World Wind Energy Research Articles

Efficient floating offshore wind realization: A comparative legal analysis of France, Norway and the United Kingdom

Floating offshore wind (FOW) has the potential to play a key role in many states' decarbonization policies going forward. The reason is that the majority of the world's wind energy potential is located offshore at depths where deployment of conventional bottom-fixed offshore wind turbines is not economically profitable. To realize FOW's potential as a key decarbonization technology policy makers and legislators must design legal frameworks that properly address the three main barriers to efficient deployment: (a) spatial competition, (b) need for state financing and (c) allocation of grid connection responsibilities. This article analyses and compares Norway, France and the United Kingdom's regulation of the three main barriers to efficient FOW deployment with respect of their ability to ensure efficient realisation. The article concludes with best practices and recommendation to policy makers and legislators on how to regulate the three main barriers to accomplish efficient FOW deployment.

Weydt, J. World Heritage and wind energy. Planning Protecting visual integrity in the context of the energy transition. Inspiring practices from four European countries

Reseña del libro de Weydt, J. World Heritage and wind energy. Planning Protecting visual integrity in the context of the energy transition. Inspiring practices from four European countries. Paris: UNESCO, 2021

20th World Wind Energy Conference & Exhibition (WEEC 2022)

This paper represents a preface to the Proceedings of the 20th World Wind Energy Conference & Exhibition (WEEC 2022) held in Rimini, Italy, from the 28th to the 30th of June 2022. Background information, conference resolution and the organizational structure of the meeting, program committee, and acknowledgments of the contributions of the many people who made the conference a success are presented.

Blades Interaction and Non-Stationarity of Flow in Vertical-Axial Wind Turbines

Abstract Until recently, horizontal-axial wind turbines with blades having a wing profile occupied a predominant position in the world wind energy market. But currently, vertical-axial wind units are of increasing interest and this is understandable from the point of view of their important features as: no requirements for the orientation of the wind turbine to the wind, the possibility of placing electrical and other equipment on the ground, no requirements for changes of blade chord installation angle along its length. The article discusses the aerodynamics of the vertical-axis wind turbines: the range of changes of angles of incoming flow attack on the blade, the dynamics of changes in the magnitude of the absolute speed of flow of the blade on a circular trajectory of its movement depending on the turbine rapidity, and also obtained in experiments interaction effect of the blades in the rotor. The experiments were carried out on wind turbines with original blades (basic version), which were designed to eliminate the shortcomings of low-speed rotors Savonius (low coefficient of use of wind energy) and high-speed rotors Darrieus (lack of self-start).

Optimal Control of Hydrostatic Drive Wind Turbines for Improved Power Output in Low Wind-Speed Regions

World wind energy output is steadily increasing in both production scale and capacity of harvesting wind. Hydrostatic transmission systems (HTSs) have been used mostly in offshore wind turbine applications. However, their potential has not been fully utilized in onshore wind turbines, partially due to concerns related to hydraulic losses. In our prior work, it was shown that the annual energy production from a hydrostatic wind turbine can match or exceed that of a mechanical drive wind turbine with appropriate optimal control techniques. In this paper, we present an optimal control technique that can further improve energy production of a hydrostatic wind turbine, particularly in low speed regions. Here, the overall loss equation of the HTS is developed and used as a cost function to be minimized with respect to system model dynamics. The overall loss function includes the losses due to both the aerodynamic efficiencies and the hydrostatic efficiencies of the motor and pump. A nonlinear model of HST is considered for the drive train. Optimal control law was derived by minimizing the overall loss. Both unconstrained and constrained optimization using Pontryagin’s minimum principle were utilized to derive two distinct control laws for the motor displacement. Simulation results showed that both the controllers were able to increase power output with the unconstrained optimization offering better results for the HTS wind turbine in the low speed regions (3–8 m/s).

WIND POWER: CURRENT STATE AND PERSPECTIVES

Due to the depletion of resources for traditional energy, as well as due to the gradual abandonment of nuclear power in a number of countries, the world pays great attention to energy conservation and energy efficiency, one of the main sources of which is renewable energy, which includes wind energy. Wind power is the most developed renewable energy industry (excluding hydro), which affects its economic characteristics. Thus, onshore wind power plants are characterized by one of the lowest indicators of the cost of electricity production among alternative types of generation. However, offshore wind power plants are still inferior to some types of renewable energy sources and are twice the level of traditional thermal power plants. In this article, the authors consider the state and prospects of development of the world wind energy. The distribution of installed capacity of wind power plants by regions of the world is analyzed and the shares of countries in the total installed capacity are determined. The leading countries were identified as well as the reasons for the rapid growth of wind generation in these countries along with the measures of state support. The state and prospects of wind power development in Russia are considered, and it is also noted that the Russian Federation has significant potential in the field of wind power development, which makes it possible to make optimistic forecasts regarding the provision of electricity to remote areas of Russia. The technical electric power potential of wind energy is about 17.1 TW/year, which is an order of magnitude higher than the amount of electricity generated by all power plants in the country in 2018. The scientific increment is to identify the key problems facing the domestic wind power industry.

Roe deer stress response to a wind farms: Methodological and practical implications

There is an insufficient number of field studies on the impact of wind farms on ungulates despite the rapid expansion of world wind energy. The results of previous studies suggests a possible impact of power plants, but they are divergent and do not take into account the size of wind farms. We examined the impact of wind farms on the stress levels in roe deer based on seven wind farms of various sizes (of 12–27 turbines) in eastern Poland. Fecal cortisol concentration was assessed with the ELISA method in droppings collected during the winter period. We found that the roe deer exhibited an elevated stress level in the area of larger farms, but such response was not found in the case of smaller wind farms. The roe deer were also characterized by a higher stress level in areas of wolf predation, but this factor was less important. Both the area of the farm and the number of turbines explained the phenomenon of the increased stress in the roe deer. We estimated 824 ha or 18 turbines as a threshold level of the impact of wind farms on the cortisol concentration in the roe deer. We conclude, that turbines should be concentrated in the smallest possible area. In such conditions, roe deer will probably be able to find appropriate refuges. We recommend further studies on wind farms older than 4 years and the distribution of turbines.

INTEGRATION OF WIND POWER PLANTS TO THE GRID AND REACTIVE POWER SUPPORT

The conversion of wind energy into electrical energy is one of the most environmentally sustainable methods of energy today. According to statistics published by the World Wind Energy Association, the total capacity of wind turbines installed worldwide at the beginning of 2019 exceeded 598 GW. Looking at the situation in Turkey, the number of wind power plants under operation is 180 according to published statistics at January 2019 by the Turkish Wind Energy Association. The total installed capacity of these power plants is 7369.35 MW. By the increasing of wind power capacity, the connection criteria of the power plants which are taken over to the grid become more critical. Although there are systems that are clean, renewable, and reduce external dependence on energy, power quality problems can occur in the grid connections of all wind power plants. In this respect, the grid connection criteria of wind turbines of the countries are essential. The connection requirements of wind turbines in Turkey, on April 22, 2017, revised Turkish Grid Code are determined under Appendix-18. Wind power plants connect to the grid from a medium voltage or high voltage level. At the grid connection point, there are some conditions that the plant must be met like changing wind conditions, switching, fault, etc. These requirements can be summarized as reactive power support, frequency response, contribution to the post-fault system. In this study, the reactive power capacity of a 9x3.6 MW Wind Power Plant to the grid is simulated and investigated.

Public receptivity in China towards wind energy generators: A survey experimental approach

China leads the world's wind energy market, but little has been written about public receptivity towards wind energy generators in China. To fill this gap, we pursue a survey experimental approach to examine explanations for receptivity based on evidence from OECD countries as well as the importance of public knowledge in augmenting public acceptance of wind energy generators in China. We find that Chinese respondents are sensitive to siting near their residences, to cost considerations when imposed on them directly, to wildlife externalities, and to noise from turbines. Interestingly, Chinese respondents seem to be concerned about radiation, a finding unprecedented in the literature, and are less assured by scientific assurances that radiation is not a problem. Instead, the Chinese central government is best suited to address concerns about this topic. Targeted information provision to the public can improve public knowledge about aspects of wind energy of concern. Hence, the Chinese central government can promote wind energy deployment not just because it is an authoritarian government determined to get things done, but also because it can provide relevant information to reduce potential public resistance.

Towards Improved Understanding of the Applicability of Uncertainty Forecasts in the Electric Power Industry

Around the world wind energy is starting to become a major energy provider in electricity markets, as well as participating in ancillary services markets to help maintain grid stability. The reliability of system operations and smooth integration of wind energy into electricity markets has been strongly supported by years of improvement in weather and wind power forecasting systems. Deterministic forecasts are still predominant in utility practice although truly optimal decisions and risk hedging are only possible with the adoption of uncertainty forecasts. One of the main barriers for the industrial adoption of uncertainty forecasts is the lack of understanding of its information content (e.g., its physical and statistical modeling) and standardization of uncertainty forecast products, which frequently leads to mistrust towards uncertainty forecasts and their applicability in practice. This paper aims at improving this understanding by establishing a common terminology and reviewing the methods to determine, estimate, and communicate the uncertainty in weather and wind power forecasts. This conceptual analysis of the state of the art highlights that: (i) end-users should start to look at the forecast’s properties in order to map different uncertainty representations to specific wind energy-related user requirements; (ii) a multidisciplinary team is required to foster the integration of stochastic methods in the industry sector. A set of recommendations for standardization and improved training of operators are provided along with examples of best practices.

Wind Power Potentials in Cameroon and Nigeria: Lessons from South Africa

Wind energy has seen a tremendous growth for electricity generation worldwide and reached 456 GW by the end of June 2016. According to the World Wind Energy Association, global wind power will reach 500 GW by the end of 2016. Africa is a continent that possesses huge under-utilized wind potentials. Some African countries, e.g., Morocco, Egypt, Tunisia and South Africa, have already adopted wind as an alternative power generation source in their energy mix. Among these countries, South Africa has invested heavily in wind energy with operational wind farms supplying up to 26,000 GWh annually to the national grid. However, two African countries, i.e., Cameroon and Nigeria, have vast potentials, but currently are lagging behind in wind energy development. For Nigeria, there is slow implementation of renewable energy policy, with no visible operational wind farms; while Cameroon does not have any policy plan for wind power. These issues are severely hindering both direct foreign and local investments into the electricity sector. Cameroon and Nigeria have huge wind energy potentials with similar climatic conditions and can benefit greatly from the huge success recorded in South Africa in terms of policy implementation, research, development and technical considerations. Therefore, this paper reviews the wind energy potentials, policies and future renewable energy road-maps in Cameroon and Nigeria and identifies their strength and weakness, as well as providing necessary actions for future improvement that South Africa has already adopted.

Dynamics Analysis of Wind Energy Production Development

The paper presents the analysis of the introduction experience and dynamics development of the world wind energy production. Calculated the amount of wind energy sources investments and the production capacity growth dynamics of the wind turbines. The studies have shown that the introduction dynamics of new wind energy sources is higher than any other energy source.

Effect of Tail Shapes on Yawing Performance of Micro Wind Turbine

Wind energy is one of the most widely used renewable energy resources. Large amounts of research and resources are being spent today in order to harness the energy from wind effectively. Large wind turbines are erected at windy site and delivering satisfactory performance. Small wind turbines are erected in low wind regions and are in development stage. Research activities are increasing at a significant rate in the field of small wind turbines. World wind energy association forecast considerable development in this field. To face the wind directions, small wind turbines are using mechanical systems in the form of tail. The conventional tail changes the direction of the wind turbine to accommodate the variation of the incoming direction of winds. Quick and steady response is important as per change in wind directions. It has considerable effect on the wind turbine performance. The tails are having different shapes, but literature is not available about it. Different manufacturers used different tail shapes for their model, but the effect of tail shapes has not been studied yet. Hence, it is necessary to study the effect of tail shapes on the performance of wind turbine. This paper presents the effect of tail shapes on the performance of wind turbine. In this work three different tail shapes; rectangular, trapezoidal and triangular are considered. The yawing performance for these tail shapes using CFD analysis is carried out and presented in this paper.

Examining possible relationship between carbon finance availability and growth of wind energy

This paper evaluates the possible relationship between carbon fund availability and the growth of wind energy. This has become apposite considering global quest for renewable energies as a veritable option for carbon reduction and sustainable development. Whilst some extant literature blames delay in climate policy as an obstacle to green energy, others regard carbon finance availability as a booster to renewable energy. Raging argument is that similar to any other investment, renewable energy finance availability may mar or catalyse growth in renewable energy. Consequently, in this paper, a conceptual overview of carbon finance and renewable energy is undertaken and a test of the relationship between the World Bank carbon finance availability and wind energy growth is conducted. The result indicates a significant positive relationship between World Bank carbon financing and global growth in wind energy. The paper thus concludes that aside from policy options, renewable energy financing seems to be a contributory catalyst that may spur improvement in global renewable energy. The paper highlights that achieving green economic development in developing countries would depend, not only on climate policies alone, but also on sustainable financing. Hence government and private sources of funding is very desirable in achieving global green economic development, most importantly, for developing economies. The paper thus offers a research agenda on awareness creating for local and international sources of green energy for developing countries.

Social Aspects of Wind Power Generation- A Review

Wind energy, commonly recognized to be a clean and environmentally friendly renewable energy resource that can reduce our dependency on fossil fuels, has developed rapidly in recent years. Its mature technology and comparatively low cost make it promising as an important primary energy source in the future. However, there are potential environmental impacts due to the installation and operation of the wind turbines that cannot be ignored. This paper aims to provide an overview of world wind energy scenarios, the current status of wind turbine development, development trends of offshore wind farms, and the social, environmental and climatic impact of wind farms.

Global Wind Energy Market, Industry and Economic Impacts

This paper presents the global status of wind energy in order to establish a context for understanding the contemporary wind energy industry. It is discussed wind resources worldwide with the global wind distribution and mains concerns and how wind resources worldwide are spread globally. The world wind energy market outlook is shown; especially emphasis is given on global wind energy market by production side, wind energy converters manufacturers and economic impacts from wind energy industry on economy which it is devoted special attention to the job creation by wind energy industry.

해상풍력 발전용 타워 제작시 고장력강재의 초층용접에 관한 용접특성 연구

As the world wind energy market grows rapidly, the productions of wind power generation equipment have recently increased, but manufacturers are not able meet this requirement. Particularly offshore wind energy industry is one of the most popular renewable energy sectors. To generalize welding processes, the welding automation is considered for steel structure manufacturing in offshore wind energy to get high quality and productivity. Welding technology in construction of the wind towers is depended on progress productivity. In addition, the life of wind tower structures should be considered by taking account of the natural weathering and the load it endures. The root passes are typically deposited using Gas Tungsten Arc Welding(GTAW) with a specialized backing gas shield. Not only the validation consists of welders experienced in determining the welding productivity of the baseline welding procedure, but also the standard testing required by the ASME section IX and API1104 codes, toughness testing was performed on the completed field welds. This paper presents the welding characteristics of the root-pass welding of high tensile steel in manufacturing of offshore wind tower. Based on the result from welding experiments, optimal welding conditions were selected after analyzing correlation between welding parameters(peak current, background current and wire feed rate) and back-bead geometry such as back-bead width(mm) and back-bead height performing root-pass welding experiment under various conditions. Furthermore, a response surface approach has been applied to provide an algorithm to predict an optimal welding quality.

Transient Stability Improvement of a Squirrel Cage Induction Generator in Wind Farm Using STATCOM with Supercapacitor

The increasing demand for electric power combined with depleting natural resources has led to the substantial improvements in the usage of renewable energy systems such as wind and solar especially among the developing countries. Today, wind turbine deployment shows the fastest growth both nationally and globally. Wind Electric Generators (WEG) were earlier used for isolated power supplies especially in remote locations and rural areas. In recent times, grid-connected wind electricity generation shows the highest rate of growth, achieving global annual growth rates in the order of 20–28%. According to World Wind Energy report 2010, published by World Wind Energy Association, Germany, worldwide installed capacity of wind energy reached 196630 MW out of which 37642 MW were added in 2010. Squirrel Cage Induction Generator (SCIG) is the most used generator type for WEGs One of the major issues concerning SCIG coupled to wind turbine is voltage instability problem when it is interconnected with grid. It occurs in a power system when the reactive power demand by SCIG during grid faults and heavy loading conditions is not met by the capacitor banks installed near SCWEG. This paper examines the use of STATCOM (STATic synchronous COMpensator) with Super Capacitor Energy Storage System (SCESS) to improve power quality of SCIG in the event of any unbalanced or balanced fault in the grid. Simulation is done in MATLAB SIMULINK for various conditions. Due to the fast response of supercapacitor in developing the counterbalancing electromagnetic torque, shaft acceleration is prevented and the transient stability of SCIG is increased so that it can meet the new interconnection grid code requirements. Further it is observed that the settling time of SCIG after the fault clearance is also reduced. System transients are suppressed and normal conditions are quickly restored with STATCOM and supercapacitor.

Controllable and affordable utility-scale electricity from intermittent wind resources and compressed air energy storage (CAES)

World wind energy resources are substantial, and in many areas, such as the US and northern Europe, could in theory supply all of the electricity demand. However, the remote or challenging location (i.e. offshore) and especially the intermittent character of the wind resources present formidable barriers to utilization on the scale required by a modern industrial economy. All of these technical challenges can be overcome. Long distance transmission is well understood, while offshore wind technology is being developed rapidly. Intermittent wind power can be transformed to a controllable power source with hybrid wind/compressed air energy storage (CAES) systems. The cost of electricity from such hybrid systems (including transmission) is affordable, and comparable to what users in some modern industrial economies already pay for electricity. This approach to intermittent energy integration has many advantages compared to the current strategy of forcing utilities to cope with supply uncertainty and transmission costs. Above all, it places intermittent wind on an equal technical footing with every other generation technology, including nuclear power, its most important long-term competitor.

Wind regime in the proximity of the 20 kW experimental turbine site at Nabua, Fiji

Renewable energy generated as much electric power worldwide in 2005 as one-fifth of the worlds nuclear power plants excluding large hydropower that itself accounts to 16% of world’s electricity (REN 21 2005). Renewable energy is gaining prominence in providing the world’s primary energy needs. Solar, wind, biomass, and geothermal are considered as the premier renewable energy resources that are in direct competition with the conventional fuels. The fastest growing technology has been the photovoltaic (grid connected), however, wind power is steadily growing with an estimated existing capacity of 56 GW by the end of 2005 (REN21 2005). Wind power has been used for many centuries to provide mechanical and electrical power for a variety of uses. Since the beginning of the last century, however, the most important use has been the generation of electricity for supply to rural and remote areas, as well as providing energy into the electrical distribution system, i.e. the national grid. World wind energy capacity has doubled every three years since 1990 and each doubling has been accompanied by a 15% reduction in the price of wind turbines (Milbrow 2005). Turbine size has increased from 600 - 800 kW to 1 - 3 MW with blade diameters from 60 -100 m and the energy costs (c/kWh) has declined by at least 18% and is now half those of 1990. The practical size of a wind turbine is determined by the assessment of annual electrical load, site conditions, wind resource, installed cost, and utility rate (Lodge 2005).The major countries that utilize wind power for electricity generation include the USA, Spain, Germany, India, Britain, Sweden, Netherlands, China, and Denmark. However, Russia, South Africa, Brazil, and Mexico are in the transitional stage to develop large-scale commercial markets. The basic theory of the extraction of energy from a wind turbine is found in any standard textbook on wind energy. The power in the wind varies as the cube of the wind speed. If an obstacle is placed in the path of the wind, the wind’s kinetic energy does work on the obstacle and wind energy is converted to other forms, including the kinetic energy of rotating parts. Thus a turbine or rotor placed in the path of wind, with wind speed,