Wind Power Projects Research Articles

Influence of Pile-Soil Interaction on Dynamic Properties and Response of Offshore Wind Turbine with Monopile Foundation in Sand Site

In this study, a sophisticated 3D finite element model of NREL 5MW wind turbine (WT) superstructure is developed using Abaqus, which includes necessary functional features, such as rotor rotation, drivetrain, pitch, servo-control, etc. A multi-step validation process has been conducted in order to verify the reliability of the blade, the Rotor-Nacelle Assembly (RNA) and the entire WT model. In the time domain, a software framework of ABA-OWT is developed for the dynamic analysis of offshore wind turbine (OWT) based on the Abaqus WT structure model and FAST submodules. The framework is capable of computing wind loads, wave loads, and servo-control commands in a fully coupled way. The pile-soil interaction (PSI) is modeled by nonlinear p-y, t-z and Q-z springs and the dashpots parallel with them. A typical sandy site is considered, while several identical analyses are performed for both numerical models including fixed base and PSI. After calculating the eigenvalues of the WT structure and analyzing its dynamic response to the combined action of wind and wave, three representative wind-wave load cases are chosen for subsequent seismic response study. The important conclusions are as follows. Firstly, the PSI reduces the natural frequencies of FA1, SS1 and FA2 by about 12% and SS2 by 23.5%. Secondly, under the combined action of wind and wave, the PSI significantly increases the tower-top peak motion responses in normal operating cases, but its influence on the mudline peak internal force responses is almost negligible; For parking cases, the PSI dramatically enlarges the peaks of the tower-top motion responses and the mudline bending moment, and the effect of PSI on the structural peak responses in parking cases is greater than that in normal operating cases. Finally, under the conjoint action of wind, wave and seismic, the PSI increases the tower-top peak motion responses and reduce the mudline peak internal force responses, and because of the aeroelastic effects, the influence of PSI on the structural peak responses in normal operating cases is always the smallest. In a word, the PSI has a remarkable impact on the natural frequency, dynamic response and seismic response of offshore wind turbine (OWT) with monopile foundation, which should be considered in a reasonable way in the practical offshore wind power project.

Optimal Coordinated Frequency Regulation of Renewable Energy Systems via an Equilibrium Optimizer

With the urgency of environmental protection, wind power and photovoltaic (PV) projects are continued to be implemented, and the proportion of renewable energy in the power grid will be higher and higher. Therefore, wind power and PV also began to participate in the regional power grid frequency regulation (FR) and have gradually replaced the role of thermal power units in the power grid. To study the characteristics of renewable energy in frequency modulation, an automatic generation control (AGC) model of wind power and photovoltaic participating in the power grid FR is established. At the same time, an equilibrium optimization is proposed to allocate the total power in real-time so as to improve the FR performance by quickly obtaining the optimal power distribution scheme. The simulation results of the proposed model show that the proposed method is feasible. At the same time, the proposed method is compared with the genetic algorithm (GA), which proves the superiority of the proposed method.

Energy, exergy, economic, environmental, advanced exergy and exergoeconomic (extended exergy) analysis of hybrid wind-solar power plant

Aiming to net-zero emissions, hybrid power generation through renewable means has gained substantial attention across the globe. Considering the stochastic nature of renewable energy resources, a comprehensive performance assessment is a must prior to project development. Present work is a novel multidimensional 6E analysis (energy, exergy, economic, environmental, advanced exergy, and exergoeconomic) to evaluate the performance of hybrid wind-solar energy systems. The analysis is performed using long-tern (41 years) high-resolution ERA5 reanalysis resource data and the mathematical modeling by means of MATLAB R2018a computation software. The long-term data facilitates reliable and precise predictions of resource availability, power generation, and system performance during the lifespan of the project. The performance of HWSES in terms of capacity factor and exergy efficiency is computed to be 9.6–35.5% and 4.7–10.4% respectively, whereas the extended exergy efficiency lies in the range of 3.39–5.79%. Hybridizing wind power projects with solar power enhances the overall system capacity factor, exergy efficiency, and extended exergy efficiency by 3.46%, 5.12%, and 2.87% respectively. Hence, the hybridization leads to superior year-round system performance with smaller power fluctuations than the standalone systems. Further, wind, solar and hybrid systems would annually reduce the Specific Emission Reduction of 1128 tone/kW, 1685 tone/kW, and 1407tone/kW respectively. The present research will be helpful to the policy-makers and the project developers in the project feasibility study of hybrid energy systems.

Analysis of the Dynamic Characteristics of the Top Flange Pile Driving Process of a Novel Monopile Foundation without a Transition Section

As the most widely used foundation type, the pile-driving capacity of large-diameter monopile foundations and the hammer force of pile top flanges is increasing, as are the stress and strain of traditional flange structures under the resistance to the cyclic impact load of pile hammers. This paper conducts an empirical study on the Rudong 150 MW offshore wind farm project in Longyuan, Jiangsu Province. The numerical simulation and calculation method of large-diameter pile fatigue damage is mastered and proposed, and a simulation analysis and comparison is conducted, as is an analysis of the sensitivity and feedback of the key software parameters. Based on the results of the above analysis, a pile simulation analysis of the offshore wind power projects under construction and those that are about to be started is performed. The pile hammer stroke energy and pile top hammer stroke process curve are extracted. According to the time range curve of limit and hammer stroke forces, the flange limit stress and distribution of the pile roof are simulated. Combined with the process characteristics of large-diameter pile sinking and analysis in the case of high hammer energy and high acceleration, the effect of the impact on the sensor is discussed. The results show that the instantaneous loading analysis could load at the flange of the pile, the maximum instantaneous stress was above 500 MPa, and the final maximum stress was approximately 307 MPa. Different loading methods vary greatly in the calculation results of the structure, so choosing the appropriate loading simulation method is key to pile sinking analysis.

Wind power generation and appropriate feed-in-tariff under limited wind resource in central Thailand

The objective of this paper is to assess the wind energy resource in the central region of Thailand for wind power generation, along with analyzing the economic feasibility and appropriate feed-in-tariff (FIT) of a proposed 15 MW wind power plant. A microscale wind resource map was created using measured wind data, a computational fluid dynamics wind flow modeling and high-resolution topography databases. Five utility-scale wind turbine generators (WTG), with hub heights ranging from 80 to 120 m above ground level (agl), were used to estimate the annual energy production (AEP). Considering the available wind resource, the most appropriate WTG was identified, and a wind power plant layout was achieved to maximize the AEP as well as minimizing the wake losses. The maximum net AEP, capacity factor (CF), %AEP improvement, %wake loss reduction, and CO2eq emission avoidance were also analyzed. Several financial indices and the levelized cost of energy (LCOE) were analyzed on the basis of a cost–benefit analysis. The economic sensitivity of the costs was used to determine the most appropriate FIT for the project. Results reveal that the mean annual wind speed at 120 m agl in the central region of Thailand reaches 5.8 m/s. The net AEP, CF, %AEP improvement, %wake loss, and CO2eq emission avoidance for a 15 MW wind power plant are estimated at 41 GWh/year, 30%, 6%, 10% and 231 ktonnes CO2eq/year, respectively. The LCOE for a base case scenario is estimated at 0.093 US$/kWh, with a FIT of 0.195 US$/kWh. Finally, the results of this work can be used as guidelines for wind power project development in the central region of Thailand and in other regions of the world where the wind resource is low to moderate under current existing WTG technology.

Energy justice issues in renewable energy megaprojects: implications for a socioeconomic evaluation of megaprojects

PurposeThe purpose of this paper is to investigate and discuss stakeholder issues faced by renewable energy megaprojects and in particular solar and wind power projects and their relevance to socioeconomic evaluation of megaprojects.Design/methodology/approachThe paper uses secondary data collected from the recent literature published on stakeholder issues face by mega solar and wind power energy generation projects around the world. The issues are then analysed across specific challenges in five continents where these projects are being developed. The paper then focuses on the literature on energy justice to elaborate the type of issues being faced by renewable energy megaprojects contributing to the achievement of UN Sustainable Goal 7 and their impact on vulnerable communities where these projects are situated.FindingsRenewable energy megaprojects are rarely discussed in the project management literature on megaprojects despite their size and importance in delivering sustainable development goals. While these projects provide social benefits they also create issues of justice due to their impact of vulnerable populations living is locations where these projects are situated. The justice issues faced include procedural justice, distributive justice, recognition inequalities. The type of justice issues was found to vary intensity in the developed, emerging and developing economies. It was found that nonprofit organisations are embarking on strategies to alleviate energy justice issues in innovative ways. It was also found that, in some instances, smaller local projects developed with community participation could actually contribute more equitable to the UN sustainable development goals avoiding the justice issues posed by mega renewable energy projects.Research limitations/implicationsThe research uses secondary data due to which it is difficult to present a more comprehensive picture of stakeholder issues involving renewable energy megaprojects. The justice issues revealed through thesis paper with renewable energy megaprojects are also present in conventional megaprojects which have not been discussed in the project management literature. Post-COVID-19 these justice issues are likely to become mor prevalent due to the pandemic's impact on vulnerable population exacerbating the issues and increasing their severity on these populations. Therefore it is becoming even more critical to take these into account while developing renewable energy megaprojects.Practical implicationsProper identification and response to energy justice issues can help in alleviating stakeholder issues in renewable energy megaprojects.Social implicationsContributes to the equitable achievement of the United Nations Sustainable Development Goal 7.Originality/valueThis paper addresses a gap in the project management literature on the exploration of stakeholder issues on renewable energy megaprojects. It also brings out the importance of justice issues which can assist in expanding stakeholders issues faced by megaprojects as these issues have not received sufficient attention in the past in the project management literature.

Feasibility study and development prospects of offshore wind power projects in Vietnam

Vietnam is a promising market for offshore wind power development because it has one of the largest wind power potentials in south-east Asia. However, some barriers such as high investment costs, complicated construction conditions and long construction time have influenced the development of offshore wind power projects; thus, there is currently only one operational offshore wind power project in Vietnam. In this paper, the economic, technical and environmental efficiency of an offshore wind power project with a capacity of 30 MW in the southern region of Vietnam is studied by using the Windpro program and the Retscreen software. The support policies of the government and obstacles in the investment process for offshore wind power projects are also analysed. The research results show that investment in the case study offshore wind power project in the southern region of Vietnam is economically feasible with the new feed-in tariff price with an internal rate of return of 18.6%, a net present value of $19 278 263, a benefit–cost number of 1.9 and a payback period of 8.3 years. However, the government needs to continue to improve support policies for offshore wind power in Vietnam, thus incentivising offshore wind farm projects that can develop more in future.

Increasing or Diversifying Risk? Tail Correlations, Transmission Flows and Prices across Wind Power Areas

As wind power costs have declined, capacity has grown quickly, often times in adjacent areas. Price and volatility risk from wind power’s intermittency can be mitigated through geographic diversification and transmission. But wind power generation has a fat-tailed and right-skewed distribution. In this article we investigate how geographic diversification of wind power and the effect of wind power on market prices varies across the distribution of production. In a case study from Denmark and Sweden, we show that during tail-end production periods, correlations between areas increase substantially as does congestion in the transmission network. This leads to highly non-linear price effects. The marginal effect of wind power on the local prices is shown to be substantially higher at the 10th decile of wind power production. This has implications for valuation models of wind power projects and for operations of electricity markets with high penetrations of wind power.

Multi-site and multi-objective optimization for wind turbines based on the design of virtual representative wind farm

The design optimization of wind turbines is an effective solution for reducing the generation cost of wind power and enhancing its market competitiveness. Because wind power projects often require a long construction period and large investment, designing a wind turbine suitable for multiple sites is economically feasible. In this study, a multi-site and multi-objective optimization framework was proposed. Based on the modified energy cost model at single wind farm level, the concept of a virtual representative wind farm (VRWF) was presented, wherein a weight calculation method to design the weights of multiple wind farms was proposed. To simultaneously maximize the annual energy production and minimize the annual production cost of the VRWF, the non-dominated sorting multi-objective harmony algorithm was improved and employed for conducting the optimization, using which the non-dominated solutions were obtained. Subsequently, the subjective and objective combined fuzzy membership function method was presented to determine the best parameters from non-dominated solutions. The proposed method was applied to a case involving three wind farms, with the results confirming its applicability. Compared with the single-site optimization, the proposed multi-site optimization reduced the overall energy cost by 0.4%, 0.8%, and 1.9%, respectively, indicating the necessity of employing multi-site and multi-objective optimization.

Chinese Overseas Finance in Renewable Energy in Argentina and Brazil: Implications for the Energy Transition

China began to accelerate the energy transition in the last decade as a strategy for rebalancing its economy and becoming a more influential actor in the global renewable energy market. This article explores to what extent Chinese investment and financing in renewable energy projects in Argentina and Brazil promote these countries' energy transition strategies and sustainable development more broadly. To approach this question, the article provides a reading of Ostrom’s postulates of the energy transition as an increasingly relevant driver of certain states’ relationships with other countries. General trajectories of Chinese investment and lending in Latin America provide a background to Chinese investment in solar and wind power projects in Argentina and Brazil. The article concludes that China’s overseas finance merges with Argentina and Brazil’s own goals regarding renewable energy deployment and discusses future challenges in the context of the COVID-19 pandemic and its aftermath.

Cost-benefit analysis of wind power integra-tion in distribution networks

The capacity of power generation note needs to be increased globally, owing to population growth and industrial revolution. The conventional power plant across the world is inadequate to satisfy growing power demand. By optimally sizing and designing the clusters of renewable energy sources such as wind, microgrid operators can economically and environmentally sustainably provide a clean power solution that can increase the supply of electricity. Wind power (WP) generation can be utilised to reduce the stress on the power plants by minimising the peak demands in constrained distribution networks. Benefits of WP include increased energy revenue, increased system reliability, investment deferment, power loss reduction, and environmental pollution reduction. These will strengthen the performance of the power system and bring economic value to society. Moreover, many challenges are considered when integrating WP into the distribution system. These include protection device miscoordination, fundamental changes in the network topology, transmission congestion, bidirectional power flow, and harmonic current injections. In this paper, the economic cost and benefit analysis of optimal integration of WP into the distribution networks is investigated through a multi-objective analytical method. The aim is to see whether investment in the WP project is economically profitable and technically viable in the distribution system. The results obtained from the study can be utilised by power system operators, planners and designers as criteria to use WP for stimulating economic development and industrial revolution and can allow independent power producers to make appropriate investment decisions.

Dynamic Fusion Simulation Method of Intertemporal Decision Preferences of Large Groups in Weak Relationships

The fusion of large group decision-making preferences is generally based on hard constraints, and the general low-consensus heterogeneous preference interaction situation of weak relationship decision-making under soft constraints has not been investigated. This study puts forward the preference connotation structure and preference attributes of the intertemporal decision-making of weak relationships groups, objective preference comparison standards between individuals, preference interaction neighborhoods between individuals, preference learning adjustment rules, and preference cycle interaction result evaluation connotations. On this basis, this research constructs a multistage and multiple-round intertemporal decision-making preference dynamic fusion theory and a method for weak relationship large groups. The simulation results verify and support the constructed preference fusion theory and method, indicating that a relatively rational interactive learning and adjustment process can improve the group decision-making performance of the key digital technology R&D team for offshore wind power project construction, operation, and maintenance and effectively improve the convergence level, convergence time, comprehensive decision-making benefits, and decision-making cognition. In the increasingly open large group intertemporal decision-making situation, these research viewpoints and conclusions will help to expand the strong relationship hypotheses of preference fusion in previous group decision-making research. The research opinions and conclusions supplement the theory and method of preference interaction fusion under soft constraints in large group decision-making.

Research on wind power project investment risk evaluation based on fuzzy-gray clustering trigonometric function

Under the goal of “Emission peak, carbon-neutral”, it has become an inevitable choice to build a new power system with new energy as the mainstay in the “14th Five-Year Plan” period. Wind power has become the hot spot of new energy development with its green, non-polluting, and renewable characteristics. In this paper, the investment risk evaluation index system of wind power projects is constructed for the investment risk characteristics of wind power projects, and the fuzzy-gray clustering trigonometric function comprehensive evaluation model is used to study the investment risk of wind power projects in China. The research results show that the risk evaluation index system constructed in this paper is reasonable, the evaluation results are consistent with the actual, and the evaluation method can be used as a reference tool for wind power project investment decisions.

The distribution of conflict and attention across energy infrastructure

AbstractAcross the world, public administration and policy decisions are related to diverse levels of conflict and attention. However, the degree and variance of conflict and attention remain largely unspecified. This article examines how types of energy infrastructure and characteristics of project location are associated with the distribution of conflict and attention around the energy infrastructure siting process. Our empirical focus is on gas pipelines, electricity transmission lines, solar power projects, and wind power projects across the United States in 2018. Primarily relying on regression analysis and interviews, this article finds differences in the distribution of conflict and attention intensity within and between these energy infrastructure types, with gas pipelines and wind power projects presenting relatively higher conflict and attention intensities. However, conflict and attention are skewed to low intensities across infrastructure types. Characteristics of project locations that are positively associated with high conflict and attention intensity include the proportion of Democratic voters and the level of urbanization in the places where projects are sited. In contrast, the proportion of Black or Hispanic residents is negatively associated with high conflict and attention intensity.

The impact of hourly pricing for renewable generation projects in Brazil

The hourly price of the Brazilian electricity market came into operation in 2021, changing the previous pricing policy that worked in a weekly basis. The impact that this change has on wind and solar generators' business may be a cause for attention, since in an hourly price scenario with collateral and daily financial settlements, wind and solar power generators may be subject to a large financial exposure into the short-term market. Thus, the present article has as its main goal the evaluation of the impact caused on the intrinsic value of wind and solar power projects with the adoption of the new hourly pricing policy in the electricity sector compared to the old weekly pricing policy. To this end, a financial economic model was developed for generic and hypothetical wind and solar farms in the Brazilian electricity sector to find its fair value operating under two different pricing scenarios. The value of these farms was also sensitized through Monte Carlo simulations, after assigning probability distributions for certain model inputs. As a result of this work, wind power projects presented a negative impact on their values and solar power plants tend to present positive results, varying according to region. However, it is also discussed that this variation caused by hourly prices is a correction to the inefficient allocation of risks that previously existed.

Wind power generation in Brazil: An overview about investment and scale analysis in 758 projects using the Levelized Cost of Energy

This paper studied 758 Brazilian wind power projects on the basis of energy auctions between 2009 and 2019 and analyzed investment and scale. It also provided an overview of the expected performance of these projects, especially in terms of costs and economic feasibility, using the Levelized Cost of Energy (LCOE). Our intention is to present results that allow us to question if the policies for this renewable energy have been effective in Brazil. The evolvement of these projects became clear in the findings, namely in the increase of capacity factors, and in the reduction in total investment and LCOE. The scale of majority of the projects are under the scale of 31 MW of installed capacity, and the projects above this threshold have lower LCOE, resulting in an inconclusive discussion if it might be seen as evidence of scale gains. The LCOE values were calculated using the two main taxation methods in Brazil, confirming the market expectations that the presumed profit method provides lower expenses than the actual profit method. The projects are expected to be in a critical economic situation, with LCOE averages being far higher than the auction price averages, raising concerns about the Brazilian renewable energy policies.

풍력발전사업의 주요 장애요인 분석과 시사점 : 풍력발전 사업주체의 관점에서

Wind power projects are hindered by various required licenses and permits, local acceptance, and grid connection. In a survey on 240 projects for which power generation business licenses were permitted, 123 projects (7,053.8 MW), 51.3% of the total, have been delayed, suspended, or stopped. Of the 79 projects classified as delayed, 33 projects (1,655.3 MW) have been suffering from regulated areas, and 34 projects (2,346.9 MW) have difficulty securing local acceptance. 11 projects (889.7 MW) have difficulties in consulting with other organizations, and 21 projects (1,623.7 MW) responded that they had been delayed due to other reasons such as not securing grid connection or disputes with other companies.<BR> To prevent delays of wind power projects, it is necessary to establish and consistently apply clear regulations and to closely review the regulations applied to wind farms before permitting power generation business licenses. In addition, developers should communicate with residents from the initial stage of the project and minimize noise and environmental and landscape damage. Distance requirements need to be adjusted based on the surrounding circumstances, and a specific power infrastructure construction plan needs to be prepared for offshore wind power projects, which are rapidly increasing.

Design and Research of Stepped Wind Turbine Foundation Structure

This paper introduces a design and research of stepped wind turbine foundation and compares it with circular spread foundation and octagonal raft foundation in engineering quantity and constructability. It shows that the stepped wind turbine foundation has clear mechanical behaviour, efficient in design and analysis. It is a good solution in terms of investment and constructability in wind power projects. Finally, a practical application of this stepped foundation design in a wind farm in Pakistan is presented, efficient construction, and good economic benefits are obtained.

Development of a 3-legged jacket substructure for installation in the southwest offshore wind farm in South Korea

A suitable substructure for Offshore Wind Turbines plays an important role since it can efficiently reduce the financial costs of wind power projects. According to the track record of the Korean offshore wind farms, the 4-Legged Jacket (4LJ) substructure is the most utilized system; however, this design is still limited, specifically in the economic aspects. Thus, this study aims to design a more cost-effective substructure to enable large-scale deployment for Korean offshore projects. To achieve this objective, the new 3-Legged Jacket (3LJ) substructures together with various bracing topological forms (i.e., Pratt, Warren, and X-bracing) are developed. Results show that under the environment loads, dynamic responses obtained from the developed 3LJs are almost independent to the loading directionality; while there is a strong polarization in the case of 4LJ. Among the three cases of the 3LJs, the X-type topological form has the highest flexural stiffness together with the largest manufacturing and fabrication costs, while the Warren bracing system reaches ultimate strength earlier than the Pratt system. Therefore, the 3LJ substructure with a Pratt bracing system is suggested as a good alternative to the existing 4LJ system for Korean offshore wind farms, with reductions of up to 21% and 25% in total weight and number of weld joints, respectively.

Spherical Fuzzy Multicriteria Decision-Making Model for Wind Turbine Supplier Selection in a Renewable Energy Project

The Vietnamese government has decided to use and promote the development of more renewable energy sources, particularly wind energy. When implementing a wind energy project, choosing a wind turbine supplier is an important decision and investors must find the optimal supplier through evaluating many qualitative and quantitative criteria that affect each other symmetrically. Therefore, the process used for selecting a wind turbine supplier in wind power projects is a multi-criteria decision-making process. Many approaches have been applied for this decision process, some of which are based on multicriteria decision-making (MCDM) methods, whether applied individually or in combination with other MCDM models. In this study, the researchers proposed a decision-making model based on spherical fuzzy sets for wind turbine supplier selection in wind power energy projects. In this paper, Vietnam is used as a case study. The recommended turbine suppliers for installations can finally be generated after the calculations in the final stage of this research. The contribution of this research is developing a fuzzy MCDM model for suitable turbine suppliers in wind power energy projects. The results of this study can be used as references for experts in deciding on a suitable wind turbine supplier in other countries as well as in other renewable energy projects.