamics

Abstract Pervasive and portable energy solutions are highly desired in the era of Internet of Things for powering wide-range distributed electronics. Human body contains renewable biomechanical energy sources, which could be harnessed for sustainable electricity generation as portable power sources for wearable bioelectronics. Herein, we propose an ultralow-cost, efficient, portable hand-driven triboelectric nanogenerator (HD-TENG) enabled by whirligig spinning to harvest energy from low-frequency and linear human biomechanical motions. Remarkably, the operating HD-TENG could easily achieve a rotational speed of over 10,000 rpm with a gentle hand stretching in a linear and periodic manner. The reported HD-TENG was demonstrated to charge a 220 μ F commercial capacitor up to 3 V in less than 80 s, and continuously drive a smart bracelet for health monitoring, and a portable MPEG-1 audio layer III for music playing. With a collection features of high output power, light weight, excellent portability, ease of transport, cost-effectiveness, and environmental friendliness, the ingeniously designed HD-TENG represents a convenient green power supply approach for wearable bioelectronics in the era of Internet of Things.

Evaluation and Control Strategy of the Regulation Capacity of Electric Heating Load

In face of increasingly severe environmental problems, green and low-carbon power supply has become an important trend of current development. At present, the smart grid which will respond to the demand has improved the interaction between current users and the grid. In addition, electric heating and solar power generation and other renewable power generation methods are promoted in north China. Electric heating is a flexible and regulatable load; when it reaches a certain scale, it is bound to become an objective demand response resource in power grid operation, so it is of great practical significance to explore the evaluation of the regulation capacity of electric heating load.

Experimental Research on A New Type of Floating Breakwater for Wave-Absorbing and Energy-Capturing

To avoid the damage caused by big wind and wave in cage culture, and to solve the problem of energy supply faced by automatic breeding equipment, a new type of floating breakwater, named as Savonius double buoy breakwater (SDBB), is proposed in the paper. The floating breakwater is composed of HDPE cylindrical double buoys and horizontal axis Savonius rotors, and has the functions of wave-absorbing and energy-capturing. Based on the linear wave theory and energy conservation law, the Fourier Transform was applied to separate the two-dimensional wave frequency domain, and the energy captured by the rotors and absorbed by the floating breakwater were calculated. Experiments were conducted in a two-dimensional wave-making flume, and the transmitted waves at different wave heights and periods, the tension of mooring lines, and the rotational torque exerted on the Savonius rotor were measured. A series of performance comparison tests were also performed on the new floating breakwater and the traditional double-floating breakwater. Results show that the new floating breakwater is better than the traditional one in terms of reducing wave transmittance, and the combination of the floating breakwater with Savonius rotors can provide for marine aquaculture equipments with green power supply to a certain degree of self-sufficiency.

Sustainable and high-efficiency green electrical discharge machining milling method

Conventional electrical discharge machining (EDM) milling methods have some disadvantages when used to machine difficult-to-cut materials, including low machining efficiency, high energy consumption, severe electrode wear, and poor processing environments. In this paper, a sustainable and high-efficiency EDM milling method is proposed for solving the above problems. A high-efficiency green pulse power supply with high energy is designed and different environmentally friendly working fluids are used for machining experiments. The energy utilization rate, environmental performance, and machining performance under different conditions of this new method are studied. The results show that the proposed method presents high machining efficiency, low energy consumption, mild electrode wear, and environmentally friendly features. The material removal rate can reach 900.66 mm3/min and the relative electrode wear rate is 1.20% when machining the 17-4 PH stainless steel workpiece. It is found that the new pulse power supply increases the energy utilization rate by more than 200%. Compared with the conventional EDM milling methods, the proposed method can meet the requirements of energy-saving and sustainable production.

Analysis on Demand and Development Direction of Smart Grid under the Background of Two-network Convergence

With regard to development strategy of “two networks integration”, based on improvement of power supply capacity, power supply security and reliability, fault response, information collection capability as well as improvement, intelligence, integration and automation upgrade on real-time monitoring capability, “two networks integration” planning strategy and implementation plan, such as planning for distribution network, distribution itself, ubiquitous power Internet of Things, are made to greatly improve overall capacity of distribution network, which further provides reference for similar projects, such as high-quality, stable, efficient and green power supply.

Electrode selection rules for enhancing the performance of triboelectric nanogenerators and the role of few-layers graphene

The development of portable and wearable electronics requiring only few tens of microwatts to operate fosters the search for low power energy sources. Moreover, the fast-growing demand for new sustainable energy has raised the interest in energy harvesters able to convert mechanical energy into electrical power. Triboelectric nanogenerators (TENGs) can provide such green power supply. Recent developments in TENGs technology show that they can be used in different applications ranging from wearable self-powered sensors to wind and sea wave energy harvesting. In spite of the wide number of TENGs developed so far, an in depth understanding of their working principle is still missing. In this work, we highlight the fundamental role played by the interface between the triboelectric material and the electrode collector in contributing to the TENG's power generation. We show that by simply replacing the 'standard' gold electrodes with flexible few layer graphene electrodes in TENGs operating in vertical contact mode, a 26-fold increase in power density is achieved. Here, we elucidate the main mechanism at the base of such boost in power output, describing guidelines for the combination of electrode and triboelectric materials to optimize the mechanical energy conversion efficiency in TENGs.