1

Wind Energy in Vermont: A Meteorologist’s Perspective

NVDA Wind Study CommitteeBarton, VT

9/25/13

Dr. Jason ShaferAssociate Professor of Atmospheric Sciences

Lyndon State CollegeJason.Shafer@lyndonstate.edu

2

Annual Wind Resource Climatology

3http://www.windpoweringamerica.gov/images/windmaps/us_windmap_80meters.jpg

4http://www.windpoweringamerica.gov/images/windmaps/vt_80m.jpg

5http://www.northeastwind.com/resources/wind-resource-maps

6http://www.northeastwind.com/resources/wind-resource-maps

7http://www.northeastwind.com/resources/wind-resource-maps

8http://www.northeastwind.com/resources/wind-resource-maps

9

Seasonal and Diurnal Climatology

10

~15 Stations in the NEK10 with wind dataAll below 1400’ elevation

Newport

Island Pond

Lyndonville

11

Burlington Newport Lyndonville Island Pond Mt. Washington0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

45.0

8.16.7

5.2 4.8

39.3

Average Annual Wind Speed (2012)Sp

eed

(MPH

)

12

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec20.0

25.0

30.0

35.0

40.0

45.0

50.0

55.052.0

50.2

45.8

39.7

32.931.3

29.4

27.3

32.4

39.4

45.9

51.0

Mt. Washington, NH: Average Monthly Wind Speed (1982-2011)

MPH

13

Winter Spring Summer Fall4.00

5.00

6.00

7.00

8.00

6.96

7.57

5.89

6.23

Newport, VT (KEFK), 2012 Average Seasonal Wind W

ind

Spee

d (M

PH)

14

1:00 AM

3:00 AM

5:00 AM

7:00 AM

9:00 AM

11:00 AM

1:00 PM

3:00 PM

5:00 PM

7:00 PM

9:00 PM

11:00 PM4.00

5.00

6.00

7.00

8.00

9.00

10.00

Newport, VT (KEFK), Avg 2012 Diurnal Wind SpeedSp

eed

(MPH

)

15

Wind Rose climatology for Lyndonville, VT

Source: AWS True Wind

16

Carrera et al. 2009

Similar to Lyndonville, the two dominant wind directions are from the south and northwest.

Burlington, VT Wind Direction Frequency

17

Localized Effects

Wind Energy Production

312e pP C V AV

Wind energy production is very sensitive to small changes in wind speed, to the cube of the wind speed.

18

19

IPCC 2012

20

Fig. 2. Hourly vertical profiles of horizontal wind speed from HRD conical scans showing evening development of the LLJ near Lamar, CO, on 15 Sep 2003. Wind speed (m s−1) on horizontal axis, and height (m) on vertical axis. Profiles are color coded by time (UTC), which is 7 h ahead of local (mountain) standard time, so that 0100 UTC about sunset and 0700 UTC is midnight. Vertical resolution is 5 m. Turbine-rotor layer is indicated by horizontal dotted lines. (Figure courtesy of the American Meteorological Society.) Banta et al. 2013

One of the biggest challenges for producing accurate projections of wind resourcesis the assumptions made with the vertical profile with height in the lowest layer ofthe atmosphere; depends on the local terrain features and land-surface environment.

21

This is an example of a localized terrain effect, with the wind flow accelerating through Willoughby Gap; these nuances are impossible to know without collecting data.

22

Burlington

Newport

Lyndonville

Island Pond

Mt. Washington

0 10 20 30 40 50 60 70 80 90 100

29.3

17.4

13.6

9.7

91.2

Percentage of Time Wind Speed Greater Than or Equal to 10 knots (11.4 MPH) (Data from 2012)

Percent (%)

23

Climate Change and Local Wind Resources

24

Cold Season Jet Stream Climatology

25

Barnes and Polvani, 2013

Literature supports a shift of the midlatitude jet stream north, in this papershowing the largest migration of the Atlantic jet in Fall and least in Winter.

26

19701972

19741976

19781980

19821984

19861988

19901992

19941996

19982000

20022004

20062008

201025.0

30.0

35.0

40.0

45.0

50.0

Mt. Washington, NH Average Annual Wind Speed (1970-2011)W

ind

Spee

d (M

PH)

Average: 39.5 MPHData courtesy Mt. Washington Observatory and Plymouth State University

27

19701971

19721973

19741975

19761977

19781979

19801981

19821983

19841985

19861987

19881989

19901991

19921993

19941995

19961997

19981999

20002001

20022003

20042005

20062007

20082009

20102011

-15.0%

-10.0%

-5.0%

0.0%

5.0%

10.0%

15.0%

-6.3%

-3.1%-2.6%-2.9%

2.7%

-3.2%

5.6%

-0.2%

-2.3%

-12.4%

3.9%

0.0%

6.6%

0.4%

-2.4%

9.2%

6.2%

4.3%

11.8%

5.0%

9.3%

5.3%

-3.4%-2.5%

9.8%

-3.6%

-2.0%

12.1%

-10.0%-9.6%

-12.3%-13.0%

1.9%

-0.7%-0.1%

-9.5%

4.3%

10.6%

-1.4%

-3.4%-4.5%

2.1%

Mt. Washingon Yearly Wind Speed Variability (1970-2011)

Average: 5%

Data courtesy Mt. Washington Observatory and Plymouth State University

28

Climate Change and Wind Resources

• Observations: – We don’t know the answer, developing field, Global

Climate Models need to be downscaled for this application

– There will probably be some seasonal shift to wind resources

– Year-to-year variability is larger than the long-term climate signal

– There do not appear to be any long-term changes atop Mt. Washington

29

References• Banta, Robert M., Yelena L. Pichugina, Neil D. Kelley, R. Michael Hardesty, W. Alan Brewer, 2013: Wind

Energy Meteorology: Insight into Wind Properties in the Turbine-Rotor Layer of the Atmosphere from High-Resolution Doppler Lidar. Bull. Amer. Meteor. Soc., 94, 883–902.

• Barnes, Elizabeth A. and Lorenzo Polvani, 2013: Response of the Midlatitude Jets, and of Their Variability, to Increased Greenhouse Gases in the CMIP5 Models. J. Climate, 26, 7117-7135.

• Carrera, Marco L., John R. Gyakum, Charles A. Lin, 2009: Observational Study of Wind Channeling within the St. Lawrence River Valley. J. Appl. Meteor. Climatol., 48, 2341–2361.

• DOE, 2013: Energy Sector Vulnerabilities to Climate Change and Extreme Weather: http://energy.gov/sites/prod/files/2013/07/f2/20130716-Energy%20Sector%20Vulnerabilities%20Report.pdf

• IPCC, 2012: Renewable Energy Sources and Climate Change Mitigation: Special Report of the IPCC. Cambridge University Press. 1088 p. Available: www.ipcc.ch/pdf/special-reports/srren/SRREN_Full_Report.pdf

• NOAA ESRL Web Plotting Analysis Tools: http://www.esrl.noaa.gov/psd/cgi-bin/data/composites/printpage.pl