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Buoyant Energy is a new approach to store electrical energy offshore and decentralized, based on the well-established technologies of pumped-storage hydropower. This paper focuses on the basic concept and deals with some key features this new storage solution provides. Subsequently to the explanation of the main functionality of the storage concept other important parameters like the efficiency (more than 80% are estimated), the storage capacity (approximately 1 MWh for a solution with the dimensions of 50 × 50 × 38 m) and the high adaptability that provides numerous possible locations are discussed. This is followed by a basic cost assessment which demonstrates the economic feasibility for three different scenarios. The results indicate, that the break-even point is reached between 5 and 30 years but in each case within the proposed lifetime of 50 years and more. The final case study evaluates the effects of integrating deep offshore wind power balanced by integrated Buoyant Energy units. The rising flexibility of the overall system and the direct conversion of the intermittent to a constant power source over a pre-determined period are some benefits as shown in the results.

This paper presents the offshore wind resource assessment and an offshore wind power plant optimization in the Gulf of Thailand (GoT). The Weather Research and Forecasting (WRF) atmospheric model, along with the NCEP/NCAR R2 reanalysis climatic database, are applied to create wind resource maps at 80 m, 100 m, and 120 m above mean sea level (amsl) in order to identify the potential surface areas for the development of offshore wind power plants. The predicted wind speeds are validated using observed wind speeds obtained from 13 met masts installed along the coastline of the GoT. Results show that the average annual mean wind speeds reach the range of 5.5–6.5 m/s in specific areas of the Bay of Bangkok, situated in the northern part of the GoT. Based on the results of the wind resource assessment and using computational fluid dynamics microscale wind flow modelings, a wind power plant optimization is performed. The technical power potential and a priority zoning for offshore wind power development is performed using wind turbine generators of 3.3–8.0 MW capacity. Depending on the wind turbine generator selected, it is found that 642–924 MW of capacity could be installed in the short-term planning; 2658 to 3825 MW of additional capacity could be added in the medium-term planning, and 2864 to 4120 MW of additional capacity in the long-term planning. These wind power plants would have an annual energy production in the order of 5.6–8 PWh in the short-term, an additional 23 to 33 PWh in the medium-term, and an additional 25 to 36 PWh in the long-term, thus avoiding CO2eq emissions in the order of 3–4.5 million tons CO2eq per year in the short-term, 13 to 18 million tons in the medium-term, and 14 to 20 million tons in the long-term. In total, depending on the wind turbine generator selected, wind power plants in the GoT could have a total installed capacity of 6000 to over 8000 MW, would generate between 50 and 75 PWh of energy per year, while avoiding emissions of 30–40 million tons CO2eq per year.

The Naturstromspeicher in Gaildorf is a natural energy storage plant, combining a pumped storage hydro-electric power station with a wind farm. The pilot project, in a rural district of Baden-Wurttemberg in the south of Germany, uses pumps from an international technology group and is the first of its kind in the world.

The optimum configurations of photovoltaic-micro wind hybrid power systems with battery storage are determined for 12 low windy locations in the Indian western Himalayas which will provide inputs to formulate a policy for the renewable energy based hybrid systems in the region. The objective is to utilize the available wind resource to supplement the solar resource for improving reliability and minimizing energy storage requirements of hybrid systems. In the analysis 7 micro turbines ranging from 1 kWp to 5 kWp are considered. The solar and wind resource assessment of the region shows good solar resource of 4.11–5.24 kWh/m2/day but low wind resource with wind speeds ranging from 2 to 3.6 m/s. However, wind speeds more than 5 m/s are also available for about 1000 h annually indicating potential for small wind power generation. The feasibility analysis is carried out for 12 locations using measured data for one location and NASA satellite data for other 11 locations. A 1 kWp micro-wind turbine with cut in speed of 2 m/s is found to generate maximum energy annually for these locations for a typical load. The methodology can be used for identifying optimum micro-wind PV hybrid systems for low wind locations worldwide.

The search for renewable energy sources is becoming something of great importance in the face of conventional energy sources. Clean and renewable production systems is gaining incentive to search for pieces of institutions and the government, especially the sources like the sun and the wind. There are plenty of both sources throughout the Brazilian territory and its use becomes interesting to isolated regions due to lack of network installation that enables access to electricity. This study investigates the production of energy from a hybrid system composed of photovoltaic panels and a wind turbine. These systems are adequate to meet the energy needs of isolated areas due to the high cost of electrification places with low demand and difficult to access. The project was developed at the Center of Alternative Energy and Renewable - NEAR Rural Energizing Laboratory of the Department of UNESP Rural Engineering, Faculty Agricultural Sciences, Lageado Experimental Farm, located in Botucatu, Sao Paulo, Brazil, which was used three photovoltaic I-100 Isofoton with nominal power of 100Wp each, for a total installed 300Wp and a wind turbine AIR X-rural model SOUTHWEST WINDPOWER with nominal power of 400 W, which was obtained for a year energy production data using this system. In general, energy production ranged from 34.8 to 209 watts hybrid photovoltaic system and the wind. It was possible to observe the complementary mode of energy production systems analyzed, since the photovoltaic panels have higher yield during the day, while the wind turbine has energy production at night.

Today, electric power generated from renewable energy sources accounts for a large share of the Chinese power system. By the end of 2015, the total wind power installed capacity had reached 129 GW , ranking wind as the second largest power source following thermal power in some regions of China.

This paper summarizes the control design work that was performed to optimize the controller of a wind turbine on the WindFloat structure. The WindFloat is a semi-submersible floating platform designed to be a support structure for a multi-megawatt power-generating wind turbine. A controller developed for a bottom-fixed wind turbine configuration was modified for use when the turbine is mounted on the WindFloat platform. This results in an efficient platform heel resonance mitigation scheme. In addition several control modules, designed with a coupled linear model, were added to the fixed-bottom baseline controller. The approach was tested in a fully coupled nonlinear aero-hydroelastic simulation tool in which wind and wave disturbances were modeled. This testing yielded significant improvements in platform global performance and tower-base-bending loading.

In recent years more attention has been paid to renewable and clean sources of energy like wind. Due to the uncertainties related to wind turbines, issues of energy storage are significant. One of the most appropriate methods of energy storage is the production of hydrogen. The main aim of this paper is to investigate the capability of wind energy for producing hydrogen in the south eastern province of Sistan & Baluchestan in Iran. This paper analyzes four different wind turbines with a capacity of 300–900 kW in five locations, in Dalgan, Lutak, Mil-Nader, Nosratabad and Zahedan. In this study, two approaches were used; the actual average wind turbine power and the Weibull. It was found that EWT Directwind 500/54 provides the best capacity factor among all examined turbines with the highest value of 50.77% for the station at Lutak. Additionally, the highest energy production was from the AWE 52-900 wind turbine with an annual production of 2462.5 MWh. A wind-hydro system consisting of a power controller, a high efficiency rectifier, and an alkaline electrolyzer was considered. The proposed conversion system resulted in a linear relationship between generated wind turbine energy and the amount of hydrogen produced. Therefore, the highest amount of yearly hydrogen production (39.82 ton-H 2 ) is related to the largest examined wind turbine, installed in the station at Lutak.

The paper is devoted to offshore wind and wave power plants as an alternative to fossil hydrocarbon power engineering. It reports classifications and an analytical survey of the state-of-the-art of main types of offshore wind and wave turbines. The features of horizontal and vertical axes turbines constructions are described. Comparison of these two types of turbines has revealed the vertical axes design advantage since their height is two to three times less and its stability, accordingly, is higher. This allows expensive concrete tower constructions to be avoided and floating pontoons to be used, which is especially important for deep-water areas. The advantages of a two-contour wind turbine consisting of a fixed stator and a rotor directly connected with an electrical generator are highlighted. Due to the special “soaring in air” block construction of the turbine, the pressure on the seabed foundation is considerably reduced, allowing all the supporting structure for a floating pontoon to be replaced. The designs of wave turbines with direct and indirect operation are considered as well, the principles of harnessing marine wave energy are discussed and industrial prototypes of power plants of foreign firms are presented. With the help of analytical expressions, the evaluation of power performances is executed and a comparison of the power density criterion of wave energy with other kinds of renewable energy is indicated. It appears that the energy density of sea waves is an order greater of similar magnitude of wind and solar energy. On the basis of the idea of floating structures, the principles of designing hybrid and cluster offshore wind and wave power stations are suggested, where, with the help of power electronics and information technology, the electric energy of separate turbogenerators is integrated into a marine power pool system with HVDC underwater cable transmission to the consumers of a continental zone.

The potential of hybrid wind/solar energy system in the west coast area of Saudi Arabia is analyzed in this paper. The investigation puts emphasis on the energy production and cost of energy from both wind turbine and photovoltaic (PV) in the hybrid system. Unmet electric load and excess electricity are taken into consideration. The annual average solar irradiation and wind speed considered in this study are 5.95 kWh/m 2 /day and 3.53 m/s, respectively. MATLAB and HOMER software are used to perform the technical and economic analyses of the hybrid system. As indicated from the simulation results, the PV array shares more electricity production than the wind turbine generator if both wind turbine and PV array are utilized in the wind/solar hybrid system with the same sizes. The wind levelized cost of energy is $0.149/kWh, which is more expensive than the solar energy of $0.0637/kWh. The energy cost of the hybrid system is dominated by battery and wind turbine expenses.

This study analyzes the wind energy resources on Phuquoc Island, Vietnam. Daily wind data are collected from 2005 to 2011 in this study. The annual mean speed and power density are 6 m/s and 355 W/m2, respectively. Results show that more than 35% of the wind energy comes from the northwest. In this study, a 75 MW wind farm with 25 wind turbines is simulated by using the WAsP 10 program. The wind farm can produce over 189.636 GWh annually. In addition, the effects of wind disturbance and three-phase short circuit of the grid are analyzed using the ETAP 7.0 program.

Wind power technology is now a reliable electricity production system. It presents an economically attractive possible solution for the continuously increasing energy demand of Lebanon. However, the stochastic behavior of wind speed leads to significant disharmony between wind energy production and electricity demand. Hence, the prospect of creating a combined wind-hydro energy station is found to be a vital issue. This paper is an attempt to analyze the design of a pumping station and the performance of a hybrid wind-hydro power plant, in two dams in Lebanon (Quaraoun and Chabrouh), in order to choose the most suitable dam to store the energy surplus produced by wind power at night. An evaluation of the amount of water that could be pumped in both dams and the energy that could be produced from the stored electricity surplus are carried out in this paper, in order to select the most suitable dam to implement the hydro pumped storage power plant and store the electricity surplus. It is shown that the energy that could be produced in the dam of Chabrouh varies between 17 MWh and 698 MWh, while in the dam of Quaraoun is between 17 MWh and 768 MWh. An analysis of the cost of the energy produced by wind turbines per kWh and the produced water per m3 are carried out in this paper as well.

With the advent of a more severe energy crisis and environment contamination, wind energy, as one of the green and renewable energy resources, has attracted more and more attention worldwide [1], [2]. According to statistics issued by the Global Wind Energy Council (GWEC), by the end of 2014, the global installed capacity had reached 360,000 MW, while the installed capacity in China accounted for 114,763 MW, nearly one third of the total, as illustrated in Fig. 1. Meanwhile, it is envisioned in 2050 Blueprint of Wind Power Development in China that by the years 2030 and 2050, the scale of installed capacity will exceed 4 × 105 MW and 106 MW, respectively, so as to meet 8.4% and 17% of the demand for electricity nationwide, enabling wind energy to be one of five main energy resources.

This study investigates the challenges and opportunities facing the installation of a hybrid hydrogen-renewable energy system in a remote island area disconnected from any main power grid. Islands with strong wind energy potential have the potential to become self-sufficient energy generating hubs that may even export electricity or hydrogen. This study has tested whether the combination of wind and hydrogen can replace a diesel generator on one of the Faroe Islands, Mykines. The comparison is based on an evaluation of each power system's costs, efficiency, environmental impact and suitability for the Mykines. The findings from this research can help inform those seeking to design 100% renewable energy systems for remote areas, and in particular islands. Furthermore, our comparison has value for those seeking to optimize the integration of wind turbines with hydrogen energy systems.

The combination of wind and pumped storage is a useful method to compensate the fluctuation of wind power generation, which would exploit the abundant wind potential and increase wind power penetration. Taiwan Power Company (TPC) develops renewable energy actively in recent years. Moreover, TPC has started planning a high penetration wind power system and building offshore wind farms around the coast of Zhangbin, Yunlin and Penghu. The target of the offshore wind power installed capacity is up to 3 GW by 2025. However, the integration of the large scale of wind power would give huge challenges to the system operator because wind is randomly characterized. In this study, after high penetration wind power is integrated, the impacts of system frequency and the dispatch of conventional units will be discussed. Additionally, the hybrid system combing wind power with pumped-storage will be planning to reduce the effect of system frequency.

Wind energy is the world's fastest growing energy source. Specifically in the recent decade, offshore wind energy is the technology that has developed the fastest due to the stronger and stable winds produced at sea and the huge areas where it can be employed. Electricity production from wind sources has seen high growth along with wind turbine capacity, foreseeing a linear evolution in the next decade. Additionally, it has been well demonstrated recently that the larger the power per wind turbine unit installed, the lower the levelized cost of energy. Second-generation high-temperature superconductor synchronous generators with direct-drive technology (2GHTSDDSG) for offshore wind energy applications have recently emerged as an alternative to consider instead of permanent-magnet direct-drive synchronous generators (PMDDSG), due to their lower dimensions and low weight per megawatt. This paper contains a detailed “cradle-to-gate” life-cycle assessment of the 15-MW 2GHTSDDSG and PMDDSG, using GaBi 6 commercial software and PE International Professional and Ecoinvent 2.2 databases, as a result of quantifying each component required for the production. After a detailed inspection of each component fabrication, conclusions and recommendations are obtained and presented.

The electricity production in the island of S. Vicente is based on fossil fuel and wind and, although there are significant wind resources, they are not fully used because of its intermittent nature. In a previous work, we proposed solutions to tackle this issue. Since this island does not have fresh water available, excess wind electricity can be provided directly to desalination units that can produce desalinated water to supply the population. Other solution studied previously was the use of desalinated water in a pumped hydro system to store the remaining excess wind electricity. In this paper, the scenarios modelled previously are updated with more recent data on energy and water consumption and the respective annual costs are estimated. The results show that with the current wind power and desalination capacity installed in S. Vicente, and with the installation of a pumped hydro system, it is possible to have, by 2020, more than 36% of electricity production from renewable energy sources, together with 59% of the water supplied to the population produced from wind electricity, with costs 10% lower than those forecasted for that year. If the installation of more wind power and desalination capacity is considered, renewable energy sources production can reach 78% (53% wind and 25% hydro), with 93% of wind desalinated water, with about 20% decrease of costs in relation to those predicted for 2020.

Grid integration of wind power plants is complicated by wind variability and the technical characteristics of wind generators. The generation mix is evolving in today?s power system as conventional coal plants reach the end of their useful lives and are being displaced by cleaner technology such as wind and gas. At high levels of wind power penetration, the need for ancillary services increases, while the traditional resources that provide those services may become less available or economically feasible. Developing wind plant controls that allow performance more like that of conventional generation presents the opportunity for wind plants to provide a full range of ancillary services.

Crete Island is rich in renewable energy resources such as wind and solar. Likewise other European territories, renewable sources already are being explored for power production. Currently a large amount of wind energy on Crete is curtailed during certain daily periods as a result of reduced demand and minimum operating levels on thermal generators. Reducing wind power curtailment magnitude requires additional sources of flexibility in the grid, and electric energy storage is one of them. This paper address wind generation curtailment minimization through the storage of wind energy surplus. NaS (sodium sulfura) battery modelling is used in this study in order to shift wind generation from off-peak to on-peak through a technical-economic analysis, considering the total annualized cost of the storage system and the wind power curtailment based on an annual basis. The obtained results are based on real data, which includes Crete Island demand, renewable and conventional power generation.

In many countries fossil fuels are used as the main source to generate electricity, but due to the increase in energy consumption and the rapid depletion of the fossil fuel resources, the demand of alternate energy sources such as solar, wind or hydro power becomes high [1]. In this paper wind energy as an alternate energy resource for electric power generation is proposed in the form of a small wind farm for grid-connected application in Perlis Malaysia. The monthly wind speed data of Perlis which is the smallest state of Malaysia were measured and the wind mill parameters such as Air Density, Blade Length, Power Coefficient and Blade Length were calculated. The mechanical output power of the proposed wind turbine form is calculated to check out its performance and reliability. The results showed that the proposed wind energy power generating system is a good choice and can be implemented in Malaysia to provide enough power for small towns and rural areas.

This paper summarizes the main elements of provisional calculations and charts which are sufficient to justify proposals for construction of a wind power station with the pre-designed capacity of 50 MW. Methodology of wind power potential assessment at the point of construction is given, a layout of the construction site and the structure of a wind farm are developed. The offered below materials make it possible to perform the first stages of the design.

Being highly dependent of imported fossil fuels for its electricity generation, Thailand has an ambitious target for the integration of renewable energy in its electricity portfolio. This paper presents the offshore wind resource map of the Gulf of Thailand, with the objective of identifying the potential areas for grid connected offshore wind power development. A coupled numerical mesoscale atmospheric model and a microscale wind flow model, along with long-term global reanalysis climate data, are used to generate high resolution (200 m) wind resource maps at heights of 40 m, 80 m, 100 m, and 120 m above sea level. The offshore wind resource maps are validated using measured wind speeds obtained from 28 meteorological towers installed along the coast of the Gulf of Thailand. The site selection of potential areas for offshore wind power development is assessed with a multi-criteria decision making analysis. Specifically to the Bay of Bangkok, results show that a technical power potential in the order of 3000 MW could be developed to generate an annual energy production estimated in the order of 6 TWh/year. For the whole Gulf of Thailand, a technical power potential estimated at 7000 MW could generate in the order of 15 TWh/year.

The Venezuelan government has established more aggressive policies and incentives for renewable energy resources in recent time, especially in terms of wind power. Although several academic efforts to make publically available wind energy resource data in Venezuela, there is a lack of information in terms of local wind resource putting in risk development in areas where potential is good enough for commercial exploitation. The objective of this paper is to presents a very comprehensive wind resource assessment at Los Taques, Venezuela based on on-site observation anemometry. This is unique paper because it is the first ever wind energy assessment in Los Taques using hourly data recorded during three years in an on-site ground weather station contrary to studies based on daily values based on radar or satellite data. The applied methodology has been developed based on the characteristic of the data obtained from the on-site anemometry. Results of wind energy assessment and evaluations on a 100 MW wind farm shows the wind energy resource available in Los Taques is enough for commercial use and the results.

Wind energy generation has been projected to continue to play a key role in the decarbonization of developed global economies. Over the past decades, wind power generation has seen dramatic growth. More than 35 GW of new wind power capacity was brought online in 2013, making the global total installed power around 318 GW at the end of 2013, and the average annual growth rate over the last 10 years has been around 21% [1]. Onshore wind energy technology is well established and mature. As the onshore wind market approaches saturation, development programs of offshore wind farms are underway in many countries. In 2013, 1.63 GW of new offshore capacity was added, making an installed total of 7.05 GW. Figure 1 shows a global distribution of offshore wind power generation at the end of 2013 [2].

This paper describes essence of work of offshore wind power electric plants and crucial aspects of their building and operating. Prospects for development of global, European and domestic markets of offshore wind power industry have been delineated. A comparative analysis of environmental impact of an offshore and land-based 2MW wind power electric plant has been performed by using LCA method and Ecoindex – 99 (Ekowskaźnik 99) modelling.

The integration between renewable energy systems (RESs) and oil shale system ensures reliable power generation source with a competitive energy generation cost when compared to costs of conventional systems. In addition, this integration will prevent considerable amount of CO2 emissions. This study aims to determine the size of a grid-tied hybrid system in Al-Tafilah, Jordan that maximizes the yearly overall fraction of demand met with levelized cost of electricity (LCOE) equal to or lower than the local cost of electricity generation. In addition, the effect of the integration of lithium-ion batteries as short-term energy storage systems (ESSs) will be investigated in addition to the effect of carbon social cost on the economics of the system. The maximum FH by the hybrid system in Al-Tafilah is 97.2% with ESS and 96.9% without ESS where 70.4% of the demand is met by the 12 MW oil shale system; however, to achieve these fractions, enormous installed capacity of photovoltaic (PV) and wind is required where 99% of the energy production is excess and LCOE is larger than COEcon. The maximum FH with LCOE equals to COEcon can be achieved by 12 MW oil shale, 3.5 MW PV, and 6 MW wind turbines without ESS. Such size will have FH of 87.23%, capacity factor of 46.1%, RES fraction of 16.9%, net present value (NPV) of 34.8 million USD, and a payback period of 4.8 years.

Offshore wind farms gain momentum in the Atlantic Ocean with Jacket type of the Structures to support the wind turbines. The shallow water attracts the use of the Jacket structure piled into the seabed. The West Coast Pacific Ocean has deep water where the floating wind farms are recommended. Due to commercial and economic reasons, the offshore wind farm in the West Coast of the U. S. water has yet be initiated though it present important potential future opportunities. This paper addresses an innovative Offshore Wind Support Design with a floating vessel concept that avoids the need of the large crane supported and expensive day rate installation vessel. The specialty of this design is that it has two levels of telescopic configuration one for the floating vessel and the second for the turbine supporting tower. The installation vessel free configuration is the source of large cost reduction. The turbine is feasible to have pre-assembled, preinstalled and pre-commissioned in the controlled harbor facility on the shore before towed into the water. That increases the reliability of the system and reduces the construction time in the offshore. The most attractive result is that the capital cost per MW estimated is below the market price of the already installed and planned wind farms in the East Coast of the U. S.

In hydro power plants, the water is stored in dams to get more potential energy. This stored energy is used to hit the water turbines to drive the electrical generator. Similarly, the air can also be stored in a container to get more potential energy. This stored energy can be used further to hit the aero turbines to drive the electrical generator. The ducts are used to increase the velocity of the wind by venturi effect. The venturi effect is the jet effect; as with a funnel the velocity of the air decreases as the cross-sectional area increases, with the static pressure correspondingly increasing. The duct can be used to channelize the air and can be used to store in a container. As the wind moves through the duct, Wind pressure increases in the high cross-sectional area. If a container is placed at the high wind pressure end using a one-way valve, the air can be filled in it. The wind in the filled container can be further used to produce electricity by sending that wind through a regulator valve to a wind turbine.

To achieve 100 % of renewable energy, wind energy is indispensable. Especially offshore wind energy is playing an important role. For Germany, offshore wind energy is an essential part of the Energy Transition. The goal is to produce 6500 MW offshore wind energy in 2020.

Wind lens is a new type of wind power system consisting of a simple brimmed ring structure that surrounds the rotor causing greater wind to pass through the turbine. As a consequence, the turbine's efficiency of capturing energy from the wind gets dramatically increased. A Wind lens turbine can generate 2–5 times the power of an existing wind turbine given at the same rotor diameter and incoming wind speed. This fluid dynamical effect is also effective in the water. We have developed 1–3 kW Wind lens turbines and a 100 kW Wind lens turbine. In addition to the enhanced output power, Wind lens turbine is quiet. The technology is now used in an offshore experiment with a hexagonal float 18 meters in diameter set off the coast of Hakata Bay in Fukuoka City. Moreover, we are now pursuing larger size Wind lens turbines through multi-rotor design consisting of multiple Wind lens turbines in a same vertical plane to embody larger total power output.

Nowadays there is increased interest to incorporate energy storage technologies with wind turbines to mitigate grid-related challenges resulting from the intermittent supply from large-scale offshore wind farms. This paper presents a new concept to integrate compressed air energy storage (CAES) in floating offshore wind turbine (FOWT) structures. The FOWT support structures will serve a dual purpose: to provide the necessary buoyancy to maintain the entire wind turbine afloat and stable under different met-ocean conditions and to act as a pressure vessel for compressed air energy storage on site. The proposed concept involves a hydro-pneumatic accumulator installed on the seabed to store pressurized deep sea water that is pneumatically connected to the floating support structure by means of an umbilical conduit. The present study investigates the technical feasibility of this concept when integrated in tension leg platforms (TLPs). The focus is on the impact of the additional floating platform weight resulting from the CAES on the dynamic response characteristics and loads when exposed to irregular waves. A simplified model for sizing the TLP hull for different energy storage capacities is initially presented. This is then used to evaluate the dynamic response of nine different TLP geometries when supporting the NREL1 5MW baseline wind turbine model. Numerical simulations are carried out using the marine engineering software tool ANSYS Aqwa©. The work provides an insight on how TLP structures supporting wind turbines may be optimised to facilitate the integration of the proposed CAES concept. It is shown that it is technically feasible to integrate CAES capacities on the order of Megawatt-Hours within TLP structures without compromising the stability of the floating system; although this would involve a substantial increase in the total structure weight.

This study examines the effect of different wind turbine classes on the electricity production of wind farms in three areas of Australia, which present low, low to medium, and medium to high wind potential: Gingin, Armidale, and Gold Coast Seaway. Wind turbine classes determine the suitability of installing a wind turbine in a particulate site. Wind turbine data from six different manufacturers have been used. For each manufacturer, at lest two wind turbines with identical rated power (in the range of 1.5 MW–3 MW) and different wind turbine classes (IEC I, IEC II and/or IEC III) are compared. The results show the superiority of wind turbines that are designed for lower wind speeds (higher IEC class) in all three locations, in terms of energy production. This improvement is higher for the locations with lower and medium wind potential (Gingin and Armidale), and varies from 5% to 55%. Moreover, this study investigates the economical feasibility of a 30 MW wind farm, for all combinations of site locations and wind turbine models.

We give an overview of wind and ocean power generation methods. Wind generation is now an established large global business while ocean generation is still in the prototype stage of development. The most important parameter for commercial acceptance of these technologies is the levelized cost of electricity produced by them. We discuss areas necessary for further cost improvement of wind generation. We further discuss the types of electrical generators used in these applications.

The scope of this article is to investigate the effects of introducing a WP-PSS (Wind Powered Pumped Storage System) in isolated electricity systems assuming unfavourable conditions such as low onshore wind potential and low PSS head height. These disadvantages can be compensated with the installation of offshore wind parks, larger reservoirs and double penstocks to allow simultaneous water fall and pumping using pipes of the greatest diameter that are currently commercially available. With the above modifications, the energy efficiency of the WP-PSS improves while the installation costs rise. A new operation algorithm for the WP-PSS is created to fully utilize the capacity of the double penstock and ultimately maximise wind energy penetration. A case study for a WP-PSS on the island of Rhodes is presented in this paper. Despite unfavourable conditions, the WP-PSS model leads to the following results: • Annual wind energy penetration exceeds 50% of the annual electricity consumption. • The WP-PSS exhibits attractive financial induces without including any subsidies. The WP-PSS presented in this paper proved to be technically and economically feasible and revealed that WP-PSSs are a guaranteed choice for large scale penetration of R.E.S. in electrical systems.

This paper investigates the benefit of optimally integrating wind power in Kenya with pumped hydro storage. The approach includes development of an optimal control strategy to deploy paired wind and pumped hydro storage resources, for the Lake Turkana Wind Power project. The stochastic model, which maximizes expected revenue over the planning horizon, is developed taking into the consideration the structure and running of the Kenya electricity market. The 300 MW Lake Turkana Wind Power wind farm is simulated using wind speed data from Marsabit, which is in close proximity to the Lake Turkana region. From the simulation of the wind farm, we find that the daily pattern exhibited by the wind speeds, does not match the average daily load pattern. Pumped hydro storage reduces the systems total power output shortage by 46%. This approach to operation could alleviate the significant economic burden of the take-or-pay purchase agreement that led to the removal of financial backing of the project by the World Bank. The use of pumped hydro storage in conjunction with the wind farm is also found to increase the expected daily revenue of the wind farm by over ten thousand dollars.

The Jeju-Korea power system is a small-sized network with a system demand ranging from a autumn minimum of 350MW to a summer peak of 716MW. Because Jeju island is well exposed to north-east winds with high speed, applications to connect to Jeju power system are flooded. Considering physical/environmental constraints, Jeju Self-governing Province has also target for the wind power capacity of 1,350MW by 2020. It amounts to two or three times of Jeju average-demand power and wind power limit capacity announced by Korea Power Exchange (KPX) company. Wind farm connection agreements will be signed to maximize utilization of wind resource. In spite of submarine cable HVDC connected to Korea mainland, Jeju power system is independently operated by frequency and reserve control. This study reevaluates wind power limit based on the KPX criteria from 2016 to 2020. First of all wind power generation limit are affected by off-peak demand in Jeju power system. Also the possibility capacity rate of charging wind power output is evaluated by using energy storage system (ESS). As a result, in case of using 110MWh ESS, wind power limit increases 33~55MW(30~50% of ESS), wind power constraint energy decreases from 68,539MWh to 50,301MWh and wind farm capacity factor increases from 25.9 to 26.1% in 2020.

This study examined the wind energy potential and the economic viability of using wind turbine for electricity generation in selected locations along the coastal region of Ghana. The two-parameter Weibull probability density function was employed to analyze the wind speed data obtained from the Ghana Energy Commission. The energy output and unit cost of electricity generated from medium size commercial wind turbine models with rated powers ranging from 50 kW to 250 kW were determined. It was found that the wind resource along the coastal region of Ghana can be classified into Class 2 or less wind resource which indicate that this resource in this area is marginally suitable for large scale wind energy development or suitable for small scale applications and be useful as part of hybrid energy system. It was further observed that wind turbine with designed cut-in wind speed of less than 3 m/s and moderate rated wind speed between 9 and 11 m/s is more suitable for wind energy development along the coastal region of Ghana. Based on the selected wind turbine and assumptions used in this study, it was estimated that the unit cost of electricity varied between 0.0695 GH¢/kW h and 0.2817 GH¢/kW h.

Wind energy is achieving worldwide acceptance as the most appealing renewable resource. Due to its increasing portion of generation mix, wind farms are expected to play the role similar to the traditional power plants. Down the road toward this goal, the intermittency and uncertainty of wind are the two important factors that should be solved. Today, storage systems present a very interesting alternative to deal with the wind variability. Among various storage types, the hydrogen system is showing a promising future due to the high storage efficiency, low emissions, and wide applications. This paper presents a new coordination control scheme between the offshore wind farm and a hydrogen management system (HMS) for reducing the adverse impacts of wind variability. In the proposed scheme, the HMS is situated onshore to provide medium- to long-term energy balancing service. A supercapacitor bank is supplemented to the system for providing the short-term transient compensation. System configuration and control strategies are also presented. Simulation tests were conducted to verify the feasibility and effectiveness of the proposed control. Test results indicate that the proposed control makes the wind farm be more flexible to satisfy the grid operation.

Micro-scale/small wind turbines, unlike larger utility-scale turbines, produce electricity at a rate of 300 W to 10 kW at their rated wind speed and are typically below 30 m in hub-height. These wind turbines have much more flexibility in their costs, maintenance and siting, owing to their size, and can provided wind energy in areas much less suited for direct supply to the grid system. In the future under climate change, the energy landscape will likely shift from the present centralized electricity generation and delivery system to a more distributed and locally-generated electricity and delivery system. In the new system configuration, the role of relatively small sustainable electricity generators like small wind turbines will likely become more prominent. However, the small wind industry has been substantially slow to progress in Ontario, Canada, and there is much debate over its viability in a growing energy dependent economy. This study seeks to demonstrate the performance of a small wind turbine, and speculate on its potential power output and trend over Ontario historically over the last 33 years using the North American Regional Reanalysis (NARR) data. We assessed the efficiency of a Bergey Excel 1 kW wind turbine at the pre-established Kortright Centre for Conservation test site, located north of Toronto. Using a novel approach, the Bergey optimized power curve was incorporated with reanalysis data to establish power output across Ontario at three-hour resolution. Small turbine-based wind power around the Great Lakes and eastern James Bay increased during winter and fall, contributing up to 10% of the annual electricity demand in some regions in Ontario. We purport that increases in power output are driven by long-term reductions in sea and lake ice concentrations affecting atmospheric stability in surrounding regions.

>> This paper presents how to determine AEP(Annual Energy Production) by a small wind turbine inDuckjeokDo island. Evaluation of AEP is introduced to make a self-contained island including renewable energysources of wind, solar, and tidal energy. To determine the AEP in DuckjeokDo island, a local wind data is analyzedusing the annual wind data from Korea Institute of Energy Research firstly. After the wind data is separated in12-direction, a mean wind speed at each direction is determined. And then, a small wind turbine power curveis selected by introducing the capacity of a small wind turbine and the energy production of the wind turbineaccording to each wind direction. Finally, total annual wind energy production for each small wind turbine can be evaluated using the local wind density and local energy production considering a mechanical energy loss. Throughout the analytic study, it is found that the AEP of DuckjeokDo island is about 2.02MWh/y and 3.47MWh/yper a 1kW small wind turbine installed at the altitude of 10 m and 21m, respectively.

The utilization of high-altitude wind energy potential is a very attractive challenge. This is mainly due to the perspective of producing a large amount of electricity from a renewable source without using land, and having a very low visibility impact. The wind flow on the upper levels of the surface boundary layer is characterized by good power with low variability of wind conditions. Many innovative wind energy conversion flying devices are currently under development for this purpose. The technological solutions can be grouped in: • land installed generators (such as kite systems); • airship flying generators that can produce electricity far from the ground and are tethered by control wires, also used for the power transmission. Flying generators could prove more problematic in maintaining flying conditions due to their heavier weight, but they have the advantage that they can be moved to different locations with less intervention on the ground. Another important characteristic that the airship wind generator has, is the possibility of changing its height of operation very quickly and simply by using control cables. In this study, the operational scenario of the possible application of an innovative airship wind generator is studied and discussed. The possibility of adjusting the height of operation was analysed, and a methodology for choosing the optimal operating level was developed and applied to real test cases. Numerical and experimental techniques used to assess the characteristics of high-altitude winds, were also considered. Remotely sensed wind data obtained from a monostatic phased-array Doppler Sonic Detection and Ranging (SODAR) system were used to validate and tune the CFD model in one of the real-test cases investigated.

By 2020, it is expected that about 42 GW of offshore wind capacity will be built in European waters and 30 GW off the shore of China. According to the U.S. Department of Energy's National Offshore Wind Strategy, estimates for the United States are for approximately 10 GW of offshore capacity by then. This article gives an overview of current developments in this area from a power system point of view, namely, the offshore grid deployment that needs to accompany the offshore wind generation development. General ideas are given concerning political plans and related studies about technology issues, regulatory and market arrangements, and experience with offshore grid demonstration projects.

The Itamaracá island close to the state of Pernambuco in Brazil receives thousands of visitors during the period of long summer vacations (3 months), increasing the peak demand by a factor of almost 200%. The purpose of this work is to demonstrate that the offshore wind turbines can meet peak energy demand and at the same time reduce impact on conventional energy generation during other months as well. The method involves a nautical wind map at a height of 10 m, and extrapolating it for the desired height by logarithmic law. The annual wind energy output employs Weibull probability density function. The wind turbine siting is chosen with the aid of the nautical chart. The results obtained demonstrate that three wind turbines would generate about 30,000 MWh per year, sufficient for meeting electricity demand in the island.

Offshore wind farms are rapidly growing owing to their comparatively more stable wind conditions than onshore and land-based wind farms. The power capacity of offshore wind turbines has been increased to 5MW in order to capture a larger amount of wind energy, which results in an increase of each component’s size. Furthermore, the weight of the marine turbine components installed in the nacelle directly influences the total mechanical design, as well as the operation and maintenance (O&M) costs. A reduction in the weight of the nacelle allows for cost-effective tower and foundation structures. On the other hand, longer transmission distances from an offshore wind turbine to the load leads to higher energy losses. In this regard, DC transmission is more useful than AC transmission in terms of efficiency because no reactive power is generated/consumed by DC transmission cables. This paper describes some of the challenges and difficulties faced in designing high-power-density power conversion systems (HPDPCSs) for offshore wind turbines. A new approach for high gain/high voltage systems is introduced using transformerless power conversion technologies. Finally, the proposed converter is evaluated in terms of step-up conversion ratio, device number, modulation, and costs.

Renewable energy can play an important role in meeting the ultimate goal of replacing parts of fossil fuels to generate sustainable, inexhaustible, clean and safe energy. One of the promising applications of renewable energy technology is the installation of wind turbine that has been identified as having potential for wide-scale application in Hong Kong. Locally, wind turbines are seldom installed in building developments. The barriers include limited installation space available, the heavily obstructed external environments and noise and vibration problems. The apposite places for the installation would be on the roof/rooftop of low-rise buildings located in low-density zones. Relevant wind data and output power generated on-site, which may be quite site-dependent, are essential for modelling and evaluating the wind energy conversion system. Long-term measured wind data are crucial to the study of wind energy potential. This work studies the wind data and micro-wind turbine used in dense urban terrain and low-density area. Technical data including wind speed and output power were analyzed and reported. To achieve 1% of total building energy consumption generated from wind power, 17 micro-wind turbines are required to be installed in this institutional building located in low-density zone. Practical application: Wind turbine is one of the typical applications of renewable energy technology. However, micro-turbines are not popularly installed in building developments. This work analyses the measured wind data and the energy performance of micro-wind turbines installed in an institutional building. The findings provide the on-site measured data for design and assessment of micro-wind turbines installed in building blocks.

This work seeks to demonstrate the technical feasibility of offshore wind projects by calculating the preliminary estimate of wind energy production in the Brazilian marine environment, through a simplified methodology based on currently available data in a case study performed with the application of wind turbines. The Exclusive Economic Zone of Brazil is about 3.6 million km2, an area that can be harnessed for offshore wind energy production. The case study was conducted in Itamaraca Island, Pernambuco state with the aim of supplying the local energy demands. An analysis was carried out on the local wind conditions through an ocean wind map measured at a height of 10 m, and therefore, the wind speed was extrapolated to 90 m using the logarithmic law. The Weibull frequency distribution and the annual energy production were calculated. The results presented showed that three wind turbines at a rated power of 3 MW, including a calculated annual average wind speed of 7.15 m/s would generate around 30,000 MWh/year, which would be sufficient to ensure energy throughout the year in Itamaraca Island.

Jiangsu is one of the most prosperous provinces in China with the highest population density but a shortage of fossil fuel. However, wind energy is recognized as a sustainable resource which is abundant in Jiangsu Province. Even so, the fluctuation of wind power, offshore and non-grid-connected wind power systems are required to manage this fluctuation. In addition, hydrogen production using wind power is a new idea to increase the contribution of wind power. According to the current situation of Jiangsu Province and wind power technology in China, there are both advantages and disadvantages to the method of hydrogen production in using non-grid-connected offshore wind power.