scholarly journals A Grid for all Seasons: Enhancing the Integration of Variable Solar and Wind Power in Electricity Systems Across Africa

2021 ◽  
Author(s):  
Sebastian Sterl
Keyword(s):  
Wind Power ◽  
Large Scale ◽  
Power Grids ◽  
Solar Pv ◽  
Renewable Electricity ◽  
African Countries ◽  
Research Attention ◽  
Significant Research ◽  
Power To Gas ◽  
Electricity Access

Abstract Purpose of review This review paper assesses recent scientific findings around the integration of variable renewable electricity (VRE) sources, mostly solar PV and wind power, on power grids across Africa, in the context of expanding electricity access while ensuring low costs and reducing fossil fuel emissions. Recent findings In this context, significant research attention has been given to increased cross-border transmission infrastructure between African countries to harness the spatiotemporal complementarities between renewable electricity resources, as well as to storage options, such as battery storage and power-to-gas. Summary Much of the recent, model-based literature suggests that a combination of increased interconnections in and between Africa’s power pools, leveraging spatiotemporal complementarities between solar PV, wind and hydropower, as well as a large-scale deployment of storage options could help African countries meet their burgeoning power demand with largely decarbonized electricity supply.

The Research of Wasting Wind Power and Methods of its Consumption Based on that of Fuxin

2014 ◽  
Vol 986-987 ◽  
pp. 622-629
Author(s):  
Tian Long Shao ◽  
Jian Zhang ◽  
Xu Nan Zhao
Keyword(s):  
Power System ◽  
Wind Power ◽  
Large Scale ◽  
Clean Energy ◽  
Power Grids ◽  
Grid Structure ◽  
Wind Power Integration

As a kind of renewable clean energy, the constant access of wind power to power grids is bound to have a great impact on the power system. Based on the grid structure in Fuxin, this paper will state the difficulty of peak regulation and the matter of wasting wind power caused by the large-scale wind power integration and put forward some reasonable methods for using the wasting wind power in the heating in winter. The relevant results indicate that capacity of local consumption of wasting wind power can be improved. Under the circumstances, it can be conductive to solve the problem of wasting wind power results from the difficulty of peak regulation as well as inspire the power system planners.

scholarly journals Advanced exact synthesis of Clifford+T circuits

2020 ◽  
Vol 19 (9) ◽  
Author(s):  
Philipp Niemann ◽  
Robert Wille ◽  
Rolf Drechsler
Keyword(s):  
Large Scale ◽  
Fault Tolerant ◽  
Logic Synthesis ◽  
Research Problem ◽  
Quantum Systems ◽  
Quantum Circuits ◽  
Research Attention ◽  
Small Quantum ◽  
Significant Research ◽  
Important Research Problem

Abstract Quantum systems provide a new way of conducting computations based on the so-called qubits. Due to the potential for significant speed-ups, this field received significant research attention in recent years. The Clifford+T library is a very promising and popular gate library for these kinds of computations. Unlike other libraries considered so far, it consists of only a small number of gates for all of which robust, fault-tolerant realizations are known for many technologies that seem to be promising for large-scale quantum computing. As a consequence, (logic) synthesis of Clifford+T quantum circuits became an important research problem. However, previous work in this area has several drawbacks: Corresponding approaches are either only applicable to very small quantum systems or lead to circuits that are far from being optimal. The latter is mainly caused by the fact that current synthesis realizes the desired circuit by a local, i.e., column-wise, consideration of the underlying unitary transformation matrix to be synthesized. In this paper, we analyze the conceptual drawbacks of this approach and propose to overcome them by taking a global view of the matrices and perform a separation of concerns regarding individual synthesis steps. We precisely describe a corresponding algorithm as well as its efficient implementation on top of decision diagrams. Experimental results confirm the resulting benefits and show improvements of up to several orders of magnitudes in costs compared to previous work.

scholarly journals A New Wind Power Accommodation Strategy for Combined Heat and Power System Based on Bi-Directional Conversion

Energies ◽  
2019 ◽  
Vol 12 (13) ◽  
pp. 2458 ◽  
Author(s):  
Yanhong Luo ◽  
Zhenxing Yin ◽  
Dongsheng Yang ◽  
Bowen Zhou
Keyword(s):  
Wind Power ◽  
Thermal Energy ◽  
Northeast China ◽  
Large Scale ◽  
Fossil Fuels ◽  
Electrical Power ◽  
Combined Heat And Power ◽  
Storage Device ◽  
Reduce Emissions ◽  
Power To Gas

The extensive use of wind power can not only reduce dependence on fossil fuels, but also reduce emissions of polluted gases. However, large-scale wind power curtailments often occur in northeast China during the heat supply season, due to the fact that most of electrical demand is covered by the electrical power of the combined heat and power (CHP) during the off-peak hours. At present, for northeast China with heating demand, most of the research only focuses on how to accommodate more wind power on the spot by using one-directional conversion of the electric and thermal energy. But it is still difficult to realize the bi-directional conversion between the electro-gas or electro-thermal energy. In this paper, a combined electro-gas bi-directional conversion system (CEGBCS) is established by adding the power to gas (P2G), fuel cell and heat storage device in CHP system. This CEGBCS can not only realize bi-directional conversion of the electricity and gas, but also decouple the two operation modes of CHP unit, which greatly improve the ability of system to accommodate additional wind power. Finally, the effectiveness of the proposed CEGBCS is verified by comparing with two traditional methods.

Principles and Strategies for Promoting Coordinated Development of Wind Power and Power Grids in China

2013 ◽  
Vol 448-453 ◽  
pp. 4244-4249
Author(s):  
Qian Kun Wang ◽  
Li Ping Jiang
Keyword(s):  
Scale Development ◽  
Power System ◽  
Wind Power ◽  
Large Scale ◽  
Power Grids ◽  
Power Development ◽  
Coordinated Development ◽  
Regulatory Strategy ◽  
Incentive Policies ◽  
Wind Power Development

Based on an analysis of the misunderstanding and problems concerning wind power development, this paper summarizes the experiences of coordinated development of wind power and power grids in typical countries, proposes the principles and strategies for the coordinated development of wind power and power grids in China. Technically, bidirectional friendly technologies should be deployed to ensure the security of power system. In regulatory term, a complete and standardized regulatory strategy is key to harmonious interaction among different stakeholders concerning wind development. Incentive policies should be comprehensive, foreseeable and sustainable. Related measures and suggestions for large scale development of wind power in China are put forward.

scholarly journals Probabilistic Approaches to the Security Analysis of Smart Grid with High Wind Penetration: The Case of Jeju Island’s Power Grids

Energies ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 5785
Author(s):  
Sunoh Kim ◽  
Jin Hur
Keyword(s):  
Power Generation ◽  
Renewable Energy ◽  
Power System ◽  
Wind Power ◽  
Power Flow ◽  
Large Scale ◽  
Modeling Method ◽  
Wind Power Generation ◽  
Power Grids ◽  
Power Flow Calculation

As the importance of renewable generating resources has grown around the world, South Korea is also trying to expand the proportion of renewable generating resources in the power generation sector. Among the various renewable energy sources, wind generating resources are emerging as a key alternative to conventional power generations in the electricity sector in Korea accounted for 17.7 GW of total capacity by 2030. As wind generating resources are gradually replacing traditional generating resources, the system security and reliability are negatively affected because of the variability, due to intermittent outputs. Therefore, existing power grids will need to be correctly re-measured to cover the large scale of renewable energy, including wind generation. To expand the grid, we must understand the characteristics of renewable energy and the impact of its adoption in the grid. In this paper, we analyze various characteristics of wind power generation, and then we propose a probabilistic power output modeling method to consider the uncertainty of wind power generation. For the probabilistic approach, Monte-Carlo simulation is used in the modeling method. The modeled wind power outputs can help planning for the reinforcement and expansion of power systems to expand the capacity for large-scale renewable energy in the future. To verify the proposed method, some case studies were performed using empirical data, and probabilistic power flow calculation was performed by integrating large-scale wind power generation to the Jeju Island power system. The probabilistic method proposed in this paper can efficiently plan power system expansion and play a key strategy of evaluating the security of the power system through the results of stochastic power flow calculation.

scholarly journals Conventional generation emulation for power grids with a high penetration of wind power

Clean Energy ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 93-103
Author(s):  
Rasha El-Azab ◽  
Eslam M Wazeer ◽  
Mohamed Daowd ◽  
A M Abdel Ghany
Keyword(s):  
Wind Power ◽  
Power Plants ◽  
Large Scale ◽  
Economic Benefits ◽  
Power Grids ◽  
Maximum Point ◽  
Spinning Reserve ◽  
Thermal Plant ◽  
Point Tracking ◽  
Variable Nature

Abstract Integrating large-scale wind plants with the electricity grids has many challenges for grid operators. Besides the variability and uncertainty of wind power, coordinating between different technologies of generation in the same grid can be considered the main problem, specifically for short-term frequency stability. Therefore, a large penetration of wind power generation in modern power grids has a risky influence on the power-system frequency. Wind-generation plants have contradictory behaviour compared to classic thermal plants, especially in active generated power-shortage events due to the variable nature of wind power. Existing experience in wind plants keeps part of the available wind power unloaded, using what are known as deloading techniques. Different deloading techniques are usually applied to emulate the thermal-plant-governor function and confirm a proper spinning reserve for any active-power shortages. These techniques decrease the generated power from wind plants continuously from maximum point tracking ones. Consequently, the practical capacity, annual generated energy and economical income of wind plants are reduced. In addition, grid-protection and control sub-schemes are set and designed according to the well-known conventional responses of thermal plants, which increase the need for thermal-plant-behaviour emulation. In this paper, instead of the usual deloading methods, a supercapacitors scheme is proposed with wind turbines to emulate the response of conventional power plants. The study discusses the technical and economic benefits of the proposed addition of supercapacitors in the wind-plant-planning phase. Restricted frequency grid-code indices are selected to evaluate studied behaviours. Simulation results of the IEEE four-generation two-area system determines the effectiveness of suggested schemes technically. The System Advisor Model (SAM) program estimates the economic benefits of a typical US study case compared with the existing wind-deloading technique.

scholarly journals Sizing and operation of energy storage by Power-to-Gas and Underwater Compressed Air systems applied to offshore wind power generation

2021 ◽  
Vol 312 ◽  
pp. 01007
Author(s):  
Elena Crespi ◽  
Luca Mammoliti ◽  
Paolo Colbertaldo ◽  
Paolo Silva ◽  
Giulio Guandalini
Keyword(s):  
Energy Storage ◽  
Wind Power ◽  
Large Scale ◽  
Compressed Air ◽  
Offshore Wind ◽  
Plant Management ◽  
Economic Point ◽  
Offshore Wind Power ◽  
Market Values ◽  
Power To Gas

Among the possible solutions for large-scale renewable energy storage, Power-to-Gas (P2G) and Compressed Air Energy Storage (CAES) appear very promising. In this work, P2G and an innovative type of CAES based on underwater storage volumes (UW-CAES) are compared from a techno-economic point of view, when applied in combination with a 48 MWe offshore wind power plant, selecting an appropriate location for both high productivity and favorable seabed depth. An optimization model is employed to study the system design and operation, maximizing the lifetime plant profitability, while considering differential installation and operation costs, market values of the products (i.e., hydrogen and electricity), and technological constraints. In the current economic and technological scenario, the resulting P2G system has a nominal power equivalent to about 10% of the wind park capacity, with a small hydrogen storage buffer. On the other hand, the compressor and the turbine of the UWCAES have a nominal power close to the full wind farm capacity, and large underwater compressed air tanks are required. Both options significantly impact the wind plant management but the most beneficial applications of the two systems are different: the P2G results in a compact and flexible unit, whereas the UW-CAES is able to exploit a higher average conversion efficiency (about 80% round-trip) against a much higher installed power and investment cost. Anyway, considering the current framework, the resulting economics are still inadequate, but their competitiveness can improve compatible with the expected evolution of energy markets in the next future.

Opportunities and Challenges of Wind Power Generation in China

2014 ◽  
Vol 521 ◽  
pp. 850-854 ◽  
Author(s):  
Qian Han ◽  
Asifujiang Abudureyimu
Keyword(s):  
Wind Power ◽  
Transmission Lines ◽  
Large Scale ◽  
Manufacturing Industry ◽  
Power Transmission ◽  
Power Grid ◽  
Power Grids ◽  
Power Transmission Lines ◽  
Growth Trend ◽  
Grid Connection

China's wind power market development is set to continue its growth trend of 2011. The newly added installed capacity will be in the range of 15-18GW and is expected to reach approximately 18GW. By 2015, the installed wind power capacity will reach 100GW. The percentage of decentralized wind power will further increase, but large-scale development and land-based wind power development will still be the focus, while the ratio of decentralized wind power has the potential to reach a maximum of 30%. As power grid corporations continue to improve their ultra-high voltage power transmission lines, intelligent power grids and other infrastructure, the power grids' ability to absorb wind power electricity on a largescale, and the scale of cross-region wind power transmission will increase, with the wind power grid-connection rate also significantly increase. The wind power manufacturing industry has entered a low-profit era; competition will intensify, the market will become more mature, and wind power manufacturers will face greater market challenges. However, the wind power industry's maturity and lowering costs have enhanced wind power's competitiveness compared to traditional energy sources. Wind power has become a highstrength emerging power supply technology and its contribution to China's electricity mix will gradually increase.

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