Wind Resources 1: The European Wind Climatology

2018 ◽  
pp. 236-245
Author(s):  
Erik L. Petersen
Keyword(s):  
Wind Climatology ◽  
Wind Resources

U.S. Virgin Islands Wind Resources Update 2014

2014 ◽  
Author(s):  
J. Roberts ◽  
A. Warren
Keyword(s):  
Virgin Islands ◽  
Wind Resources

The Application of the Micro-Siting Technique in Tioman Island, Malaysia Using the RIAM-COMPACT Software

2014 ◽  
Vol 660 ◽  
pp. 745-749
Author(s):  
Rosly Nurhayati ◽  
Mohd Sofian
Keyword(s):  
Complex Terrain ◽  
Meteorological Data ◽  
Computational Prediction ◽  
Applied Mechanics ◽  
Eddy Simulation ◽  
Turbine Generators ◽  
Wind Turbine Generators ◽  
Large Eddy ◽  
Asean Countries ◽  
Wind Resources

ASEAN (Association of Southeast Asian Nations) countries may have a huge potential for utilizing wind energy as it requires little in the way of land. Land in these countries is very fertile and is used by other alternatives, therefore reducing its conduciveness for developing solar energy. The wind resources map is widely available for Laos, Vietnam, Thailand, Cambodia and Philippines but there is not much information about other ASEAN countries. Based on meteorological data, Tioman Island was selected as the area that had the best potential for installing wind turbines in Malaysia. A more detailed study was conducted using a CFD model for unsteady flow, known as the Research Institute for Applied Mechanics, Kyushu University, COMputational Prediction of Airflow over Complex Terrain (RIAM-COMPACT®) which is based on the Large-Eddy Simulation (LES) technique. Micro-siting technique is used as a tool for selecting appropriate point and an inappropriate point for locating wind turbine generators (WTGs) at Tioman Island, Malaysia. The suggested points for locating WTGs were shown based on the numerical results obtained from the calculation.

scholarly journals Advection-Based Adjustment of Radar Measurements

2012 ◽  
Vol 140 (3) ◽  
pp. 1014-1022 ◽  
Author(s):  
Tuomo Lauri ◽  
Jarmo Koistinen ◽  
Dmitri Moisseev
Keyword(s):  
Elevation Angle ◽  
Geographical Location ◽  
Ground Level ◽  
Limited Area ◽  
Similar Amount ◽  
Radar Measurement ◽  
Wind Climatology ◽  
Radar Measurements ◽  
Nwp Model ◽  
Adjustment Scheme

When making radar-based precipitation products, a radar measurement is commonly taken to represent the geographical location vertically below the contributing volume of the measurement sample. However, when wind is present during the fall of the hydrometeors, precipitation will be displaced horizontally from the geographical location of the radar measurement. Horizontal advection will introduce discrepancies between the radar-measured and ground level precipitation fields. The significance of the adjustment depends on a variety of factors related to the characteristics of the observed precipitation as well as those of the desired end product. In this paper the authors present an advection adjustment scheme for radar precipitation observations using estimated hydrometeor trajectories obtained from the High-Resolution Limited-Area Model (HIRLAM) MB71 NWP model data. They use the method to correct the operational Finnish radar composite and evaluate the significance of precipitation advection in typical Finnish conditions. The results show that advection distances on the order of tens of kilometers are consistently observed near the edge of the composite at ranges of 100–250 km from the nearest radar, even when using a low elevation angle of 0.3°. The Finnish wind climatology suggests that approximately 15% of single radar measurement areas are lost on average when estimating ground level rainfall if no advection adjustment is applied. For the Finnish composite, area reductions of approximately 10% have been observed, while the measuring area is extended downstream by a similar amount. Advection becomes increasingly important at all ranges in snowfall with maximum distances exceeding 100 km.

scholarly journals Evaluation and Analysis of Wind Resources in Jin-Jing-Ji Region of China

2011 ◽  
Vol 11 ◽  
pp. 836-842 ◽  
Author(s):  
Yang Hua ◽  
Yan Binghong ◽  
Qi Chengying ◽  
Chen Dan
Keyword(s):  
Wind Resources

scholarly journals The semiannual oscillation (SAO) in the tropical middle atmosphere and its gravity wave driving in reanalyses and satellite observations

2021 ◽  
Vol 21 (18) ◽  
pp. 13763-13795
Author(s):  
Manfred Ern ◽  
Mohamadou Diallo ◽  
Peter Preusse ◽  
Martin G. Mlynczak ◽  
Michael J. Schwartz ◽  
...  
Keyword(s):  
Gravity Wave ◽  
Gravity Waves ◽  
Wave Drag ◽  
Satellite Observations ◽  
Absolute Gravity ◽  
Data Sets ◽  
Background Wind ◽  
Wind Climatology ◽  
Basic Features ◽  
Semiannual Oscillation

Abstract. Gravity waves play a significant role in driving the semiannual oscillation (SAO) of the zonal wind in the tropics. However, detailed knowledge of this forcing is missing, and direct estimates from global observations of gravity waves are sparse. For the period 2002–2018, we investigate the SAO in four different reanalyses: ERA-Interim, JRA-55, ERA-5, and MERRA-2. Comparison with the SPARC zonal wind climatology and quasi-geostrophic winds derived from Microwave Limb Sounder (MLS) and Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) satellite observations show that the reanalyses reproduce some basic features of the SAO. However, there are also large differences, depending on the model setup. Particularly, MERRA-2 seems to benefit from dedicated tuning of the gravity wave drag parameterization and assimilation of MLS observations. To study the interaction of gravity waves with the background wind, absolute values of gravity wave momentum fluxes and a proxy for absolute gravity wave drag derived from SABER satellite observations are compared with different wind data sets: the SPARC wind climatology; data sets combining ERA-Interim at low altitudes and MLS or SABER quasi-geostrophic winds at high altitudes; and data sets that combine ERA-Interim, SABER quasi-geostrophic winds, and direct wind observations by the TIMED Doppler Interferometer (TIDI). In the lower and middle mesosphere the SABER absolute gravity wave drag proxy correlates well with positive vertical gradients of the background wind, indicating that gravity waves contribute mainly to the driving of the SAO eastward wind phases and their downward propagation with time. At altitudes 75–85 km, the SABER absolute gravity wave drag proxy correlates better with absolute values of the background wind, suggesting a more direct forcing of the SAO winds by gravity wave amplitude saturation. Above about 80 km SABER gravity wave drag is mainly governed by tides rather than by the SAO. The reanalyses reproduce some basic features of the SAO gravity wave driving: all reanalyses show stronger gravity wave driving of the SAO eastward phase in the stratopause region. For the higher-top models ERA-5 and MERRA-2, this is also the case in the lower mesosphere. However, all reanalyses are limited by model-inherent damping in the upper model levels, leading to unrealistic features near the model top. Our analysis of the SABER and reanalysis gravity wave drag suggests that the magnitude of SAO gravity wave forcing is often too weak in the free-running general circulation models; therefore, a more realistic representation is needed.

scholarly journals Financial Leverage and its Determinants in Companies Producing Electricity from Wind Resources in Latvia

2015 ◽  
Vol 27 (1) ◽  
pp. 29-39
Author(s):  
Viktorija Bobinaite
Keyword(s):  
Weighted Average ◽  
Economic Assessment ◽  
Electricity Sector ◽  
Analysis Method ◽  
Financial Leverage ◽  
Effective Tax Rate ◽  
Financial Ratio ◽  
Tax Rate ◽  
Significant Relationships ◽  
Wind Resources

Abstract The paper aims to analyse the development of the financial leverage and its determinants in companies producing electricity from wind resources in Latvia during 2005-2012. The financial ratio technique is used to compute the financial leverage in the companies and the regression analysis method is employed to determine the relationships between variables. The results of the analysis revealed that wind electricity generating companies use substantial share of debt and the financial leverage is increasing. Statistically significant relationships were found between the financial leverage and profitability of companies, their growth opportunities, collateral value of assets, size of the company and an effective tax rate. Results will be used to construct weighted average cost of capital (WACC) for the economic assessment of investment into wind electricity sector in Latvia.

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