wind energy center university of massachusetts wind resource assessment patrick quinlan university...

Wind Energy Center

University of Massachusetts

Wind Resource Assessment

Patrick Quinlan

University of MassachusettsWind Energy Center

Environmental Business Council

December 17, 2009

Wind Energy Center

University of Massachusetts

Wind and the Turbine

• Performance

• Design– Force related to square

of wind speed

– Extremes affect ultimate loads

– Turbulence and means affect fatigue

32

2

1URPwind

UPPWT

2

2

1UCF

Wind Energy Center

University of Massachusetts

Time Scale of Winds

• Wind varies in time, space, direction

Wind Energy Center

University of Massachusetts

Wind Shear: Power Law

• Power law model

• Exponent of 1/7

often assumed, usually much higher

rr z

z

zU

zU

)(

)(

Wind Energy Center

University of Massachusetts

Wind Data Acquisition Systems

• Typical wind data collection system for resource measurement– Sensors + backups, at multiple heights– Tower– Data recorder (“Logger”); eg., UMass Minuteman– Quality Assurance -- eg., UMass AQUA– Data analysis and reporting

Wind Energy Center

University of Massachusetts

Sample Wind Data Acquisition System

Wind Energy Center

University of Massachusetts

Wind Sensors

• Cup anemometers - Frequency output

• Wind vanes - Voltage output

Maximum 40 anemometer and wind vane

Wind Energy Center

University of Massachusetts

Remote Sensing: SODAR and LIDAR

• Measures to high elevations without a tower• Measures Doppler shift reflected from density

inhomogeneities or particle reflections in atmosphere• Good height resolution

12

8

4

0

Win

d S

pe

ed

, m/s

750700650600550500Sample number

160m 130m 100m 70m 40m

Wind Energy Center

University of Massachusetts

Presentation of Averaged Data

• Time series of speed• Time series of direction• Wind frequency rose• Wind speed rose• Histogram of wind speeds• Turbulence intensity vs. wind speed• Wind shear profiles• Diurnal averages

Wind Energy Center

University of Massachusetts

Wind Roses

• Wind Frequency Rose– Fraction of winds from

direction sectors

• Wind Speed Rose– Mean wind speed from

each direction sector

0%

2%

4%

6%

8%

10%

12%

14%

16%N

NNE

NE

ENE

E

ESE

SE

SSE

S

SSW

SW

WSW

W

WNW

NW

NNW

Vane - ESI 19m Vane 1 - FAA 24 Vane 2 - FAA 37

0

4

8

12

16N

NNE

NE

ENE

E

ESE

SE

SSE

S

SSW

SW

WSW

W

WNW

NW

NNW

Direction Percentage Wind Speed, M/sec

Wind Energy Center

University of Massachusetts

Histograms

• Histogram of wind speedsWind Speed Distribution, Bishop & Clerks, Feb 2002

0%

2%

4%

6%

8%

10%

12%

14%

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 21

Speed Bins, M/sec

Per

cen

t

Anemometer 1 - 15m primary Anemometer 2 - 15m backup

Wind Energy Center

University of Massachusetts

Turbulence Intensity

• Turbulence intensity vs. wind speedTurbulence Intensity

0

0.5

1

1.5

2

2.5

0 5 10 15 20 25

Wind Speed (m/s)

Turb

ule

nce

Inte

nsi

ty

Anemometer 1 TI Anemometer 2 TI

Wind Energy Center

University of Massachusetts

Wind Shear

• Wind shear and wind shear models140

120

100

80

60

40

20

0

Hei

ght,

m

1086420Wind Speed, m/s

12:10 12:20 12:30 12:40 12:50 Pow er Law Log Law

Wind Energy Center

University of Massachusetts

Diurnal Averages Diurnal Averaged Wind Speed

7.1

7.2

7.3

7.4

7.5

7.6

7.7

7.8

7.9

8

8.1

0 3 6 9 12 15 18 21 24

Hour

Avg

. W

ind

Sp

eed

(m

/s)

Anemometer 1 Anemometer 2

Wind Energy Center

University of Massachusetts

Questions?

Patrick Quinlan

University of Massachusetts

Wind Energy Center

quinlan@ecs.umass.edu

413-545-0617