Next Article in Journal
Sustainable Growth through Thai Native Chicken Farming: Lessons from Rural Communities
Previous Article in Journal
Artificial Neural Network and Adaptive Neuro Fuzzy Inference System Hybridized Models in the Sustainable Integration of Language and Mathematics Skills: The Case of Singapore and Hong Kong
Previous Article in Special Issue
Hybrid Photovoltaic Output Forecasting Model with Temporal Convolutional Network Using Maximal Information Coefficient and White Shark Optimizer
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Sustainability
Volume 16
Issue 17
10.3390/su16177810
sustainability-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles thumb_up
...
Endorse textsms
...
Comment
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Review

Offshore Wind Power: Progress of the Edge Tool, Which Can Promote Sustainable Energy Development

by
Xing Su
,
Xudong Wang
,
Wanli Xu
,
Liqian Yuan
,
Chunhua Xiong
and
Jinmao Chen
*
Systems Engineering Institute, AMS, PLA, Beijing 102300, China
*
Author to whom correspondence should be addressed.
Sustainability 2024, 16(17), 7810; https://doi.org/10.3390/su16177810
Submission received: 9 August 2024 / Revised: 28 August 2024 / Accepted: 3 September 2024 / Published: 7 September 2024
(This article belongs to the Special Issue Climate Change and Sustainability: Intelligent Operation and Maintenance of New Energy Systems)
Browse Figures
Versions Notes

Abstract

:
Offshore wind is renewable, clean, and widely distributed. Therefore, the utilization of offshore wind power can potentially satisfy the increasing energy demand and circumvent the dependence on fossil energy. Thus, offshore wind power is an edge tool for achieving sustainable energy development because of its potential in large-scale energy supply and its important role in reducing environmental pollution as well as carbon emission brought by fossil energy. The worldwide development of offshore wind power has entered the era of large-scale research and commercial application. It displays a trend of rapid development, continuous technological breakthroughs, and high-speed market growth. This article systematically introduces the structural components and technical characteristics of offshore wind power. Moreover, the current developmental status of offshore wind power is summarized. By reviewing the current development and application status of offshore wind power technology worldwide, large wind turbines and fixed and floating offshore wind power technologies are analyzed. Additionally, the development of the offshore wind energy market is overviewed. The policy condition and key aspects such as the construction, operation, and maintenance of offshore wind power plants are also summarized. Finally, the prospective challenges and development trends of offshore wind power and its significance in achieving sustainable society development are proposed. We consider that the article can provide reference and inspiration for researchers and developers dedicated to offshore wind power.

1. Introduction

With the substantial development of society, humans’ need for energy is increasing accordingly. This has promoted the excessive exploitation and use of conventional energy sources represented by fossil fuels. This, in turn, has resulted in the intensification of the problems of ecological environment pollution, international energy price fluctuations, and non-uniform resource distribution. The healthy development of nature and society is being hindered severely [1,2,3]. Offshore wind power generates green electricity from sea wind, which is a renewable energy source. It has become an essential method to address the energy crisis, solve the problems caused by fossil fuels, and satisfy the high-quality developmental needs of human society. This is because of the abundant wind resources, broad site selection space, low environmental influence, and proximity to coastal economic zones [4,5].
Offshore wind can be continuously regenerated and recovered in nature and is a new and renewable energy source that can be utilized. Theoretically, the global offshore wind energy reserves can effectively satisfy the energy needs for production and daily life [6,7]. Considering this, offshore wind power has been vigorously promoted and guided by government departments of various countries in the past decade. This has made it a hotspot with rapid development of technological research and applications. A large number of companies worldwide are competing to enter the field of offshore wind power. This is promoting the preparedness of the industrial chain. A large number of offshore wind plants have started operating (a simple schematic diagram of a wind plant is presented in Figure 1). This has formed a large-scale market that continues to grow rapidly [8,9].
The difference in wind energy utilization patterns and the bottom foundation results in diverse technological forms of offshore wind power. These have varied technical characteristics [10]. The different technological forms of offshore wind power have various ranges of application and industry chain completeness. Meanwhile, the components and developmental obstructions of engineering construction, daily operation, and maintenance also differ. These have become important factors in determining whether offshore wind power can be put into large-scale application [11]. This article briefly presents the structure and characteristics of offshore wind power. It focuses on the development of offshore wind turbines and offshore wind farm projects of numerous well-known research institutions and enterprises worldwide. By classifying the relevant technologies and indexes of offshore wind turbines, the technical characteristics and forms of large wind turbines and fixed and floating offshore wind power are summarized, the current status of industrial development is analyzed, and offshore wind power policies and the economics and market of offshore wind power are reviewed. The construction, operation, and maintenance processes of offshore wind power are described briefly. Finally, the challenge and future development direction for offshore wind power are forecasted, and the significance of offshore wind power for human sustainable development is clarified. We consider that this article will promote the development of offshore wind power.

2. Technical Characteristics of Offshore Wind Power

2.1. Overview of Offshore Wind Power Structure

Wind turbines are generally divided into two categories according to the upper turbine unit: horizontal-axis wind turbines and vertical axis wind turbines (Figure 2). The main axis of a horizontal-axis turbine is parallel to the horizontal plane, and the blades rotate around the horizontal-axis. The main axis of a vertical-axis turbine is perpendicular to the horizontal plane, and the blades rotate around the vertical axis. In addition to the difference in axis settings, the performance of the two types of turbines differs. Vertical axis wind turbines are suitable for situations where the wind direction is not steady, such as urban areas with high-rise and complex mountainous environments. Meanwhile, horizontal-axis wind turbines can be optimized by better adjusting the blade angle and shape characteristics to enhance efficiency. These are suitable for flat and open wind fields. Therefore, horizontal-axis wind turbines are generally selected as offshore wind turbines [12,13,14,15,16,17].
A vertical-axis wind turbine usually consists of blades, supporting wings, spindle components, a brake system, a generator, and a tower (Figure 3a). For a classical horizontal axis wind turbine, the structure mainly includes blades, a hub, a pitch system, a transmission system, a yaw system, a frequency conversion system, a generator, a tower, a wind measurement system, and a control system (Figure 3b). Furthermore, auxiliary structures for lubrication and braking are necessary [18,19]. For mature commercial offshore wind turbines, lightning protection, corrosion protection, salt spray protection, moisture-proofing, and functional dehumidification modules are also installed for better adaption to the offshore environment. This results in the extension of the service life of offshore wind turbines and a reduction in maintenance costs.
With the continuous progress of material technology, some piezoelectric materials are introduced into the field of wind power. The wind can cause the vibration of piezoelectric materials in the piezoelectric device and excite the materials to produce electricity. Thus, the conversion of mechanical energy to electricity is realized [20,21]. With the fast improvement of this technology, piezoelectric wind turbines are expected to be promoted and applied in special fields or even on a large scale of commercial use.

2.2. Analysis of Advantages and Disadvantages of Offshore Wind Power

Compared with wind power on land, offshore wind power has unique advantages [22]. First, offshore wind plants do not occupy land resources. This can alleviate the situation of land insufficiency caused by dense coastal populations. Second, compared with onshore wind power, wind power on the sea can utilize higher wind speed (usually about 20% higher than that on land) due to the flat and wide sea surface, can have higher utilization hours and stability, and can have a larger unit capacity (generally higher than 5 MW). Therefore, the extra annual generation capacity of offshore wind turbines sometimes can be 70% higher than that on land. This results in more efficient resource utilization. Third, offshore wind power is located near the coast and is generally close to the power load centers distributed along the coast. The generated electricity can be utilized nearby, thereby reducing transmission costs [23,24].
Offshore wind power also has certain disadvantages. For example, the technology is relatively complex, and the construction cost is high. The cost of an onshore wind power system is CNY 5100–6500/kW, while the construction cost of offshore wind power is about CNY 15,000–17,000/kW. The price of an offshore wind turbine is about CNY 6000–7000/kW, and the cost of a turbine accounts for about 40% of the total cost of wind power construction. Offshore wind power is more likely to be affected than onshore wind power during extreme weather such as typhoons. Therefore, a higher reliability performance of offshore wind power is required. This, in turn, necessitates higher requirements for the materials, structural design, and manufacturing processes [25]. From the perspective of operation and maintenance costs, offshore wind power operation and maintenance costs account for 25% to 30% of the cost per kWh, which is 1.5 to 2 times the cost of onshore wind power operation and maintenance.

3. Development Status of Offshore Wind Power Technology

After a continuous improvement for decades, offshore wind power has gradually developed toward large wind turbines. These can be classified into fixed wind power and floating wind power according to the form of bottom foundations.

3.1. Large Wind Turbine Technology

With the continuously expanding plans for projects and construction scale of offshore wind farms, the main wind turbine manufacturers have invested actively in the research and development of large offshore wind turbines. For example, offshore wind turbines in China have developed from 0.5 MW in 1990 to 16 MW in 2023. Moreover, 20 MW wind turbines are planned to be assembled (Figure 4) [26,27,28]. Large capacity, light weight, and intelligence are the important trends in the development of offshore wind turbine technology. These are in addition to the objective request for reducing the initial investment and operation costs. At present, there are plans to introduce offshore wind turbines with a rated capacity exceeding 14 MW to the market.
In terms of wind turbine types, with the continuous increase in generating capacity, turbines developed from the early application of constant speed and frequency squirrel cage asynchronous turbines to variable speed and constant-frequency, high-speed drive, doubly fed asynchronous turbines. Subsequently, direct drive permanent magnet synchronous turbines and semi-direct drive permanent magnet synchronous turbines without gearboxes have emerged [29,30]. Cage-type asynchronous wind turbines have a simple structure and are inexpensive. These are commonly used in small and medium-sized constant-speed and constant-frequency wind turbines in early wind farms. For example, Siemens’ early product (a 3.6 MW cage-type asynchronous wind turbine) was widely used in offshore wind plants in countries such as the United Kingdom and Germany. The doubly fed asynchronous turbines have the advantages of a wide speed range, independent adjustment of active and reactive power, and a small capacity of rotor excitation converter. For example, doubly fed asynchronous wind turbines with a single capacity of less than 4 MW manufactured by GE and Vestas were used in early offshore wind farms in the US and Europe [31,32].
Both cage-type asynchronous turbines and doubly fed asynchronous turbines have relatively small capacities. Most of these are below 6 MW. Therefore, synchronous motors appropriate for larger installed capacities are gradually capturing the market share of asynchronous motors. For synchronous motors, electrically excited direct drive units have a large number of rotor poles and a large volume. These have been applied to onshore wind farms but not to offshore wind farms. At present, offshore wind turbines are manufactured mainly through two technical routes: permanent magnet direct drive and permanent magnet semi-direct drive synchronous generator sets. From an economic perspective, the permanent magnet direct drive synchronous wind turbine system has the highest annual power generation, whereas the permanent magnet semi-direct drive synchronous wind turbine system has the lowest cost per kilowatt hour. Overall, the permanent magnet semi-direct drive synchronous wind turbine system displays good performance and economy. However, for large units above 10 MW, direct drive technology is preferred [33,34,35].
At present, the mainstream products of offshore wind turbines have attained capacities of 8–10 MW. Wind turbines of above 10 MW have been introduced since 2020 [36,37]. As shown in Table 1, Siemens Gamesa introduced the SG14-222DD offshore direct drive wind turbine in May 2020. It was the world’s largest single-unit capacity offshore wind turbine at that time. Its impeller diameter is 222 m, and its blade length is 108 m. The turbine has a low weight (500 tons) [38]. Compared with other heavier engine compartments, this lightweight design enables Siemens Gamesa to safely utilize optimized tower and foundation substructures. This reduces the cost of each unit by minimizing material procurement and transportation requirements.
General Electric launched the Haliade-X series of wind turbines at the end of 2020. These have a height of 260 m, an impeller diameter of 220 m, a blade length of 107 m, and a single unit capacity of up to 14 MW [39,40]. The combination of larger impeller diameter, longer blades, and higher capacity factor reduces the sensitivity of the Haliade-X 14 MW wind turbine to variations in wind speed. Meanwhile, the predictability is improved. It generates more electricity at low wind speeds.
In February 2021, Vestas announced the launch of the V236-15.0 MW offshore wind turbine. It has a single unit capacity of 15 MW, a wind turbine height of 260 m, an impeller diameter of 236 m, a blade length of 115.5 m, and an impeller sweep area of over 43,000 m2 (the world’s largest at that time). The annual power generation of a single unit is approximately 80 GWh. This is sufficient to satisfy the electricity demand of approximately 20,000 European households [40].
In August 2021, Mingyang Smart Energy released the MySE 16.0-242 offshore wind turbine. It has a rated power of 16 MW and an impeller diameter of 242 m. It can satisfy the development demand for fixed and floating offshore wind power. MySE 16.0-242 obtained design certifications from 16DNV and CGC certification [41].
In June 2023, the GWH252-16MW offshore wind turbine developed by Goldwind Technology was hoisted successfully at the Three Gorges offshore wind plant in Pingtan, Fujian. The unit has a single capacity of 16 MW, an impeller diameter of 252 m, and a single blade length of 123 m [42].
Overall, large offshore wind turbines have become a trend in the development of offshore wind power. On the one hand, large wind turbines can utilize wind power from a higher space, improve the power generation efficiency, and effectively reduce wind power generation costs. On the other hand, these have sufficient space to accommodate support equipment such as salt spray prevention, lightning protection, monitoring, and fire protection systems. This also reliably supports the development of offshore wind power toward deep–far sea areas.

3.2. Fixed Offshore Wind Power Technology

Fixed offshore wind power refers to the use of brackets to install wind turbines on the seabed. This is suitable for shallow and nearshore areas with a water depth of less than 50 m. Fixed offshore wind power is divided into the monopile type, jacket type, and tripod type (Figure 5) [43,44,45].
The monopile type is currently the most widely used type of offshore wind turbine. It is mainly composed of steel pipe piles fixed by inserting the pile legs below the seabed. It has the advantages of a simple structure and convenient construction. As shown in Table 2, Huaneng Cangnan No. 2 is built by China Railway Bridge Bureau. The monopile foundation structure of this project is the largest among wind power projects under construction in China. It has a diameter of 7.5–10.5 m, a length of up to 120 m, and a single weight of up to 2350 tons. The total installed capacity is 300 MW, and a total of 36 wind turbines of 8.5 MW are set up.
The jacket type generally has three to four pile legs. These are interconnected by struts to form a spatial truss structure with sufficient strength and stability. This type is suitable for water depths of 20–50 m. The Ormonde offshore wind farm is the first large-scale commercial wind farm in Europe to use a jacket base. The total installed capacity is 150 MW, with a single capacity of 5 MW and a total of 30 turbines. There are other typical cases, such as six Repower units in the Alpha Ventus (2010) offshore wind farm in Germany, two 5 MW turbines in the Beatrice (2006) demonstration offshore wind farm in the United Kingdom, and China’s first offshore wind power demonstration project in the Bohai Oilfield.
The tripod type is mainly composed of three pipe piles positioned uniformly on the seabed in the form of equilateral triangles. Steel sleeves are used to support the truss structure of the upper three legs. These form a relatively stable composite foundation. The advantage is that it has a low weight and good overall structural stability. In 2010, China’s Goldwind Intertidal 2.5 MW test unit Rudong Project was fully connected to the grid and put into operation, with an actual installed capacity of 32 MW.
In most cases, the equipment expenses including wind turbines, submarine cables, and other electrical appliances account for about 52% of the construction cost of wind power projects. Facilities and construction costs account for approximately 28%, while installation costs account for approximately 8%, and other expenses will take up approximately 12% of project costs. Fixed offshore wind turbines are mostly deployed in nearshore waters. Their construction costs are influenced by various factors such as water depth, offshore distance, marine environment, seabed geology, and typhoon susceptibility [47,48]. In addition, the wind resources and electricity prices in the area where the wind farm is located are important factors affecting the economic viability of the wind farm. The offshore distance and water depth have a certain influence on the average construction cost of offshore wind farms. However, the main factor is the water depth. When the offshore distance and water depth increase significantly, the construction expense of wind plants increases significantly because of more building structural materials, longer submarine cable for electricity delivery, higher standards on the offshore wind power installation ship, and longer time for transportation, operation, and maintenance. Due to differences in wind resources, turbine performance, electricity price, subsidy policies, and so on, the payback period of offshore wind power varies greatly, usually between 5 and 10 years, which needs investors’ patience.
Presently, wind farms are mainly constructed in fixed wind power routes. In the past decade, the cost of electricity generation for offshore wind has fallen from USD 0.197/kWh in 2012 to USD 0.081 in 2022. This is due to the improvement of offshore power technology and because larger and more efficient turbines that can capture more wind energy are put into wind farms. The large-scale expansion of wind power installations has also diluted the cost of wind farm infrastructure. In addition, the accumulation of experience in the construction, operation, and maintenance of offshore wind farms also means the reduction of unforeseen error costs.
In the future, with the popularization of large-capacity offshore wind turbines and the increasing maturity of offshore installation technology, the cost influence of the distance to shore and water depth for fixed offshore wind power will decrease gradually. The newly developed offshore wind power installation ship as well as the operation and maintenance ship provide convenience to the working team, cut down the project time, and enable the fixed offshore wind power deployed in deep–far seas. Furthermore, the introduction of the intelligent operation and maintenance system and advanced protection modules reduce the occupation of wind farm personnel and resources, saving later investment. Fixed offshore wind power fusion development technology will greatly increase the extra value of wind farms; one successful case is the combination of wind and fishery, in which seawater culture cages are fixed in the jacket-type fixed offshore wind power.

3.3. Floating Offshore Wind Power Technology

Floating offshore wind power is suitable for deep–far sea areas with a water depth of over 50 m. As shown in Figure 6, floating wind power is mainly divided into spar, semi-submersible, barge, and tension leg types according to the different forms of floating platforms. The upper turbine unit is supported by a floating foundation and is connected to the seabed through a mooring system. Floating offshore wind power is less affected by water depth and is not constrained by complex seabed topography and geological conditions. It has a broader applicable scope and can obtain more wind energy. This, in turn, provides broad prospects for development and utilization [49,50,51].
The spar type’s foundation has a smaller waterline surface. This can reduce the platform’s sway motion. As shown in Table 3, the Norwegian Hywind spar foundation technology was validated in the 30 MW Hywind Scotland project. It is currently applied to the Hywind Tampen offshore wind farm project in Norway. This project is the world’s largest offshore floating wind farm with an installed capacity of 88 MW (11 Siemens Gamesa 8.6 MW floating wind turbines). It was put into full operation in August 2023. Other spar-type offshore wind turbines such as Sway from Sway and Advanced Spar from Japan Marine United are also representative of floating offshore wind power [52,53,54,55].
Semi-submersible foundations have good motion performance, stability, and structural capability. WindFloat technology is the benchmark for semi-submersible floating wind turbines. It was applied in the first semi-submersible floating demonstration wind farm of WindFloat Atlantic (WFA). In January 2020, the first wind turbine of the 25 MW WindFloat Atlantic project in Portugal started to generate electricity after the cable was connected successfully to the wind farm and the substation in Viana Castle, Portugal. The floating wind farm is located 20 km from Viana Castle. It consists of three MHI Vestas V164-8.4 MW offshore wind turbines installed on Principle Power’s semi-submersible WindFloat foundation. Three WindFloat Atlantic foundations are anchored to the seabed with chains. Each has a height of 30 m and column spacing of 50 m [56,57].
In recent years, China has developed rapidly in the field of floating offshore wind power. A number of application projects have been demonstrated, mostly using semi-submersible technology routes.
As shown in Table 4, The “Yinling” of China Three Gorges Renewables is the first demonstration prototype of floating offshore wind power in China. It was officially connected to the grid and operated for power generation in December 2021. The wind turbine is a MySE5.5MW anti-typhoon floating offshore wind turbine. It was developed independently by Mingyang Smart Energy. The unit capacity attains 5.5 MW, the impeller diameter is 158 m, and the full power generation can attain 5500 kWh [58,59].
The “Fuyao” is floating wind power equipment designed, implemented, and tested by China State Shipbuilding Corporation (CSSC) according to deep-sea conditions. The height of its center hub is 96 m, the impeller diameter is 152 m, and the length of the blades is 74 m. The 6.2 MW wind turbines, voltage source mode converters, backup energy storage power sources, and smart microgrid control units form a self-sustaining smart microgrid. The system design provides better anti-typhoon safety for the “Fuyao” and obtains more sufficient motion load and motion attitude control data. This provides support for the grid-connected operation of the “Fuyao” ship [60,61].
The “Guanlan” is the first deep–far sea floating offshore wind power system in China. It is also the world’s first semi-submersible floating offshore wind power platform that operates in harsh marine environments and supplies power to offshore oil and gas farms. It is composed of a semi-submersible foundation and a wind turbine with an installed capacity of 7.25 MW. The China National Offshore Oil Corporation (CNOOC) invested in the project and constructed it. It is located in the offshore oil field area at a distance of approximately 136 km from Wenchang, Hainan. The floating wind turbine is moored in the design area with a water depth of 120 m by nine anchor chains. It is connected to the Wenchang 13-2 platform through a dynamic submarine cable. All of the electricity generated by the “Guanlan” is consumed by the oil field group through a 5 km dynamic submarine cable. The project was connected to the grid on 20 May 2023. Thereby, it became the world’s first “Double 100” offshore wind power project with a water depth of over 100 m and an offshore distance of over 100 km [62,63].
The “Guoneng Gongxiang” is the world’s first floating wind fishery-integrated project. It is supported by CHN Energy. The floating platform is a three-column semi-submersible structure with an equilateral triangle shape. The center-to-center distance between the columns is 70 m, the column height is 28 m, and the designed draft depth is 14 m. The platform is equipped with nine unsecured anchor chains 431 m long. Each column is connected to three mooring cables. This ensures the safe and stable production of the wind fishery combination platform even when offshore wind speeds attain 60 m/s (i.e., typhoons above level 17). This project integrates offshore wind power and offshore aquaculture. Thereby, it forms a new development model of “green energy + blue granary” [64].
The barge type’s foundation is a suitable platform type for shallow water. It has the advantages of small volume, low weight, shallow draft, and convenient construction and installation. However, this design results in the incapability of the platform to withstand violent wave force and respond strongly to roll and pitch movements in rough seas. This makes it suitable only for calm water areas. In 2018, the FLOATGEN project, jointly developed by Centrale Nantes and SEM-REV, was put into operation. Its floating foundation adopts the damping pool barge foundation developed by the French company Ideol (La Ciota, French). The typical barge foundations also include NREL/MIT wind turbines from the US and NMRI wind turbines from Japan [65].
A tension leg foundation has a small amplitude of out-of-plane movement and occupies a small sea area. However, its self-stability is ineffective. The floating wind turbine project of Provence Grand Large (PGL) Wind Farm in France adopts a tilted tension leg platform structure. The project entered the implementation stage in 2020. The platform was designed by SBM Offshore and IFP Energies Nouvelles. Its stable structure reduces tower movement. It does not require ballast pumps or other “active work” systems during operation. Its compact layout reduces the occupation of water areas. The non-catenary mooring also has a negligible impact on fisheries. This facilitates wet towage and mooring system installation. The project is located 40 km west of Marseille Port in France. It involves a water depth of approximately 100 m and an average wind speed of 10 m/s. It is anticipated that a total of three Siemens Gamesa SWT-8.0-154 wind turbines will be installed [66,67,68,69,70].
For floating wind power, more equipment is required to maintain balance and stability. Therefore, the installation and maintenance costs of floating offshore wind power are higher than those of fixed offshore wind power. At present, the main factor obstructing the development of floating wind power is the cost, including the investment cost, operation and maintenance cost, and equalization cost. With the continuous development of the floating offshore wind power industry, the expenses and risks of equipment, installation, operation, and dismantling of floating wind power will be reduced [71]. The technological innovation, optimization, scale expansion, standardization, and supply chain of floating wind power will become key factors in reducing the cost of the wind turbine unit, as well as its infrastructure, operation, and maintenance. According to a conservative prediction, the overall cost of floating offshore wind power will decrease by 38% by 2050. According to the International Energy Agency’s forecast, this cost reduction may attain 50%. At that time, floating wind power will become a new force in the field of offshore wind power [71,72,73].

4. Development Status of Offshore Wind Power Industry

4.1. Offshore Wind Power Policy

In recent years, both European nations in leading positions in offshore wind power (such as the UK, Germany, and the Netherlands) and rising stars such as China, the US, and France have made significant plans for increasing the scale of offshore wind power installations, proposed corresponding strategic development goals, intensely promoted the construction of wind farms and the development of industrial chains, and supported the development of floating wind power.
In September 2020, the Global Offshore Wind Alliance was jointly established by the International Renewable Energy Agency, the Danish government, and the Global Wind Energy Council. The aim is to “eliminate barriers to wind power generation”. Multiple countries, including the UK, Germany, the US, Japan, Belgium, Colombia, Ireland, Norway, and the Netherlands have joined. The organization proposes that to achieve the 1.5 °C target, the global cumulative installed capacity of offshore wind power needs to attain at least 2000 GW by 2050. In November 2020, the European Commission released the “EU Strategy for the Development of Offshore Renewable Energy”. The strategy proposes that the installed capacity of offshore wind power in the European Union will increase from the current 12 GW to at least 60 GW by 2030 and to 300 GW by 2050 [74].
In January 2022, the National Development and Reform Commission and the National Energy Administration of China released the “14th Five Year Plan for Modern Energy System”. It proposes to enhance the clean and low-carbon development level of energy in the eastern region, actively promote the development of offshore wind power clusters in the southeastern coastal areas, and focus on building offshore wind power bases in Guangdong, Fujian, Zhejiang, Jiangsu, Shandong, and other areas.
The proposal of these offshore wind power development policies not only comes from the pressure to achieve decarbonization goals but also from the practical considerations of promoting energy structure adjustment and increasing the proportion of renewable energy. Especially with the current energy situation in Europe, the demand for new energy development is even more urgent. In this situation, on the one hand, offshore wind power is an important component of renewable energy and has been developed and utilized on a large scale, making significant contributions to emission reduction. On the other hand, offshore wind power has a high degree of commercialization and rapid market growth, and also has the emerging field of floating wind power that urgently needs to be developed. The large-scale application, economic value, and market prospects make the development of offshore wind power sustainable, resulting in it becoming an important way for countries to achieve decarbonization goals.
Germany, as a model country for offshore wind power development, planned in the latest revised “Renewable Energy Law” (EEG2023) that the proportion of renewable energy electricity supply in Germany will increase from 65% to 80% by 2030. The plan to achieve carbon neutrality in electricity will be basically accomplished by 2035. The new plan significantly increases the capacity target, provides favorable policies, reduces financing costs, offers tax incentives, simplifies government procedures, and standardizes approval processes, which increases efforts to promote energy transition. Due to this policy support, thermal and nuclear power are gradually being phased out in Germany, and the proportion of renewable energy generation represented by offshore wind power is gradually increasing. Currently, it has reached more than 40% of the total power generation.
The EU’s incentive subsidy strategy for offshore wind power mainly includes Feed-in-Tariff (FIT), Feed-in-Premium (FIP), contract for difference (CFD), and bidding plan. FIT is launched when renewable technologies are immature and technological progress requires strong price signal support, providing strong investment incentives for the market. FIP is composed of premiums set by the administrative department, which are fixed over time and paid based on the market price of energy production, with long-term certainty. It provides partial protection against market price risks and increases incentives for the integration of the system and market.

4.2. Offshore Wind Power Market

According to statistics from the International Renewable Energy Agency (IRENA), the global offshore wind power installed capacity increased by 8.4 GW in 2022, with a cumulative installed capacity of 2062.6 GW. Of this, the offshore wind power installed capacity in China increased by 4.1 GW (accounting for 49%), with a cumulative installed capacity of 30.5 GW (accounting for 49%) [74,75,76,77] (Figure 7).
As an important economic factor affecting large-scale development, the overall cost of offshore wind power has decreased steadily. From the perspective of cost-per-kilowatt hour, the levelized cost of electricity (LCOE) for offshore wind power worldwide has decreased by 60% from 2010 to 2021: from USD 0.188/kWh to USD 0.075/kWh. In 2021, the LCOE of offshore wind farms in China was approximately equal to the grid parity electricity price of coal-fired power plants along the coast (CNY 0.40–0.50/kWh). In the future, with the trend of large-scale turbine development, the cost reduction of offshore projects would create a larger space for the cost reduction of wind power.
However, the difficulty of developing deep–far sea projects has increased. The requirements for infrastructure and transmission engineering, as well as the design cost of flexible DC transmission and floating foundations, will pose significant challenges to the development and construction of offshore wind power projects. The LCOE for floating offshore wind is still significantly higher than that for other types of renewable energy worldwide, estimated at USD 0.2/kWh. This is approximately four times the LCOE for fixed offshore wind and is significantly higher than that for onshore wind and solar power generation [78,79].
As a global leader in offshore wind power, Europe is in a leading position in technology research, commercial operations, market development, and industrial chain completeness. According to the most recent data from Wind Europe (a European wind power industry organization) the newly installed capacity in Europe will be 3.7 GW in 2022, with a cumulative installed capacity of 30.1 GW. Owing to the surge in electricity consumption and government policy support, the Asian offshore wind power market was positive in 2022. With a newly installed capacity of 4.7 GW and a cumulative installed capacity of 32.5 GW, it surpassed Europe to become the first offshore wind power market [80,81,82].
According to data from the National Energy Administration of China, in the first three quarters of 2023, the country’s offshore wind power installed capacity increased by 1.43 million kW. At the end of September 2023, the cumulative installed capacity of offshore wind power in China was 31.89 million kW. Offshore wind power has become a significant component of China’s wind power and even the entire renewable energy industry. It is an important force that needs to be considered in the adjustment and optimization of energy industrial structures [83].
In addition to the expansion of the overall scale, the construction scale of an offshore wind farm is also increasing. Numerous ultra-large wind farms with individual capacities of over 1 million kW have been put into operation or are under construction. Large-scale offshore wind farm projects can reduce the development cost of offshore wind power. The expansion of scale is conducive to reducing equipment procurement costs, as well as construction and operation expenses [84]. Owing to the substantial growth of deep-sea offshore wind power, the development space for large-scale offshore wind farms has been expanded. Moreover, the progress in research, engineering construction, and equipment level of ultra-large offshore wind turbines has provided technical feasibility. With more countries planning and constructing offshore wind power, global offshore wind power would develop toward a larger scale, a wider distribution, and the deeper sea.

4.3. Engineering Construction

At present, the installation and construction methods of offshore wind turbines are mainly divided into two types: In the split installation type, the sub-components (tower, hub, main engine, and blades) of the wind turbine are transported by ship to the wind turbine position and then assembled and installed by an installation ship (Figure 8a,b). In the integral installation type, the wind turbine components are assembled first at the rear base, transported or towed as a whole by a dedicated flatbed barge equipped with a seat frame, and then lifted and installed or anchored as a whole by a crane barge at the turbine position (Figure 8c,d) [85].
The offshore operation time of integral installation is short. The efficiency is high under certain environmental conditions. It is suitable for wind turbine integral installation in deep mud geological conditions. However, the cost is affected substantially by comprehensive resources. Moreover, integral installation is not suitable for conditions with deep water and large waves in the sea area. It has high requirements for the assembly base and transportation ships in the back yard. Split installation is more suitable for harsh sea conditions than integral installation, with lower requirements for ship equipment. The disadvantage of split installation is that it requires an excessive number of auxiliary ships, multiple processes, frequent high-altitude operations, and higher requirements for the geological conditions in the sea area. From the perspective of engineering construction, with high construction safety and efficiency, integral installation is suitable for large-scale wind farm construction. Split installation is suitable for wind farms at longer distances and has lower requirements for assembly base conditions. Currently, a large majority of offshore wind power installations use the split installation method [85,86].
The ships used for offshore wind turbine installation generally include offshore wind turbine installation ships and submarine cable-laying ships (Figure 9). Installation ships can be divided into four types based on their characteristics: crane ships, bottom-mounted installation ships, self-elevating wind power installation ships, and self-elevating and self-propelled installation ships [87]. The self-elevating wind power installation ship is currently the most common type of offshore wind power installation ship. This type of wind power installation ship can utilize the deep-sea operation characteristics of the drilling platform to conduct positioning operations in deeper sea areas. Self-elevating installation ships have the advantage of strong operational stability. However, these do not have self-propelled capabilities and can only be assisted by tugboats for installation. This increases the time consumed for machine position conversion at the construction site and reduces operational flexibility. The existing installation ships can essentially satisfy the installation requirements of wind turbines of below 9 MW. However, with the continuous development of the scale and increase in the distance from the coast for offshore wind power, as well as the complexity of sea conditions, the lifting capacity and lifting height of the installation ships are increasing continuously. In this situation, self-elevating and self-propelled installation ships designed and constructed specifically for wind turbine installation have emerged. These have the functions of transportation, self-propulsion, self-elevation, lifting, power positioning, etc. These are currently the most advanced type of wind power installation ship and have become the most preferred equipment for offshore wind power construction worldwide. They combine the advantages of a self-elevating platform and a floating ship and are specifically designed and constructed for offshore wind turbine installation. Typical self-elevating and self-propelled installation ships include the offshore wind power installation ship “Orion” of the Belgian DEME Group, the world’s first fourth-generation self-elevating wind power installation ship N966 “Voltaire” constructed by Qidong Zhongyuan Shipping Offshore Engineering, the wind power crane installation ship “Ulstein HX122” with a lifting capacity of 8000 tons launched by Ulstein, and the 2000-ton offshore wind power installation platform “Baihetan” constructed by China [88,89].
After installing the wind turbine, it is necessary to lay the cables through a submarine cable-laying ship to connect the offshore booster station and the power grid on land.

4.4. Operation and Maintenance of Offshore Wind Power

The operation and maintenance capability is an important component of the offshore wind power industry chain. It is also an important aspect for ensuring the development of the offshore wind power industry, particularly that of offshore wind power in the deep–far sea. At present, the international operation and maintenance mode mainly adopts a combination of monitoring systems and maintenance ships. The monitoring center is in charge of monitoring the operation of various pieces of equipment in the project and conducting status detection, fault diagnosis, and fault prediction. Operation and maintenance ships are specialized vessels used for operating and maintaining offshore wind turbines. Various forms of operation and maintenance ships exist. These are generally divided into ordinary operation and maintenance ships, professional operation and maintenance ships, operation and maintenance mother ships, and self-elevating operation and maintenance ships. Professional operation and maintenance ships constitute the most important accessibility equipment. These are widely used in various offshore wind plants. Operation and maintenance mother ship refers to a larger vessel used for offshore wind power operation and maintenance, which provides accommodation for personnel and stores spare parts. A self-elevating maintenance ship refers to a vessel mainly used for replacing large components (gearboxes, generators, etc.) in offshore wind power maintenance. It has a certain lifting capacity and self-elevating platform and can adapt to most sea areas within a depth of 40 m [90,91].
The operation and maintenance mode of offshore wind power displays a trend toward digitization and accuracy. The objective for this type of offshore wind power development trend is to promote the reduction of operation and maintenance costs and the improvement of the electricity generation efficiency throughout the project’s life cycle. Ultimately, it will improve the operational efficiency of offshore wind farms [92,93].

5. Discussion

5.1. Challenges in the Development of Offshore Wind Power

As an important component of renewable energy, although offshore wind power is currently in a growing stage of development, it encounters certain challenges and problems:
  • The stability of offshore wind power output is insufficient. The wind direction and speed at sea are generally affected by seasonality and weather. Periods of low or zero wind generally occur every year. In certain areas, typhoon weather may occur. Both low and high wind speeds can influence the electricity generation of offshore wind power, thereby resulting in fluctuations in power output. To reduce the constraints on the use of electricity, it is necessary to smooth out the fluctuations in offshore wind power, expand the range of offshore wind power operation conditions, and improve wind power generation efficiency.
  • The development of offshore wind power is subject to restrictions on maritime rights. With the intensive development of offshore wind power in the early stages, large-scale wind farms have been opened up along the coast. However, the use of marine resources needs to be considered comprehensively. If the establishment of wind farms is not restricted, it would cause a shortage of coastal sea resources by affecting the passage of waterways and the development of other industries such as fisheries, mining, and tourism. Therefore, certain regions in China have temporarily slowed down the establishment of offshore wind farms. The allocation and use of offshore wind power rights need to be determined scientifically and reasonably.
  • The construction cost of offshore wind power is relatively high. The construction of offshore wind power requires the consideration of the investment cost of offshore engineering operations. A rational design of wind turbines should consider the special offshore environment, such as the high temperature, high humidity, high salt spray, high ultraviolet radiation, typhoons, and erosion caused by marine organisms. Therefore, the expenses for multiple protection modules need to be considered. The simultaneous construction of submarine cables and offshore booster stations results in higher initial construction costs than those for onshore wind power. The reduction of the cost of offshore wind power is a major challenge for its future development.
  • Offshore wind power operation and maintenance needs large resource investments. Unlike onshore wind power, offshore wind power is at a distance from the coast and requires the transportation of personnel, equipment, and accessories by ship. Therefore, professional engineering ships and maintenance ships are the key to offshore wind power operation and maintenance. This results in the complexity of offshore wind power operation and maintenance involves more personnel and equipment investment and occupies and consumes more resources than those for onshore wind power.
  • The offshore wind power market mechanism needs further improvement. There are indications of weakening financial support from the government for offshore wind power: China proposed in 2020 that newly established offshore wind power farms will no longer enjoy the central government subsidies. In addition, the current maritime management laws and related supporting systems are applicable only to a single industry, the approval of offshore wind power is relatively complex, and a comprehensive offshore development system is absent. The system that can scientifically and reasonably promote the steady development of offshore wind power needs to be supplemented and improved urgently.

5.2. Developmental Trend of Offshore Wind Power

With the continuous improvement of offshore wind power technology and large-scale installation in various countries around the world, the development of offshore wind power presents a new trend (Figure 10). It is also an attempt to address the development issues and challenges of offshore wind power.
  • The capacity of offshore wind turbines is increasing. Large wind turbines can fully utilize offshore wind resources, improve power generation efficiency, reduce the impact of wind fluctuations, effectively offset the cost increase caused by offshore construction operations, and reduce power generation costs.
  • The locations of offshore wind plants are developing from near sea to deep–far sea. The wind energy resources in the deep–far sea areas with offshore distances larger than 100 km and water depths exceeding 50 m have increased in number after the saturation of wind farm resources near the coast. Offshore wind power will be large-scale, clustered, and located in deep–far seas in the future.
  • Intelligent operation and maintenance. With the increasing maturity of digital twin technology, long-term maintenance-free technology, and intelligent monitoring technology for wind turbines, the frequency of maintenance and staffing efforts in offshore wind plants will decrease gradually. Thus, resource investment would be reduced when power generation is ensured.
  • Overall cost reduction. With the gradual maturity of technology and industrial chains, as well as the large-scale development of the industry, the construction and operation costs of offshore wind turbines are displaying a downward trend. The production and manufacturing costs of offshore wind turbine equipment are decreasing gradually. Offshore operation and maintenance are gradually being undertaken by specialized companies. The large-scale operation and maintenance of wind power would also dilute the costs. Moreover, offshore wind power is convenient for consumption in coastal economic zones, thereby reducing power losses and transmission costs.
  • Integrated development and comprehensive utilization of marine resources. Offshore wind power has been introduced gradually in conjunction with fishing, oil and gas, hydrogen production, and desalination. This shows a trend of integrated development with other resources on the same sea area or platform.
  • Continuous improvement of development policies. Although the central subsidies in certain countries are decreasing gradually, local subsidy mechanisms are constantly being introduced and improved in certain provinces and cities. The integration technology of offshore wind power with other industries also provides a technical foundation for the detailed planning for the ocean and the establishment of a compatible development and utilization mechanism for the sea area. In the future, through the refined and characteristic development as well as management of marine resources, the maximum value of marine areas will be utilized. This will enable multiple industries to develop synergistically in the same marine area.

5.3. Offshore Wind Power and Sustainable Development

As a new and renewable energy source, offshore wind power has high significance for the ecological environment and sustainable development.
  • Reduce environmental pollution and carbon emissions. Offshore wind power energy originates from sea wind and has good-scale economic effects. This can induce the upgrading of the energy industry, eliminate outdated high-emission energy industries, reduce the use of fossil fuels such as coal and oil, decrease the emission of greenhouse gases such as carbon dioxide, and cause a reduction in air pollutants such as sulfur and nitrogen oxide. This would reduce environmental pollution and mitigate the impact of climate change.
  • Reduce the pressure on land utilization. The construction of offshore wind plants does not reduce the available land area; has a minimal impact on agriculture, forestry, and wildlife habitats; and prevents competition with residential or industrial land. This is particularly important in populated areas with limited or expensive land resources. Thereby, it would provide a broader space for the scientific development and layout of local economies.
  • Contribute to sustainable energy development. As a rapidly expanding renewable energy source, offshore wind power plays an important role in sustainable energy development. By developing offshore wind power, the proportion of traditional environment-unfriendly fossil energy would be reduced gradually, and the upgrade as well as transformation of the energy industrial structure can be achieved. A scientific and rational layout of long-term construction of wind power can contribute to sustainable energy development through a stepwise establishment project of offshore wind power, from onshore, nearshore, and, finally, to deep–far sea, meeting today’s energy needs without compromising the ability of future generations to meet their needs.
  • Promote the comprehensive development of industries. The development of offshore wind power involves the industry chain of wind turbines and industries such as shipbuilding, power grid, information network, energy storage, and green power trading. In addition, offshore wind power can also be integrated with offshore industries such as fisheries, mining, and tourism to utilize marine resources in a cascade manner. Therefore, the development of the offshore wind power industry has a driving effect and can effectively promote the comprehensive development of the regional economy and industry; for example, the Ocean Ranch and the Three Gorges 300 MW offshore wind power integration demonstration project in Changyi City, in which the total installed capacity is 300 MW. It can provide about 940 million kWh of clean electricity per year, which can meet the annual electricity need of about 400,000 households. It has significant economic benefits and energy saving and emission reduction benefits that can save about 290,000 tons of standard coal and reduce about 790,000 tons of carbon dioxide every year. In addition, the construction of the Ocean Ranch relied on the built wind turbine foundation, and the integrated system simultaneously provided electricity and met people’s demand for seafood products, which has had a positive impact on sustainable development.
The gradual popularization and application of offshore wind power globally in the future would promote the optimization and transformation of the global energy structure, reduce the dependence on fossil fuels, alleviate the impact on the environment, and recover the global ecological environment. This would strongly support the achievement of the goals of global sustainable development and a community with a shared future for humanity.

6. Conclusions

Offshore wind power is a clean energy resource that generates electricity through renewable sea wind. It can solve the electricity problem in coastal economic zones and alleviate the side effects of using fossil fuels on the ecological environment. Therefore, it is a potential direction for energy development and sustainable development, with a substantial industrial development space.
With the extensive research and long-term commercial application of offshore wind power, the technology has matured gradually, and different forms of technology have been developed. It can adapt to different offshore environments and satisfy the power generation requirements of offshore wind farms. With the guidance of offshore wind power policies and the gradual development and improvement of the entire industry chain, the offshore wind power market has flourished.
This article summarizes the characteristics of offshore wind power, briefly describes the structure of offshore wind power, analyzes the advantages and disadvantages of offshore wind power, summarizes its technological and industrial development status, and lists and analyzes large turbine technology and fixed offshore and floating offshore wind power generation technology. Subsequently, the market development of offshore wind power is summarized, including the policies, market and economy, engineering installation, and operation and maintenance. The problems and challenges encountered in the development of offshore wind power are discussed. The future developmental trend of offshore wind power toward being large-scale, deep-sea, integrated, and intelligent, as well as other directions under policy support guidance, is proposed. Finally, the significance of offshore wind power for sustainable development is summarized. We consider that this article can provide reference and inspiration for researchers and institutions in offshore wind power. Thereby, it would promote the healthy development of offshore wind power and contribute to global sustainable development.

Author Contributions

Conceptualization, X.S. and X.W.; validation, J.C., C.X. and W.X.; formal analysis, L.Y.; investigation, X.S.; resources, J.C.; data curation, W.X.; writing—original draft preparation, X.S.; writing—review and editing, J.C.; visualization, L.Y.; supervision, J.C.; project administration, C.X.; funding acquisition, X.W. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Data Availability Statement

Not applicable.

Acknowledgments

We thank the reviewers for their reviewing and effective recommendations, and thank the editors for their professional guidance.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Zou, C.; Zhao, Q.; Zhang, G.; Xiong, B. Energy revolution: From a fossil energy era to a new energy era. Nat. Gas Ind. B 2016, 3, 1–11. [Google Scholar] [CrossRef]
  2. López-Castrillón, W.; Sepúlveda, H.H.; Mattar, C. Off-Grid Hybrid Electrical Generation Systems in Remote Communities: Trends and Characteristics in Sustainability Solutions. Sustainability 2021, 13, 5856. [Google Scholar] [CrossRef]
  3. Holechek, J.L.; Geli, H.M.E.; Sawalhah, M.N.; Valdez, R. A Global Assessment: Can Renewable Energy Replace Fossil Fuels by 2050? Sustainability 2022, 14, 4792. [Google Scholar] [CrossRef]
  4. Leung, D.Y.C.; Yang, Y. Wind energy development and its environmental impact: A review. Renew. Sustain. Energy Rev. 2012, 16, 1031–1039. [Google Scholar] [CrossRef]
  5. Song, D.; Fan, T.; Li, Q.; Joo, Y.H. Advances in Offshore Wind. J. Mar. Sci. Eng. 2024, 12, 359. [Google Scholar] [CrossRef]
  6. Gaudiosi, G. Offshore wind energy prospects. Renew. Energy 1999, 16, 828–834. [Google Scholar] [CrossRef]
  7. Li, G.; Wang, J.; Liu, F.; Wang, T.; Zhou, Y.; Tian, A. Regional Differences and Convergence of Technical Efficiency in China’s Marine Economy under Carbon Emission Constraints. Sustainability 2023, 15, 7632. [Google Scholar] [CrossRef]
  8. Council, Global Wind Energy. Global Offshore Wind Report 2020; GWEC: Brussels, Belgium, 2020; Volume 19, pp. 10–12. [Google Scholar]
  9. Guo, X.; Chen, X.; Chen, X.; Sherman, P.; Wen, J.; McElroy, M. Grid integration feasibility and investment planning of offshore wind power under carbon-neutral transition in China. Nat. Commun. 2023, 14, 2447. [Google Scholar] [CrossRef]
  10. Esteban, M.D.; Diez, J.J.; López, J.S.; Negro, V. Why offshore wind energy? Renew. Energy 2011, 36, 444–450. [Google Scholar] [CrossRef]
  11. Zhou, P.; Yin, P.T. An opportunistic condition-based maintenance strategy for offshore wind farm based on predictive analytics. Renew. Sustain. Energy Rev. 2019, 109, 1–9. [Google Scholar] [CrossRef]
  12. Sun, C.; Chen, J.; Tang, Z. New energy wind power development status and future trends. In Proceedings of the International Conference on Advanced Electrical Equipment and Reliable Operation (AEERO), Beijing, China, 15–17 October 2021; IEEE: Piscataway, NJ, USA, 2021; pp. 1–5. [Google Scholar]
  13. Al-Rawajfeh, M.A.; Gomaa, M.R. Comparison between horizontal and vertical axis wind turbine. Int. J. Appl. 2023, 12, 13–23. [Google Scholar] [CrossRef]
  14. Roy, S.; Das, B.; Biswas, A. A comprehensive review of the application of bio-inspired tubercles on the horizontal axis wind turbine blade. Int. J. Environ. Sci. Technol. 2023, 20, 4695–4722. [Google Scholar] [CrossRef]
  15. Nassar, W.M.; Anaya-Lara, O.; Ahmed, K.H.; Campos-Gaona, D.; Elgenedy, M. Assessment of Multi-Use Offshore Platforms: Structure Classification and Design Challenges. Sustainability 2020, 12, 1860. [Google Scholar] [CrossRef]
  16. Jiang, Z. Installation of offshore wind turbines: A technical review. Renew. Sustain. Energy Rev. 2021, 139, 110576. [Google Scholar] [CrossRef]
  17. Pan, L.; Zhu, Z.; Shi, Z.; Wang, L. Modeling and Investigation of Blade Trailing Edge of Vertical Axis Offshore Wind Turbine. Sustainability 2021, 13, 10905. [Google Scholar] [CrossRef]
  18. Koh, J.H.; Ng, E.Y.K. Downwind offshore wind turbines: Opportunities, trends and technical challenges. Renew. Sustain. Energy Rev. 2016, 54, 797–808. [Google Scholar] [CrossRef]
  19. Peng, H.; Li, S.; Shangguan, L.; Fan, Y.; Zhang, H. Analysis of Wind Turbine Equipment Failure and Intelligent Operation and Maintenance Research. Sustainability 2023, 15, 8333. [Google Scholar] [CrossRef]
  20. Ali, A.; Ali, S.; Shaukat, H.; Khalid, E.; Behram, L.; Rani, H.; Altabey, W.A.; Kouritem, S.A.; Noori, M. Advancements in piezoelectric wind energy harvesting: A review. Results Eng. 2024, 21, 101777. [Google Scholar] [CrossRef]
  21. Wu, H.; Ke, S.; Lu, M.; Gao, M.; Tian, W.; Liu, D.; Li, Y.; Wang, T. Research on vibration suppression effect and energy dissipation mechanism of wind turbine piezoelectric blade. J. Fluid. Struct. 2023, 117, 103814. [Google Scholar] [CrossRef]
  22. Zhu, L.; Zheng, H.; Ji, H.; Li, G.; Li, H.; Yao, S. Development trends and suggestions on offshore wind power of China. In Proceedings of the IEEE Sustainable Power and Energy Conference (iSPEC), Nanjing, China, 23–25 December 2021; IEEE: Piscataway, NJ, USA, 2021; pp. 2043–2048. [Google Scholar]
  23. Zhu, H.; Du, Z.; Wu, J.; Sun, Z. Innovation environment and opportunities of offshore wind turbine foundations: Insights from a new patent analysis approach. World Pat. Inf. 2022, 68, 102092. [Google Scholar] [CrossRef]
  24. Tian, Y.; Kou, L.; Han, Y.; Yang, X.; Hou, T.; Zhang, W. Evaluation of offshore wind power in the China sea. J. Energy Explor. Exploit. 2021, 39, 1803–1816. [Google Scholar] [CrossRef]
  25. Bhattacharya, S.; Kammen, D. Greener is Cheaper: An Example Form Offshore Wind Farms. Natl. Inst. Econ. Rev. 2024, 1–17. [Google Scholar] [CrossRef]
  26. Pryor, S.C.; Barthelmie, R.J. Wind shadows impact planning of large offshore wind farms. Appl. Energy 2024, 359, 122755. [Google Scholar] [CrossRef]
  27. Wang, J.; Wei, X.; Juanatas, R. Study on the optimization strategy of offshore wind power. Int. J. Low-Carbon Technol. 2023, 18, 367–372. [Google Scholar] [CrossRef]
  28. Huang, J.; Huang, X.; Song, N.; Ma, Y.; Wei, D. Evaluation of the Spatial Suitability of Offshore Wind Farm—A Case Study of the Sea Area of Liaoning Province. Sustainability 2022, 14, 449. [Google Scholar] [CrossRef]
  29. Huang, R.; Li, H.; Fei, F.; Qi, Y.; Song, T.; Zheng, S. Research on a New Control Method of Squirrel Cage Induction Generator for Wind Turbine. In Proceedings of the 2023 3rd International Conference on New Energy and Power Engineering (ICNEPE), Huzhou, China, 24–26 November 2023; IEEE: Piscataway, NJ, USA, 2023; pp. 445–449. [Google Scholar]
  30. Kadam, D.P.; Kushare, B.E. Overview of different wind generator systems and their comparisons. Int. J. Eng. Sci. 2012, 2, 1076–1081. [Google Scholar]
  31. Zhang, X.; Gao, H.; Cao, B. Research on fault causes and treatment methods of squirrel-cage asynchronous wind turbine. J. Phys. Conf. Ser. 2023, 2488, 012026. [Google Scholar] [CrossRef]
  32. Zhuo, Z.Y.; Chen, M.J.; Li, X.Y. A comparative analysis of carbon reduction potential for directly driven permanent magnet and doubly fed asynchronous wind turbines. Energy Sci. Eng. 2023, 11, 978–988. [Google Scholar] [CrossRef]
  33. Moudden, A.; Hmidat, A.; Aarib, A. Comparison of the active and reactive powers of the asynchronous cage machine and the doubly fed induction generator used in wind turbine energy in the case of decentralized production on an isolated site. Int. J. Electr. Eng. Inform. 2023, 15, 50–63. [Google Scholar] [CrossRef]
  34. Alexandrova, Y.; Semken, R.S.; Pyrhönen, J. Permanent magnet synchronous generator design solution for large direct-drive wind turbines. Int. Rev. Electr. Eng. (IREE) 2013, 8, 6. [Google Scholar]
  35. Zhang, R.; Gao, L. Research on the design and optimization of 1.5 MW semi-direct drive permanent magnet synchronous wind turbine. Energy Rep. 2022, 8, 589–598. [Google Scholar] [CrossRef]
  36. Jin, Y.; Zeng, Z.; Chen, Y.; Xu, R.; Ziegler, A.D.; Chen, W.; Ye, B.; Zhang, D. Geographically constrained resource potential of integrating floating photovoltaics in global existing offshore wind farms. Adv. Appl. Energy 2024, 13, 100163. [Google Scholar] [CrossRef]
  37. International Renewable Energy Agency (IRENA). Floating Offshore Wind Outlook 2024; International Renewable Energy Agency: Abu Dhabi, United Arab Emirates, 2024. [Google Scholar]
  38. Ding, H.; Zou, G.; Wang, F.; Xu, C. Modelling and control strategies of DC offshore wind farm. In Proceedings of the 2023 8th Asia Conference on Power and Electrical Engineering (ACPEE), Tianjin, China, 14–16 April 2023; IEEE: Piscataway, NJ, USA, 2023; pp. 1224–1228. [Google Scholar]
  39. Ryu, G.H.; Kim, D.; Kim, D.Y.; Kim, Y.G.; Kwak, S.J.; Choi, M.S.; Jeon, W.; Kim, B.S.; Moon, C.J. Analysis of vertical wind shear effects on offshore wind energy prediction accuracy applying rotor equivalent wind speed and the relationship with atmospheric stability. Appl. Sci. 2022, 12, 6949. [Google Scholar] [CrossRef]
  40. O’Neill, S. Giant turbines poised to claim offshore wind. Engineering 2021, 7, 894–896. [Google Scholar] [CrossRef]
  41. Li, J.; Shi, W.; Zhang, L.; Michailides, C.; Li, X. Wind–wave coupling effect on the dynamic response of a combined wind–wave energy converter. J. Mar. Sci. Eng. 2021, 9, 1101. [Google Scholar] [CrossRef]
  42. Alnmr, A.; Mayassah, M. Innovations in Offshore Wind: Reviewing Current Status and Future Prospects with a Parametric Analysis of Helical Pile Performance for Anchoring Mooring Lines. J. Mar. Sci. Eng. 2024, 12, 1040. [Google Scholar] [CrossRef]
  43. O’Kelly, B.C.; Arshad, M. Offshore Wind Turbine Foundations–Analysis and Design Offshore Wind Farms; Woodhead Publishing: Cambridge, UK, 2016; pp. 589–610. [Google Scholar]
  44. Díaz, H.; Soares, C.G. Review of the current status, technology and future trends of offshore wind farms. Ocean. Eng. 2020, 209, 107381. [Google Scholar] [CrossRef]
  45. Chen, J.; Kim, M.-H. Review of Recent Offshore Wind Turbine Research and Optimization Methodologies in Their Design. J. Mar. Sci. Eng. 2022, 10, 28. [Google Scholar] [CrossRef]
  46. Cui, L. Current Status of Marine Energy Technology and Industry; National Ocean Technology Center: Tianjin, China, 2024. [Google Scholar]
  47. Yeter, B.; Garbatov, Y. Structural integrity assessment of fixed support structures for offshore wind turbines: A review. Ocean. Eng. 2022, 244, 110271. [Google Scholar] [CrossRef]
  48. Maienza, C.; Avossa, A.M.; Ricciardelli, F.; Scherillo, F.; Georgakis, C.T. A comparative analysis of construction costs of onshore and shallow-and deep-water offshore wind farms. In Proceedings of the XV Conference of the Italian Association for Wind Engineering: IN-VENTO 2018, Naples, Italy, 9–12 September 2018; Springer International Publishing: Berlin, Germany, 2019; pp. 440–453. [Google Scholar]
  49. Wang, Z.; Carriveau, R.; Ting, D.S.K.; Xiong, W.; Wang, Z. A review of marine renewable energy storage. Int. J. Energy Res. 2019, 43, 6108–6150. [Google Scholar] [CrossRef]
  50. Yuan, J.; Cheng, Z.; Liu, D. Design of Variable Pitch Control Method for Floating Wind Turbine. Energies 2023, 16, 821. [Google Scholar] [CrossRef]
  51. Hong, S.; McMorland, J.; Zhang, H.; Collu, M.; Halse, K.H. Floating offshore wind farm installation, challenges and opportunities: A comprehensive survey. Ocean. Eng. 2024, 304, 117793. [Google Scholar] [CrossRef]
  52. Sun, X.; Huang, D.; Wu, G. The current state of offshore wind energy technology development. Energy 2012, 41, 298–312. [Google Scholar] [CrossRef]
  53. Zhanga, L.; Jiang, Y.; Li, Y. Preliminary study on the interaction of two floating offshore wind turbines. In Proceedings of the International Ocean and Polar Engineering Conference–ISOPE 2020, Shanghai, China, 11–16 October 2020. ISOPE-I-20-1172. [Google Scholar]
  54. Day, A.H.; Babarit, A.; Fontaine, A.; He, Y.P.; Kraskowski, M.; Murai, M.; Penesis, I.; Salvatore, F.; Shin, H.K. Hydrodynamic modelling of marine renewable energy devices: A state of the art review. Ocean. Eng. 2015, 108, 46–69. [Google Scholar] [CrossRef]
  55. Yoshimoto, H.; Awashima, Y.; Kitakoji, Y.; Suzuki, H. Development of floating offshore substation and wind turbine for Fukushima FORWARD. In Proceedings of the International Symposium on Marine and Offshore Renewable Energy, Tokyo, Japan, 28–30 October 2013. [Google Scholar]
  56. Roddier, D.; Cermelli, C.; Aubault, A.; Weinstein, A. WindFloat: A floating foundation for offshore wind turbines. J. Renew. Sustain. Energy 2010, 2, 033104. [Google Scholar] [CrossRef]
  57. Edwards, E.C.; Holcombe, A.; Brown, S.; Ransley, E.; Hann, M.; Greaves, D. Evolution of floating offshore wind platforms: A review of at-sea devices. Renew. Sustain. Energy Rev. 2023, 183, 113416. [Google Scholar] [CrossRef]
  58. Luo, D.H.; He, L. The world’s first typhoon-resistant floating offshore wind turbine has been built. Science and Technology Daily, 28 July 2021. [Google Scholar]
  59. Li, X.Y.; Fan, K.; Yang, X. “Three Gorges Leading”: China’s floating offshore wind power technology leader. Manag. Res. Sci. Technol. Achiev. 2023, 18, 2. [Google Scholar]
  60. Ma, Y.; Huang, Q.P.; Dong, Y.H. China’s Independent Research and Development of Far-Reaching Sea Floating Offshore Wind Power Equipment Operation Generation—“Fuyao” Offshore “Wind”. Website of Maritime Bureau of Guangxi Zhuang Autonomous Region. 2023. Available online: https://mp.weixin.qq.com/s?__biz=MjM5MTExODIxNg==&mid=2652649268&idx=2&sn=60e1418dbcd46506112241f88c7d859f&chksm=bd52f1d38a2578c5bec2c115c16be64d9f4225be67701a47193b2cf985fbf1e5253739da9219&scene=27 (accessed on 8 August 2024).
  61. Zeng, X.; Shao, Y.; Feng, X.; Xu, K.; Jin, R.; Li, H. Nonlinear hydrodynamics of floating offshore wind turbines: A review. Renew. Sustain. Energy Rev. 2024, 191, 114092. [Google Scholar] [CrossRef]
  62. Yan, X.R.; Zhang, N.N.; Ma, K.C.; Wei, C.; Yang, S.; Pan, B.B. Overview of Current Situation and Trend of Offshore Wind Power Development in China. Power Gener. Technol. 2024, 45, 1–12. [Google Scholar]
  63. Lu, X.R. “Guanlan” skill, green electricity across the far-reaching sea. China Pet. Petrochem. Corp. 2023, 8, 42–45. [Google Scholar]
  64. Lu, C.K. “National energy sharing number” opens the integrated development mode of fish and electricity. Science and Technology Daily, 24 October 2023. [Google Scholar]
  65. Choisnet, T.; Rogier, E.; Percher, Y.; Courbois, A.; Le Crom, I.; Mariani, R. Performance and mooring qualification in Floatgen: The first French offshore wind turbine project. 16ième Journées l’Hydrodynamique 2018, 1, 1–10. [Google Scholar]
  66. Gomes, J.G.; Lin, Y.; Jiang, J.; Yan, N.; Dai, S.; Yang, T. Review of offshore wind projects status: New approach of floating turbines. In Proceedings of the International Conference on Power and Energy Applications (ICPEA), Guangzhou, China, 18–20 November 2022; IEEE: Piscataway, NJ, USA, 2022; pp. 676–686. [Google Scholar]
  67. González, S.F.; Diaz-Casas, V. Present and Future of Floating Offshore Wind. In Floating Offshore Wind Farms; Springer: Berlin/Heidelberg, Germany, 2016; pp. 1–22. [Google Scholar]
  68. Henderson, A.R.; Witcher, D. Floating offshore wind energy—A review of the current status and an assessment of the prospects. Wind Eng. 2010, 34, 1–16. [Google Scholar] [CrossRef]
  69. Crowle, A.; Thies, P.R. Port and Installation Constraints of Tension Leg Platforms (TLP) Floating Wind Turbines. 2022. Available online: http://hdl.handle.net/10871/131320 (accessed on 8 August 2024).
  70. Pantusa, D.; Tomasicchio, G.R. Large-scale offshore wind production in the Mediterranean Sea. Cogent Eng. 2019, 6, 1661112. [Google Scholar] [CrossRef]
  71. Li, J.; Wang, G.; Li, Z.; Yang, S.; Chong, W.T.; Xiang, X. A review on development of offshore wind energy conversion system. Int. J. Energy Res. 2020, 44, 9283–9297. [Google Scholar] [CrossRef]
  72. Zhou, B.; Zhang, Z.; Li, G.; Yang, D.; Santos, M. Review of key technologies for offshore floating wind power generation. Energies 2023, 16, 710. [Google Scholar] [CrossRef]
  73. International Energy Agency (IEA). Net Zero Emissions by 2050; International Energy Agency: Paris, France, 2021. [Google Scholar]
  74. Swamy, S.K.; Gonzalez-Aparicio, I.; Chrysochoidis-Antsos, N. Developing a long-lasting offshore wind business case towards a Dutch decarbonised energy system by 2050. J. Phys. Conf. Series 2022, 2151, 012010. [Google Scholar] [CrossRef]
  75. Chen, Y.; Lin, H. Overview of the development of offshore wind power generation in China. Sustain. Energy Technol. 2022, 53, 102766. [Google Scholar] [CrossRef]
  76. Musial, W.; Spitsen, P.; Duffy, P.; Beiter, P.; Shields, M.; Mulas Hernando, D.; Sathish, S.; Hammond, R.; Marquis, M.; King, J. Offshore Wind Market Report: 2023 Edition; National Renewable Energy Laboratory (NREL): Golden, CO, USA, 2023. [Google Scholar]
  77. Zhang, J.; Wang, H. Development of offshore wind power and foundation technology for offshore wind turbines in China. Ocean. Eng. 2022, 266, 113256. [Google Scholar] [CrossRef]
  78. Hughes, L.; Longden, T. Offshore wind power in the Asia-Pacific: Expert elicitation on costs and policies. Energy Policy 2024, 184, 113842. [Google Scholar] [CrossRef]
  79. Frederiksen, R.D.; Bocewicz, G.; Radzki, G.; Banaszak, Z.; Nielsen, P. Cost-Effectiveness of Predictive Maintenance for Offshore Wind Farms: A Case Study. Energies 2024, 17, 3147. [Google Scholar] [CrossRef]
  80. Soares-Ramos, E.P.P.; de Oliveira-Assis, L.; Sarrias-Mena, R.; Fernández-Ramírez, L.M. Current status and future trends of offshore wind power in Europe. Energy 2020, 202, 117787. [Google Scholar] [CrossRef]
  81. Chung, C.; Lee, J.; Yang, J.S. National offshore wind strategy for late-mover countries. Renew. Energy 2022, 192, 472–484. [Google Scholar] [CrossRef]
  82. Gkeka-Serpetsidaki, P.; Skiniti, G.; Tournaki, S.; Tsoutsos, T. A Review of the Sustainable Siting of Offshore Wind Farms. Sustainability 2024, 16, 6036. [Google Scholar] [CrossRef]
  83. National Energy Administration. Transcript of the National Energy Administration’s Online Press Conference in the Third Quarter of 2023. Available online: https://www.nea.gov.cn/2023-07/31/c_1310734825.htm (accessed on 8 August 2024).
  84. Perveen, R.; Kishor, N.; Mohanty, S.R. Off-shore wind farm development: Present status and challenges. Renew. Sustain. Energy Rev. 2014, 29, 780–792. [Google Scholar] [CrossRef]
  85. Wang, W.; Bai, Y. Investigation on installation of offshore wind turbines. J. Mar. Sci. Appl. 2010, 9, 175–180. [Google Scholar] [CrossRef]
  86. Lacal-Arántegui, R.; Yusta, J.M.; Domínguez-Navarro, J.A. Offshore wind installation: Analysing the evidence behind improvements in installation time. Renew. Sustain. Energy Rev. 2018, 92, 133–145. [Google Scholar] [CrossRef]
  87. Li, Y.; Liu, L.; Li, S.; Hu, Z.-Z. The Probability of Ship Collision during the Fully Submerged Towing Process of Floating Offshore Wind Turbines. Sustainability 2024, 16, 1705. [Google Scholar] [CrossRef]
  88. Rippel, D.; Jathe, N.; Becker, M.; Lütjen, M.; Szczerbicka, H.; Freitag, M. A review on the planning problem for the installation of offshore wind farms. IFAC-PapersOnLine 2019, 52, 1337–1342. [Google Scholar] [CrossRef]
  89. Van Lynden, C.; van Winsen, I.; Westland, C.; Kana, A. Offshore Wind Installation Vessels: Generating insight about the driving factors behind the future design. Int. J. Marit. Eng. 2022, 164, 221–236. [Google Scholar]
  90. Scheu, M.; Matha, D.; Hofmann, M.; Muskulus, M. Maintenance strategies for large offshore wind farms. Energy Procedia 2012, 24, 281–288. [Google Scholar] [CrossRef]
  91. Yan, R.; Dunnett, S.; Jackson, L. Impact of condition monitoring on the maintenance and economic viability of offshore wind turbines. Reliab. Eng. Syst. Safe 2023, 238, 109475. [Google Scholar] [CrossRef]
  92. Kou, L.; Li, Y.; Zhang, F.; Gong, X.; Hu, Y.; Yuan, Q.; Ke, W. Review on monitoring, operation and maintenance of smart offshore wind farms. Sensors 2022, 22, 2822. [Google Scholar] [CrossRef] [PubMed]
  93. Rinaldi, G.; Thies, P.R.; Johanning, L. Current status and future trends in the operation and maintenance of offshore wind turbines: A review. Energies 2021, 14, 2484. [Google Scholar] [CrossRef]
Sustainability 16 07810 g001
Figure 1. Schematic diagram of offshore wind plant.
Figure 1. Schematic diagram of offshore wind plant.
Sustainability 16 07810 g001
Sustainability 16 07810 g002
Figure 2. (a) Vertical-axis wind turbines, (b) horizontal-axis wind turbines.
Figure 2. (a) Vertical-axis wind turbines, (b) horizontal-axis wind turbines.
Sustainability 16 07810 g002
Sustainability 16 07810 g003
Figure 3. The structure of (a) vertical axis wind turbine, (b) horizontal axis wind turbine.
Figure 3. The structure of (a) vertical axis wind turbine, (b) horizontal axis wind turbine.
Sustainability 16 07810 g003
Sustainability 16 07810 g004
Figure 4. Development of large offshore wind turbines in China.
Figure 4. Development of large offshore wind turbines in China.
Sustainability 16 07810 g004
Sustainability 16 07810 g005
Figure 5. The fixed offshore wind turbines of monopile type, jacket type, and tripod type [46].
Figure 5. The fixed offshore wind turbines of monopile type, jacket type, and tripod type [46].
Sustainability 16 07810 g005
Sustainability 16 07810 g006
Figure 6. Spar, semi-submersible, barge, and tension leg platforms for floating offshore wind power [46].
Figure 6. Spar, semi-submersible, barge, and tension leg platforms for floating offshore wind power [46].
Sustainability 16 07810 g006
Sustainability 16 07810 g007
Figure 7. By 2022, global offshore wind power. (a) Newly added installed capacity, (b) cumulative installed capacity [46].
Figure 7. By 2022, global offshore wind power. (a) Newly added installed capacity, (b) cumulative installed capacity [46].
Sustainability 16 07810 g007
Sustainability 16 07810 g008
Figure 8. (a,b) Split installation of offshore wind turbines, (c) the towage and installation of floating wind turbines, (d) the transportation and installation of integrated fixed offshore wind turbines.
Figure 8. (a,b) Split installation of offshore wind turbines, (c) the towage and installation of floating wind turbines, (d) the transportation and installation of integrated fixed offshore wind turbines.
Sustainability 16 07810 g008
Sustainability 16 07810 g009
Figure 9. (a) Offshore wind power installation ship, (b) submarine cable-laying ship.
Figure 9. (a) Offshore wind power installation ship, (b) submarine cable-laying ship.
Sustainability 16 07810 g009
Sustainability 16 07810 g010
Figure 10. Developmental trend of offshore wind power.
Figure 10. Developmental trend of offshore wind power.
Sustainability 16 07810 g010
Table 1. Large offshore wind turbines and parameters.
Table 1. Large offshore wind turbines and parameters.
Production CompanyTurbine TypeTimeUnit CapacityBlade Length
Siemens Gamesa (Zamudio, Spain)SG14-222DDMay 202014 MW108 m
General Electric (Boston, MA, USA)Haliade-X202014 MW107 m
Vestas (Aarhus, Denmark)V236-15.0 MWFebruary 202115 MW115.5 m
Goldwind (Beijing, China)GWH252-16 MWJune 202316 MW123 m
Mingyang (Zhongshan, China)MySE 16.0-242August 202116 MW118 m
Table 2. Fixed wind turbines and corresponding parameters.
Table 2. Fixed wind turbines and corresponding parameters.
ProjectTypeTimeUnit Capacity
Huaneng Cangnan No. 2monopile type20238.5 MW
Ormondetripod type20125.0 MW
Rudongjacket type20102.5 MW
Table 3. Floating wind turbine and corresponding parameters.
Table 3. Floating wind turbine and corresponding parameters.
ProjectFoundation/Turbine TypeTimeUnit Capacity
Hywind Tampenspar type
Siemens (Zamudio, Spain)		August 20238.6 MW
WindFloat Atlanticsemi-submersible type
MHI Vestas V164-8.4 MW (Aarhus, Denmark)		20208.4 MW
FLOATGENbarge type
V164-10.0 MW (Aarhus, Denmark)		201810.0 MW
SBM Offshore and IFP Energies Nouvellestension leg type
SWT-8.0-154 (Zamudio, Spain)		20208.0 MW
Table 4. Floating wind turbines in China and corresponding parameters.
Table 4. Floating wind turbines in China and corresponding parameters.
ProjectFoundation TypeTimeUnit CapacityImpeller Diameter
Yinlingsemi-submersible type20215.5 MW158 m
Fuyaosemi-submersible type20226.2 MW152 m
Guanlansemi-submersible type20237.25 MW158 m
GuonengGongxiangsemi-submersible type20234.0 MW130 m
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Su, X.; Wang, X.; Xu, W.; Yuan, L.; Xiong, C.; Chen, J. Offshore Wind Power: Progress of the Edge Tool, Which Can Promote Sustainable Energy Development. Sustainability 2024, 16, 7810. https://doi.org/10.3390/su16177810

AMA Style

Su X, Wang X, Xu W, Yuan L, Xiong C, Chen J. Offshore Wind Power: Progress of the Edge Tool, Which Can Promote Sustainable Energy Development. Sustainability. 2024; 16(17):7810. https://doi.org/10.3390/su16177810

Chicago/Turabian Style

Su, Xing, Xudong Wang, Wanli Xu, Liqian Yuan, Chunhua Xiong, and Jinmao Chen. 2024. "Offshore Wind Power: Progress of the Edge Tool, Which Can Promote Sustainable Energy Development" Sustainability 16, no. 17: 7810. https://doi.org/10.3390/su16177810

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop