Assessing Wind Potentials - Revision history

Wiki Gardener at 14:51, 14 October 2014

2014-10-14T14:51:32Z

Ranisha at 12:32, 29 August 2014

2014-08-29T12:32:44Z

Ranisha at 09:22, 1 August 2014

2014-08-01T09:22:47Z

Wiki Gardener at 14:23, 16 June 2014

2014-06-16T14:23:44Z

Wiki Gardener at 14:20, 16 June 2014

2014-06-16T14:20:15Z

Katharina Wiedemann at 09:45, 5 June 2013

2013-06-05T09:45:11Z

Show changes

Katharina Wiedemann: moved Assessing wind potentials to Assessing Wind Potentials

2012-05-15T13:28:54Z

moved Assessing wind potentials to Assessing Wind Potentials

Katharina Wiedemann at 13:28, 15 May 2012

2012-05-15T13:28:36Z

Show changes

Nils Marscheider at 08:18, 26 July 2011

2011-07-26T08:18:09Z

Nils Marscheider at 21:00, 25 July 2011

2011-07-25T21:00:00Z

@@ Line 1: / Line 1: @@
 = Overview =
 = Investigation of Available Wind Velocity Data for the Proposed Site<br/> =
@@ Line 21: / Line 29: @@
 Paul Gipe explains in his ''Guide to Small and Micro Wind Systems<ref>Gipe, P. (1999) Wind Energ Basics - A Guide to Small and Micro Wind Systems, Chelsea Green Publishing</ref>,'' that in case of micro wind systems, it is often better to install a small wind turbine and to monitor the output during the first year, than to conduct an own measurement: If the wind turbine output does not suitable values, the turbine could be resold easily as there is a large market for used small and micro wind turbines<ref>Gipe, P. (1999) Wind Energ Basics - A Guide to Small and Micro Wind Systems, Chelsea Green Publishing</ref>. Nevertheless as project size, related investments and – according to this – the responsibility of the project developer, increases, wind measurement becomes a central component of wind project development.
-[[Assessing_Wind_Potentials#toc|►Go to Top]]<br/>
+[[Assessing Wind Potentials#toc|►Go to Top]]<br/>
 == Site Selection and Wind Measurement in the Height of 10m<br/> ==
@@ Line 41: / Line 51: @@
 Costs of all described tools for wind measurement are listet in the following. The given prices are examples from two manufacturers of anemometers, vanes and data loggers, Ammonit and Thies.
 <u>Good experiences have been gathered with measurement devices of these providers:</u>
@@ Line 65: / Line 77: @@
 Including these informations and taking into account the analysis of the collected wind data at the height of 10 m the developers may decide, whether the project should be continued or not. If the measurement has revealed a suitable outcome the next measurement campaign has to be planned. In any other case the project will be ceased at this point. Speaking generally the outcome of measurement at 10 m height is a conceptional 'rated break point' applied in every large wind project.
-[[Assessing_Wind_Potentials#toc|►Go to Top]]
+[[Assessing Wind Potentials#toc|►Go to Top]]
 === Specification of Measurement Devices and Calibrated Sensors<br/> ===
@@ Line 77: / Line 91: @@
 *Notebook Computer
-[[Assessing_Wind_Potentials#toc|►Go to Top]]
+[[Assessing Wind Potentials#toc|►Go to Top]]
 <br/>
@@ Line 92: / Line 106: @@
 *Description of the direct surrounding of the measurement masts concerning potential obstacles for wind flow and estimation of roughness parameters.
-[[Assessing_Wind_Potentials#toc|►Go to Top]]
+[[Assessing Wind Potentials#toc|►Go to Top]]
 <br/>
@@ Line 104: / Line 118: @@
 *Wind measurement should result in a time series, which can be easily processed with the planning project WA<sup>S</sup>P. According to this an appropriate data format has to be chosen.
-<br/>
+[[Assessing Wind Potentials#toc|►Go to Top]]
 === Rating of the Wind Eata concerning the Quality of Wind Potential at the Site<br/> ===
@@ Line 124: / Line 138: @@
 The report recommends whether the project development should continued. Additionally recommendations for additional measurements at a height of 40 m is given.
-[[Assessing_Wind_Potentials#toc|►Go to Top]]
+[[Assessing Wind Potentials#toc|►Go to Top]]
 == Wind Measurement in Major Heights<br/> ==
@@ Line 138: / Line 154: @@
 It is possible to skip measurement at 10 m to safe time in project development. As measurement in 40 m causes high costs, the 10 m measurement should only be skipped, if initial data collection has revealed the general suitability of the site. As the availability of wind data for developing countries is rather low, a measurement campaign containing the two phases is recommended. After the measurement at 40 m is finished and data is analysed, developers decide again, whether the project should be continued or ceased.
-[[Assessing_Wind_Potentials#toc|►Go to Top]]
+[[Assessing Wind Potentials#toc|►Go to Top]]
 === Identification of Measurement Placements<br/> ===
@@ Line 152: / Line 170: @@
 The installation of masts and equipment and the conduction of wind measurement and data analysis is conform to the implementation of the first measurement phase.
-[[Assessing_Wind_Potentials#toc|►Go to Top]]
+[[Assessing Wind Potentials#toc|►Go to Top]]
 === Data Analysis and Forecasting of Wind Energy Yield<br/> ===
@@ Line 174: / Line 194: @@
 To evaluate the energy yield of the specific turbines within a wind park a project layout is generated: The potential decrease of annual energy yield for specific turbines is calculated considering the effects of shading between the turbines. This model calculations are used to generate proposals for the conduction of a feasibility study. The final report of the measurement campaign contains the outcome of the model calculations as well as a recommendation, whether the project should be continued or ceased.
-[[Assessing_Wind_Potentials#toc|►Go to Top]]
+[[Assessing Wind Potentials#toc|►Go to Top]]
 = Further Information =
@@ Line 181: / Line 203: @@
 *[[Estimation of Wind Energy Production|Estimation of Wind Energy Production]]<br/>
 = References<br/> =

@@ Line 21: / Line 21: @@
 Paul Gipe explains in his ''Guide to Small and Micro Wind Systems<ref>Gipe, P. (1999) Wind Energ Basics - A Guide to Small and Micro Wind Systems, Chelsea Green Publishing</ref>,'' that in case of micro wind systems, it is often better to install a small wind turbine and to monitor the output during the first year, than to conduct an own measurement: If the wind turbine output does not suitable values, the turbine could be resold easily as there is a large market for used small and micro wind turbines<ref>Gipe, P. (1999) Wind Energ Basics - A Guide to Small and Micro Wind Systems, Chelsea Green Publishing</ref>. Nevertheless as project size, related investments and – according to this – the responsibility of the project developer, increases, wind measurement becomes a central component of wind project development.
-<br/>
+[[Assessing_Wind_Potentials#toc|►Go to Top]]<br/>
 == Site Selection and Wind Measurement in the Height of 10m<br/> ==
@@ Line 61: / Line 61: @@
 <u>A wind regime with an average wind speed higher than 6 m/s can not be considered as a guaranty for economical feasibility as well:</u>
-The returns of a wind project as well as financing conditions are heavily influenced by national, regional and even local [[Political_Framework_Conditions_-_Wind_Energy|political framework conditions]]. Investigation and monitoring of the political framework conditions is a central task to prepare reliable statements about economical feasibility of the project.
+The returns of a wind project as well as financing conditions are heavily influenced by national, regional and even local [[Political Framework Conditions - Wind Energy|political framework conditions]]. Investigation and monitoring of the political framework conditions is a central task to prepare reliable statements about economical feasibility of the project.
 Including these informations and taking into account the analysis of the collected wind data at the height of 10 m the developers may decide, whether the project should be continued or not. If the measurement has revealed a suitable outcome the next measurement campaign has to be planned. In any other case the project will be ceased at this point. Speaking generally the outcome of measurement at 10 m height is a conceptional 'rated break point' applied in every large wind project.
-<br/>
+[[Assessing_Wind_Potentials#toc|►Go to Top]]
 === Specification of Measurement Devices and Calibrated Sensors<br/> ===
@@ Line 76: / Line 76: @@
 *additional equipment like cables
 *Notebook Computer
 <br/>
@@ Line 89: / Line 91: @@
 *Determination of geographic positions of measurement masts via GPS.
 *Description of the direct surrounding of the measurement masts concerning potential obstacles for wind flow and estimation of roughness parameters.
 <br/>
@@ Line 101: / Line 105: @@
 <br/>
 === Rating of the Wind Eata concerning the Quality of Wind Potential at the Site<br/> ===
@@ Line 118: / Line 124: @@
 The report recommends whether the project development should continued. Additionally recommendations for additional measurements at a height of 40 m is given.
-<br/>
+[[Assessing_Wind_Potentials#toc|►Go to Top]]
 == Wind Measurement in Major Heights<br/> ==
@@ Line 132: / Line 138: @@
 It is possible to skip measurement at 10 m to safe time in project development. As measurement in 40 m causes high costs, the 10 m measurement should only be skipped, if initial data collection has revealed the general suitability of the site. As the availability of wind data for developing countries is rather low, a measurement campaign containing the two phases is recommended. After the measurement at 40 m is finished and data is analysed, developers decide again, whether the project should be continued or ceased.
-<br/>
+[[Assessing_Wind_Potentials#toc|►Go to Top]]
 === Identification of Measurement Placements<br/> ===
@@ Line 146: / Line 152: @@
 The installation of masts and equipment and the conduction of wind measurement and data analysis is conform to the implementation of the first measurement phase.
-<br/>
+[[Assessing_Wind_Potentials#toc|►Go to Top]]
 === Data Analysis and Forecasting of Wind Energy Yield<br/> ===
@@ Line 168: / Line 174: @@
 To evaluate the energy yield of the specific turbines within a wind park a project layout is generated: The potential decrease of annual energy yield for specific turbines is calculated considering the effects of shading between the turbines. This model calculations are used to generate proposals for the conduction of a feasibility study. The final report of the measurement campaign contains the outcome of the model calculations as well as a recommendation, whether the project should be continued or ceased.
-<br/>
+[[Assessing_Wind_Potentials#toc|►Go to Top]]
 = Further Information =
 *[[Portal:Wind|Wind Portal on energypedia]]<br/>
-*[[Estimation_of_Wind_Energy_Production|Estimation of Wind Energy Production]]<br/>
+*[[Estimation of Wind Energy Production|Estimation of Wind Energy Production]]<br/>
 <br/>

@@ Line 8: / Line 8: @@
 <u>In case an open access atlas for regional or national wind velocity has been prepared, it probably is available at the following websites:</u>
 *[http://130.226.17.201/side.php?nummer=11 winddata.com]
-*[http://swera.unep.net/ UNEP Solar and Wind Energy Resource Assessment (SWERA)]
+*[http://en.openei.org/apps/SWERA/ UNEP Solar and Wind Energy Resource Assessment (SWERA)]
 <br/>
@@ Line 57: / Line 57: @@
 Based on the analysis of wind conditions in the height of 10 m, a first reliable estimation of the economical feasibility of the wind park at the proposed site can be worked out.
 An average wind velocity of 6 m/s at a height of 10 m is generally considered as a guiding value for a suitable wind project. The necessary wind conditions for a specific wind project can deviate from this: If the costs of alternative electricity sources is comparatively high, a wind project could be economically viable at average wind speeds below 6 m/s.
 <u>A wind regime with an average wind speed higher than 6 m/s can not be considered as a guaranty for economical feasibility as well:</u>
-The returns of a wind project as well as financing conditions are heavily influenced by national, regional and even local [[Political Framework Conditions - Wind Energy|political framework conditions]]. Investigation and monitoring of the political framework conditions is a central task to prepare reliable statements about economical feasibility of the project.
+The returns of a wind project as well as financing conditions are heavily influenced by national, regional and even local [[Political_Framework_Conditions_-_Wind_Energy|political framework conditions]]. Investigation and monitoring of the political framework conditions is a central task to prepare reliable statements about economical feasibility of the project.
 Including these informations and taking into account the analysis of the collected wind data at the height of 10 m the developers may decide, whether the project should be continued or not. If the measurement has revealed a suitable outcome the next measurement campaign has to be planned. In any other case the project will be ceased at this point. Speaking generally the outcome of measurement at 10 m height is a conceptional 'rated break point' applied in every large wind project.
@@ Line 136: / Line 136: @@
 === Identification of Measurement Placements<br/> ===
 Based on the outcome of the first measurement, proposals for continuing the measurements are worked out.
 <u>Beside choosing the placements for the 40 m measurement, the following aspects have to be considered:</u>
@@ Line 173: / Line 173: @@
 *[[Portal:Wind|Wind Portal on energypedia]]<br/>
 <br/>

@@ Line 57: / Line 57: @@
 Based on the analysis of wind conditions in the height of 10 m, a first reliable estimation of the economical feasibility of the wind park at the proposed site can be worked out.
-An average wind velocity of 6 m/s at a height of 10 m is generally considered as a guiding value for a suitable wind project. The necessary wind conditions for a specific wind project can deviate from this: If the costs of alternative electricity sources is comparatively high, a wind project could be economically viable at average wind speeds below 6 m/s. <u></u>
+An average wind velocity of 6 m/s at a height of 10 m is generally considered as a guiding value for a suitable wind project. The necessary wind conditions for a specific wind project can deviate from this: If the costs of alternative electricity sources is comparatively high, a wind project could be economically viable at average wind speeds below 6 m/s.
 <u>A wind regime with an average wind speed higher than 6 m/s can not be considered as a guaranty for economical feasibility as well:</u>
@@ Line 136: / Line 136: @@
 === Identification of Measurement Placements<br/> ===
-Based on the outcome of the first measurement, proposals for continuing the measurements are worked out. <u></u>
+Based on the outcome of the first measurement, proposals for continuing the measurements are worked out.
 <u>Beside choosing the placements for the 40 m measurement, the following aspects have to be considered:</u>
@@ Line 170: / Line 170: @@
 <br/>
-== Further Information ==
+= Further Information =
 *[[Portal:Wind|Wind Portal on energypedia]]<br/>
@@ Line 176: / Line 176: @@
 <br/>
-== References<br/> ==
+= References<br/> =
 <references />
 [[Category:Wind]]

@@ Line 1: / Line 1: @@
-== Investigation of Available Wind Velocity Data for the Proposed Site<br/> ==
+= Overview =
-As a first step in assessment of wind potentials available data from conducted measurements or other sources has to be gathered.
+= Investigation of Available Wind Velocity Data for the Proposed Site<br/> =
 <u>In case an open access atlas for regional or national wind velocity has been prepared, it probably is available at the following websites:</u>
@@ Line 32: / Line 34: @@
 <br/>
 In case only scarse information about wind conditions at the site is available, wind speed measurements should be conducted at 10 m height as a pre-study. In this way costs for measurements are kept low, since the suitability of the site still has a speculative character. Wind speed is measured by anemometers, while information about wind directions is gathered by a vane. It is of essential importance to calibrate the anemometers before their application. For large wind projects calibration is often done by accredited institutes. Calibration has to be conducted according to international guidelines like the ISO 3966<ref>International Organization of Standardization (2008) ISO 3966:2008 Measurement of fluid flow in closed conduits -- Velocity area method using Pitot static tubes, retrieved 10.7.2011, [[http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=50626]]</ref>, IEA-Guidelines for calibration<ref>International Energy Association (1999) Recommended practices for wind turbine testing and evaluation - 11. Wind speed measurement and use of cup anemometry, retrieved 10.7.2011 [[http://www.ieawind.org/Task_11/RecommendedPract/11%20Anemometry_secondPrint.pdf]]</ref> or the standardized methods of the MEASNET-Group<ref>MEASNET Group (2008) Cup anemometer calibration procedure - Version 1, retrieved 10.7.2011 [[http://www.measnet.org/anocalib_updated2008.pdf]]</ref>.
 For the storage of the measured wind data a data-logger is necessary. This device is installed in a case at the lower part of the measurement mast. The data-logger is supplied with electricity by a battery or a PV-module combined with a small battery storage. Supply of the data-logger has to be very reliable, because loss of data will result, if the data-logger is out of electricity. To prevent thievery of the PV-Module it should be fixed at a higher point of the measurement mast.
@@ Line 38: / Line 40: @@
 Collected wind data should be read out regularly: The most comfortable read-out-method is realized by installing a mobile communication device to read out data from afar. Remote connection to the data-logger also allows observation of the measurement devices. However it is necessary to visit the site in periodically to inspect the mast and the measurement devices on-site.
 Costs of all described tools for wind measurement are listet in the following. The given prices are examples from two manufacturers of anemometers, vanes and data loggers, Ammonit and Thies.
 <u>Good experiences have been gathered with measurement devices of these providers:</u>
@@ Line 55: / Line 57: @@
 Based on the analysis of wind conditions in the height of 10 m, a first reliable estimation of the economical feasibility of the wind park at the proposed site can be worked out.
-An average wind velocity of 6 m/s at a height of 10 m is generally considered as a guiding value for a suitable wind project. The necessary wind conditions for a specific wind project can deviate from this: If the costs of alternative electricity sources is comparatively high, a wind project could be economically viable at average wind speeds below 6 m/s. A wind regime with an average wind speed higher than 6 m/s can not be considered as a guaranty for economical feasibility as well:
+An average wind velocity of 6 m/s at a height of 10 m is generally considered as a guiding value for a suitable wind project. The necessary wind conditions for a specific wind project can deviate from this: If the costs of alternative electricity sources is comparatively high, a wind project could be economically viable at average wind speeds below 6 m/s. <u></u>
 The returns of a wind project as well as financing conditions are heavily influenced by national, regional and even local [[Political Framework Conditions - Wind Energy|political framework conditions]]. Investigation and monitoring of the political framework conditions is a central task to prepare reliable statements about economical feasibility of the project.
@@ Line 118: / Line 122: @@
 == Wind Measurement in Major Heights<br/> ==
 As wind velocity normally increases with height the wind 10 m - measurement allows only estimation of wind velocity at hub height. In case the report of the first measurement has recommended to continue project development, a second measurement at major heights is implemented.
 Measurement at hub height would reveal the most reliable outcome. It is technical feasible to install measurement masts with heights of 100 m, but the related costs of measurement are very high. It is generally considered sufficient to conduct additional measurements at the height of 40 m. The gathered data of this measurement may be used for extrapolation of wind speeds at hub height with an appropriate reliability. The measurements at the height of 10 and 40 m have to be conducted at the same placements, because the increase of wind speed with height depends on the specific placement of the mast: within flat ground conditions without major obstacles the wind speed increase with height is less than at a placement with high roughness values. The difference in wind velocity at the heights of 10 and 40 m can amount 2 m/s at several sites. On the other hand a lower wind speed is measured at 40 m than at 10 m. Thus applying additional measurements at 40 m height is fundamental for generating reliable wind data.
 Measurement masts of 40 m height cost approximately 10000 €. Lattice towers have a better stability than masts consisting of tubes, but their price is significantly higher.
@@ Line 126: / Line 130: @@
 Measurement is conducted for minimum for one year again. As it is known, that wind energy yield can vary significantly between years and measurement of one year does not provide enough information to determine the representative average value for the site, which is necessary for reliable further calculations. To approximate this long-time average value for wind velocity, outcome of measurements are compared with wind data available for other sites. If the correlation of the different data sets is sufficient, it will be possible to deduct the amount of deviation between the long-time average value and the outcome of the measurements. In case no data is available for comparison, a rough approximation can be calculated using so-called „reanalysis wind-data“ from US National Center for Atmospheric Research and National Center for Environmental Prediction (NCEP/NCAR)<ref>US National Center for Atmospheric Research and National Center for Environmental Prediction (NCEP/NCAR)[[http://www.ncep.noaa.gov/ (accessed: July 2011)]]</ref>. These data sets are generated by global climate-models, which include global measurement data to compute wind velocity data for different sites.
 It is possible to skip measurement at 10 m to safe time in project development. As measurement in 40 m causes high costs, the 10 m measurement should only be skipped, if initial data collection has revealed the general suitability of the site. As the availability of wind data for developing countries is rather low, a measurement campaign containing the two phases is recommended. After the measurement at 40 m is finished and data is analysed, developers decide again, whether the project should be continued or ceased.
 <br/>
@@ Line 132: / Line 136: @@
 === Identification of Measurement Placements<br/> ===
-Based on the outcome of the first measurement, proposals for continuing the measurements are worked out. Beside choosing the placements for the 40 m measurement, the following aspects have to be considered:
+Based on the outcome of the first measurement, proposals for continuing the measurements are worked out. <u></u>
 *All partners and project developers agree to the choice of placements
 *40m-masts and equipment are available;
-permissions for the installation of the masts and the conduction of the measurement has been granted by local authorities
+permissions for the installation of the masts and the conduction of the measurement has been granted by local authorities.
 The installation of masts and equipment and the conduction of wind measurement and data analysis is conform to the implementation of the first measurement phase.
@@ Line 166: / Line 172: @@
 == Further Information ==
-*[https://energypedia.info/Portal:Wind Portal:Wind]<br/>
+*[[Portal:Wind|Wind Portal on energypedia]]<br/>
 == References<br/> ==

@@ Line 140: / Line 140: @@
 == References<br>  ==
-<references /><br><br>
+<references /><br>
 [[Portal:Wind]]<br>
 [[Category:Wind]]

@@ Line 42: / Line 42: @@
 A minimal measurement period of one year is needed to generate a complete survey of the local wind conditions. Seasonal variations can be captured only by such relatively long-term measurements.
-Based on the analysis of wind conditions in the height of 10 m, a first reliable estimation of the economical feasibility of the wind&nbsp;&nbsp; park at the proposed site can be worked out.
+Based on the analysis of wind conditions in the height of 10 m, a first reliable estimation of the economical feasibility of the wind&nbsp; park at the proposed site can be worked out.
 An average wind velocity of 6 m/s at a height of 10 m is generally considered as a guiding value for a suitable wind project. The necessary wind conditions for a specific wind project can deviate from this: If the costs of alternative electricity sources is comparatively high, a wind project could be economically viable at average wind speeds below 6 m/s. A wind regime with an average wind speed higher than 6 m/s can not be considered as a guaranty for economical feasibility as well: