Shore Wind Research Articles

Micro-siting Wind Resource Assessment and Near Shore Wind Farm Analysis in Pakpanang District, Nakhon Si Thammarat Province, Thailand

This paper presents the micro-siting wind resource assessment and near shore wind farm analysis in Pakpanang district, Nakhon Si Thammarat province, southern Thailand. One year of observed wind speed and wind direction data from a 120 m met tower installed near the shoreline are analyzed in order to investigate the monthly mean wind speeds and dominant wind directions at the site. The observed wind data is used to develop a 20 m resolution microscale map of the study area in order to analyze several configurations of near shore wind farms in the range of 10 to 90 MW. To this end, annual energy productions (AEP), wake effects, and theoretical capacity factors (TCF) are estimated using WAsP. Results show that the monthly mean wind speeds at 120 m above ground level are in the range of 3.3 to 5.3 m/s. The dominant wind at the site are from the NEE and SSW directions. In terms of the near shore wind farm analysis, the maximum net AEP is approximately 170 GWh/year (90 MW wind farm scenario), while the corresponding wind farm's wake loss is 3.65%, which corresponds to a 21.3% wind farm TCF.

The Electrical Facility in Off -shore Wind Power Station of Kitakyushu City

The Electrical Facility in Off -shore Wind Power Station of Kitakyushu City

MCP방법을 이용한 장기간 풍속 및 풍력에너지 변동 특성 분석

Wind resource data of short-term period has to be corrected a long-term period by using MCP method that Is a statistical method to predict the long-term wind resource at target site data with a reference site data. Because the field measurement for wind assessment is limited to a short period by various constraints. In this study, 2 different MCP methods such as Linear regression and Matrix method were chosen to compare the predictive accuracy between the methods. Finally long-term wind speed, wind power density and capacity factor at the target site for 20 years were estimated for the variability of wind and wind energy. As a result, for 20 years annual average wind speed, Yellow sea off shore wind farm was estimated to have 4.29% for coefficient of variation, CV, and -9.57%~9.53% for range of variation, RV. It was predicted that the annual wind speed at Yellow sea offshore wind farm varied within .

Maintenance Planning with Prognostics for Systems Located In Various Places


 
 
 Predictive maintenance has been attracting researchers and industry in recent years, since maintenance and repair of assets is one of the most contributing factors of operating & support cost. Predictive maintenance proposes to maintain the assets only when necessary aiming to reduce the unnecessary repair and maintenance by monitoring the health of the assets. The expected time of the failure is estimated by analyzing the monitored signals and remaining useful life of the asset before failure is used to plan, get prepared and perform the maintenance. When one team is responsible for maintenance of systems that are located in various places, the travel time between these systems should also be incorporated in the maintenance planning. Off shore wind farms and railway switches are two examples of these systems. This paper presents formulation of the problem that incorporates travel times between systems and prognostics information obtained from each system.
 
 

Pole-mounted horizontal axis micro-wind turbines: UK field trial findings and market size assessment

This paper discusses the key findings of the pole-mounted turbine (2.5–6 kWp) component of the UK micro-wind trial. The real world performance of horizontal axis turbines is compared with yield estimates based on site wind speed prediction. The distribution of UK agricultural farms is overlaid with wind resource mapping to estimate the number of potential agricultural farm sites for micro-wind. The yield performance of turbines during the monitoring period was observed to be very close to that predicted by NOABL–MCS wind speed estimates. Based on an installation criterion of a maximum 12 year payback time, with a 6% discount rate and micro-generation feed in tariffs available, there are ∼87,000 farm sites for micro-wind in the UK. If 10% of these farms were to install micro-wind turbines (to a capacity of 48 kWp per farm) this would correspond to a capacity of 418 MWp, with an annual generation yield of 1025 GWh, comparable to that of a large, on shore wind farm in the UK. It should be noted that the feed in tariff considered in this paper is that available in the UK in 2011, which, at 26.7 p/kWh (∼30 Euro cents/kWh) represents a significant subsidy.

Affect Analysis of Power Grid Energy Quality for Coastal Wind Power Access

While the effect on the power grid have become increasingly prominent as the larger proportion of wind power in to the grid. It is needed to study the grid's ability of taking in wind power. One of the main issues which including harmonics, voltage fluctuation and flicker is the effect on energy quality when integrating the wind farms into power grid. The impact is related to the type of the wind Turbines, the wind farm scale, the short-circuit capacity of the grid and the line parameters. The mechanism of voltage fluctuation and harmonics caused by off shore wind farms is studied. The case of Zhejiang off shore wind-farm integration is studied and the index of Power Quality is given. Some effective measures to reduce the voltage fluctuation and flicker and harmonics are put forward, besides, using simulation software PSD-BPA to verify the effectiveness of reducing voltage fluctuation.

Current Status and Consideration of Off shore Wind Power Generation

Current Status and Consideration of Off shore Wind Power Generation

Evolution of the vertical profile and flux of large sea‐salt particles in a coastal zone

In the vicinity of the North Carolina Outer Banks we observed both steady onshore flow conditions and a continental air mass transition into a marine boundary layer. Using the CIRPAS Twin Otter aircraft, we measured changes in the column burden of sea salt as the air mass was advected out to sea. We also measured the flux of whitecap‐generated sea‐salt particles in neutrally stable atmosphere at wind speeds of 4, 8, and 12 m s−1. Production of salt particles as small as 0.27 μm in diameter was observed. Furthermore, we measured salt particle size distributions at various wind speeds during along shore wind and near steady state conditions. Using these measurements as a frame of reference, we discuss the very large differences in the reported size and flux of sea salt presented in the literature. The disagreement in reported salt fluxes is larger for smaller‐ sized particles (almost an order of magnitude) and is most likely due to assumptions made when the fluxes were computed, especially the particle dry deposition velocity and air mass history. However, for giant salt particles with short atmospheric lifetimes (>∼10 μm in diameter), there is general agreement between fluxes and size distributions measured in this study and previous ones. Reported salt particle size distributions in the literature also vary considerably under similar steady wind and stability conditions. From these and our results it is clear that no more than half of the variance in salt particle concentration can be explained by wind speed alone, suggesting that the idea of “steady state” in the marine boundary layer rarely exists at midlatitudes.

Variability of thermal structure off Georgia, winter 1978

Temperatures recorded over the Georgia shelf and at near-bottom locations on the slope are compared with records of thermocline elevation from inverted echo sounders on the slope and with shore wind observations, for the period January to April 1978. Both upwelling and downwelling events are observed. Upwelling events are associated with upwelling-favorable wind and/or Gulf stream frontal eddies. Strong upwellings are accompanied by risings of the thermocline over the slope, but some weaker eddies occur without noticeable thermocline disturbance. Downwelling events are associated with onshore meander crests of the Gulf Stream, and sometimes with downwelling-favorable wind. The influence of downwelling does not extend seaward of the upper slope. A long-term (1 month) variation of the thermal structure is observed at the shelf break and under the Gulf Stream. It is related to a filament of cold water on the slope, varying in path and size. This cold filament appears to be Antarctic Intermediate Water which is variably advected through the Straits of Florida. Theory suggest that the variability may be caused by changes in the thermocline depth and tilt across the Gulf Stream in response to transport fluctuations.

The speed and some other features of the sea-breeze Front at Madras

The speed with which the sea breeze advances inland at Madras under various meteorological conditions and Its dependence on the time of onset and depth of penetration are discussed in this paper, utilising the records for the year 1945 and 1946 of autographic instruments at three stations located at different distances from the coast. A velocity of 10-15 mph, a south southeasterly direction of the resultant wind, the months April to September and a time of onset during the early afternoon are favoured most by the sea breeze at Madras. The average speed of the sea- breeze front is found to be 37 mph. It is accelerated with depth of penetration inland independently of the wind speed. It varies with the hour of onset of the sea-breeze, being lowest during the epoch of maximum temperature. The variation of the ratio of the speed inland to that near the coast with time of onset and direction of the on-shore wind is investigated. The results are explained on t he basis of the temperature gradient and its variation with distance inland. The mean temperature drop and vapour pressure rise caused by the sea-breeze for different times of incidence and magnitudes of wind velocity in the various months have also been studied. The changes are maximum in the proximity of the epoch of maximum temperature and in the month of July in the year. The results of this study would help in anticipating with sufficient accuracy and sufficiently in advance for aviation needs the time of onset of the sea-breeze and the accompanying meteorological changes at the airfield at Meenambakkam given the time of incidence and the direction of the on shore wind earlier at a point closer to the coast.