Welcome to the world of wind energy. Wind Potential. Dr. D. V. Kanellopoulos OPWP Renewable Energy Training Program December 2016 Muscat, Oman

Transcription

1 Welcome to the world of wind energy Wind Potential Dr. D. V. Kanellopoulos OPWP Renewable Energy Training Program December 2016 Muscat, Oman 1

2 Solar radiation powers up the wind 2

3 Surface air temperatures on earth for January 3

4 Global Surface Winds latitude N NE N SW 0-30 N NE 0-30 S SE S NW S SE Predominate wind direction 4

5 Energy from the wind Air density depends on temperature and barometric pressure. The larger the diameter of the wt, the larger the gain. High speeds yield more energy Betz limit, named after german aerodynamist Albert Betz 5

6 BL=16/27 BL=0.593 Power coefficient % Cp TIP SPEED ratio, λ

7 Tip speed ratio, λ The tip-speed ratio, λ, or TSR for WTs is the ratio between the tangential speed of the tip of a blade and the actual velocity of the wind, The tip-speed ratio is related to efficiency, with the optimum varying with blade design. Higher tip speeds result in higher noise levels and require stronger blades due to large centrifugal forces. The tip speed of the blade can be calculated as ω times R, where ω is the rotor rotational speed in radians/second, and R is the rotor radius in meters.

8 Cp vs wind speed for various pitch angles Cp vs TSR(λ) for various pitch angles

9 Earth s climatic zones Meteorological parameters vary These affect wt performance and certification

10 Measuring wind speed & wind direction Wind speed Estimate the AEP in kwh, MWh, GWH Wind directions Design wind farm layouts in order to maximize energy output, minimize wake losses and land or sea use

11 Duration of wind measurements for safe AEP calculations? It cannot be less than a full year. More years reduce uncertainty in estimating AEP for the life time of a project which is 20years. Minimum duration period is normally obligatory by the regulatory authorities(e.g. RAE in GR) Malin Head Met station in Ireland

12 Duration of wind measurements for safe AEP calculations? 8.8 m/s ok E

13 Anemometers or wind sensors 1846-Thomas Romney Robinson, Ireland 3 cup 1926 John Patterson, a Canadian weatherman

14 The wind vector, in reality. Most measurement measure only the horizontal wind speed magnitude. W m/s U m/s V m/s The horizontal wind comprises of the U and V components of the true wind. This is used for site evaluation.

15 Anemometers types Rotating cup anemometers Hand anemometer. Battery needed. Total cup anemometer. No power needed!

16 Anemometers types Rotating propeller anemometers Hand anemometer. Battery needed. vane anemometer

17 Anemometers types Rotating propeller anemometers a W anemometer, suitable for any angle a U-V-W anemometer

18 Anemometers types Ultrasonic anemometers

19 Anemometers types Acoustic resonance anemometers

20 Anemometers types Hot wire anemometers

21 Anemometers types Laser Doppler anemometers Laser Doppler velocimetry (LDV), also known as laser Doppler anemometry (LDA), is the technique of using the Doppler shift in a laser beam to measure the velocity in transparent or semi-transparent fluid flows. The measurement with LDA is absolute, linear with velocity and requires no pre-calibration.

22 Anemometers types Thermal Field Variation anemometers, TFV This Design Idea describes a method by which you can detect and assess air or liquid fluid flow using an externally heated semiconductor diode. Airflow across the heated diode reduces its temperature, causing a variation in the diode's voltage drop. This principle is similar to that used in hot-wire anemometers.

23 Anemometers types Pressure tube anemometers

24 Technical specifications for cup anemometers For site assessment and measurement of power performance of wind energy power plants. Class A, B and S accredited according to IEC ( ) ISO , Measnet: Classcup Technical Data Meas range Meas. instability (w/o calibration) 0, m/s 0, m/s < 1% of meas. value or < 0,2 m/s Survival speed Permissible Ambient condit. 80 m/s (min. 30 minutes) C, all occurring situations of relative humidity (incl. dew moistening)

25 Technical specifications for cup anemometers Output signal Form rectangle Frequency m/s Amplitude is supply voltage, max. 15 V Load R > 1 kω (Push-pull output with 220 Ω in series) C < 200 nf (corresp. to length typical cable < 1km) Linearity Correlation factor r between frequency and wind speed y= 0,0462*f+0,21 typical r > (4 20 m/s) Starting < 0,3 m/s velocity Resolution 0,05 m wind run Distance <3m (acc. To ASTM D ), instrument constant respond to 63.2% of speed change

26 Anemometers types Wind direction sensors, wind vanes Artistic traditional wind vanes on house rooftops

27 Anemometers types Wind direction sensors, wind vanes Ice free wind vane

28 Technical specifications for wind vanes

29 Anemometers types Combined type anemometers, nick named airplane anemometers Used extensively in the 80 s and 90 s in Greece to verify sites

30 Anemometers types Combined type anemometers Not used for verified wind resource measurements

31 Anemometer towers H m AGL or ASL H minimum = or > than 10 m

32 Anemometer towers

33 Anemometer towers

34 Anemometer towers, with and without guy wires

35 Other necessary meteorological instrument used for wind resource evaluation, barometric pressure sensor

36 Other necessary meteorological instrument used for wind resource evaluation, thermometer Minimum Mean Maximum

37 Data Loggers, the brain of the measuring system

38 Data Loggers, the brain of the measuring system

39 Put your hard hats on. Lets put up one wind measuring system

40 Installation of a meteorological tower for wind energy evaluation How height we need the measurements? How many intermediate heights are necessary? Tubular or lattice towers? Team qualifications? Must follow standards in order to be accepted by permit procedure in the future

41 Installation of a meteorological tower for wind energy evaluation Ground preparation A 1:5000 scale map will give an indication of a suitable place, eye verification absolutely necessary. Permission will be necessary prior to erecting the tower. 63 m 46 m For a 60 m mast, areas in red must be cleared from vegetation if necessary 90 m

42 Installation of a meteorological tower for wind energy evaluation Ground preparation Final stage of anchor Final stage of anchor in solid rock

43 Installation of a meteorological tower for wind energy evaluation Ground preparation A 6.5 t hydraulic jack Mast base

44 Installation of a meteorological tower for wind energy evaluation Mast types Tubular type, e.g. D=152 mm Latice, e.g. L=500 mm

45 Installation of a meteorological tower for wind energy evaluation Ground preparation Mast alignment

46 Installation of a meteorological tower for wind energy evaluation How far do we place the instruments? Side arm, L=2500 mm

47 Installation of a meteorological tower for wind energy evaluation Instrument placements Top mast layout

48 Installation of a meteorological tower for wind energy evaluation Instrument s in place on top of the met mast

49 Installation of a meteorological tower for wind energy evaluation Area needed, personnel placements prior to erection

50 Installation of a meteorological tower for wind energy evaluation Erecting the mast At 45 degrees angle Final position At 30 degrees angle