Search results for "Shore"
showing 10 items of 263 documents
Assessment of the technical and economic potential of offshore wind energy via a GIS application: A case study for the Sicily Region according to Ita…
2015
This paper presents a technical and economic analysis of the possible exploitation of offshore wind resources using spatial analysis methods based on GIS tools. The study assessed the magnitude and distribution of the main constraints on installation of wind farms by taking into account the relevant technical factors and local laws on nature protection issues in a specific area, i.e., Sicily. Specific cost functions were defined for several components of the total cost of construction and maintenance of a wind farm. Several scenarios were implemented according to wind turbine size, hub height, total wind farm power, and distance from the coast, and the levelised production cost was assessed…
A two-stage fault detection and classification for electric pitch drives in offshore wind farms using support vector machine
2017
This article presents a two-stage fault detection and classification scheme, for induction motor drives in wind turbine pitch systems. The presented approach is suitable for application in offshore wind farms. The adopted strategy utilizes three phase motor current sensing at the pitch drives for fault detection and only when a fault is detected at this stage, features extracted from the current signals are transmitted to a central support vector machine classifier. The proposed method is validated in a laboratory setup of the pitch drive.
Wind Turbines to Power Telecommunication Systems: A Case Study in Sicily
2011
The ever increasing problems related to air pollution and the difficulties for power lines to reach inaccessible areas are pushing to find new solutions for powering telecommunications equipments (TLC). The renewable energy sys- tems, although relatively expensive, have the required characteristics. The purpose of this work is to find a solution based on a low power wind turbine to serve a real telecommunication site located near Palermo, the main city of Sicily (Italy).
Impact of Building Layouts on Wind Turbine Power Output in the Built Environment: A Case Study of Tsu City
2014
In city planning, it is important to consider the future growth of renewable energy systems in the built environment. Wind speed analysis in the built environment is very important for analysing the wind turbine performance installed in the built environment. In this work, building topologies / layouts in Tsu city are considered for investing the wind speed distributions and directions. Wind speed profile in the built environment are developed by using CFD-ACE+. This work focusses on the analysis of the wind speed directions and distribution characteristics for finding out the proper location of the wind turbines in the built environment. The wind speed profiles and their directions and win…
Collaborative innovation: the decade that radically changed drilling performance
2012
This article sheds light on key factors associated with innovations that are mainly based on experiential learning. The history of a company engaged in the offshore oil and gas industry exemplifies the points: Hitec started out as a small company with limited financial resources, but over a 10-year period, its innovations and improvements radically transformed offshore oil and gas drilling operations. An evolutionary methodological approach is balanced by theoretically informed analysis. A main finding is that customer–supplier interaction was crucial. Hitec's success, crowned by its eventual acquisition by American capital, can be attributed in part to the know-how and technology provided …
Second-order hydrodynamic effects on the response of three semisubmersible floating offshore wind turbines
2020
Abstract Floating structures have become the most feasible solution for supporting wind turbines when offshore wind project move to deeper water. In this paper, a hydrodynamic analysis of three different semisubmersible floating offshore wind turbines is carried out including second-order hydrodynamic effects. The three examined platforms are V-shaped semisubmersible, Braceless semisubmersible and OC4-DeepCwind semisubmersible and are used to support the NREL 5 MW reference wind turbine. The main objective of the present study is to investigate and compare the hydrodynamic response of the three different semisubmersible floaters in two water depths (100 m, and 200 m) under different load co…
Behavioural responses of breeding arctic sandpipers to ground-surface temperature and primary productivity
2021
Most birds incubate their eggs, which requires time and energy at the expense of other activities. Birds generally have two incubation strategies: biparental where both mates cooperate in incubating eggs, and uniparental where a single parent incubates. In harsh and unpredictable environments, incubation is challenging due to high energetic demands and variable resource availability. We studied the relationships between the incubation behaviour of sandpipers (genus Calidris) and two environmental variables: temperature and a proxy of primary productivity (i.e. NDVI). We investigated how these relationships vary between incubation strategies and across species among strategies. We also stud…
Transient response of a TLP-type floating offshore wind turbine under tendon failure conditions
2021
Abstract Among various types of floating offshore wind turbines (FOWTs), the tension leg platform (TLP) floating wind turbines have relatively small motions due to stiff tendons. Similar to TLP applications in the offshore industry, tendon failure may lead to deteriorated stability and large transient responses, which should be considered as part of accidental limit state (ALS) checks at the design stage of the TLP FOWTs. This paper takes the WindStar TLP system as a representative and investigates the transient effects of one-tendon failure on the system responses. A coupled numerical model is first established using the aero-hydro-servo-elastic simulation tool FAST. Subsequent numerical s…
Quantifying submarine groundwater discharge in the coastal zone via multiple methods
2006
Submarine groundwater discharge (SGD) is now recognized as an important pathway between land and sea. As such, this flow may contribute to the biogeochemical and other marine budgets of near-shore waters. These discharges typically display significant spatial and temporal variability making assessments difficult. Groundwater seepage is patchy, diffuse, temporally variable, and may involve multiple aquifers. Thus, the measurement of its magnitude and associated chemical fluxes is a challenging enterprise. A joint project of UNESCO and the International Atomic Energy Agency (IAEA) has examined several methods of SGD assessment and carried out a series of five intercomparison experiments in di…
Stressing sequence of steel cable-stayed bridges built by cantilevering
2015
The construction of cable-stayed bridges by cantilevering implies several changes of geometry, stress and strain patterns during the assemblage of segments. The main target to be satisfied in the construction process is the achievement of the required final geometry and of a convenient state of stress for self-weight and sustained loads. The sequence of stay stressing and the values of prestressing forces at each stage of segment assembling have the main role for reaching the desired result of design, due to the large redundancy of cable-stayed structures.Among the different procedures proposed in the literature for initial cable force determination, the Partial Elastic Scheme (PES) Method …