Kts | Mph | m/s | Km/h | Bft |
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Kts | mph | m/s | km/h | force |
Humedad: | %hum% |
Presión: | %baro% |
Lluvia hoy: | %dayrn% |
Radiación: | % % |
Indice UV: | % % |
Nivel cond: | ft m |
Orto |
Cenit |
Ocaso |
Aerolugo's test page |
Wind Energy Production Testpage |
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This is where it all begins, a wind distribution histogram. In plain words it is the number of hours wind has been blowing at each recorded speed. Speeds are in m/s. Data is showed on the left in table format, below on a bar graph: Note that in table title we say "annual". All the following process can be done in a monthly basis, but for statistical and production purposes it is better working with a whole year data set. A daily one would be nice to "ajaxize" and see in near real-time how the system perfoms. But (a big but...) WD does not offer these data in an easy format. This page is feeded by a manual datafile. It would be nice to have just daily and yearly tags of these values. Brian? ;) |
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The next step is needed for later calculations. We need total hours (all speeds) and accumulated frequencies (for each speed and total). Two interesting figures are derived from these calculations:
The observation period is just the number of days you have data for this study. Of course if you have a whole year data set it should read about 365 days. The average wind speed is the total accumulated frequencies divided bt total wind hours. So it is related to the observation period. This is just a pretty useless statistic data for your location, we cannot calculate wind energy production based on this figure, we will see why at the last step. |
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The power wind can produce is given by this formula: P = 1/2d * v^3 * A where: d = air density (about 1.225 kg/m3) v = wind speed in m/s A = area in m^2 So we can make another table with nominal windpower per square meter (shown on the left). If we multiply each nominal windpower by the number of hours the wind has blown at each speed, we get what is called Power Density, the maximum real wind energy available at our location. But wind flowing through a wind turbine experiments some deceletation and deviations. The Betz Law rules this establishing that only 16/27 (59%) of the total windpower can be extracted by a wind turbine. Now we are near our first goal, multiplying each Betz corrected power density (watts) by the hours wind has blown at each speed and adding it all, we get the max possible wind energy (watt*hours) our location can produce: Max wind energy: 184.98 KWh Max Usable Wind Energy: 109.14 KWh This value is is the max total wind energy your location can produce in the specified observation period. Below you can see this stage data on a graph. |
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But... (the last "but") the ideal turbine does not exist. All of them have loses due to frictions, heating, etc. In addition you have to take into account the turbine rotor diameter. Each wind turbine has a power chart showing how much power it is capable to give at each wind speed. So we can know the turbine energy production at this location, and compared to its rotor area max power density get the turbine efficiency. Select a turbine to reload the page with its data Turbine model: rated: W Turbine rotor area: 0 m2 Turbine max usable wind energy: 0 KWh Global Turbine efficiency: 0 % Turbine production: 0 KWh Daily average production: 0 KWh Monthly average production: 0 KWh |