Wind energy assessment for Nevada: Observations and modelingObservations and modeling

D. Koracin, R. Reinhardt, and M. Liddle

Desert Research Institute, Reno, Nevada

161st Nortwest Regional Meeting (June 25-28, 2006)

2

How many homes can oneHow many homes can one megawatt of wind serve?megawatt of wind serve?1 MW ~ 1,000 homes100 MW wind farm ~ 30,000 homes

30% capacity factor30% capacity factor1,000 MW coal plant ~ 750,000 homes

75% capacity factor

3

DRI’s Wind Energy ResearchObjectiveTo improve wind power density maps for Nevada.Wind observations (Remote Automated Weather Stations (RAWS), 50m- meteorological towers, and an acoustic sounder) /Western Regional Climate Center/sounder). /Western Regional Climate Center/.Modeling winds and turbulence on mesoscale domains (Cycles: annual, monthly, seasonal, diurnal; Heights: 10m, 50m, and 90m; Use data assimilation to improve wind predictions; Provide probability density functions to correct model uncertainties or/and errors) /DRI’s Atmosphericmodel uncertainties or/and errors). /DRI s Atmospheric and Dispersion Modeling Program/.Use mesoscale model results (horizontal resolution of 2-3 km) as input to an adaptive grid model to simulate subgrid-scale (order of 100m or less) optimum locations for wind turbines/farms /UNLV/

4

for wind turbines/farms. /UNLV/

Main Goals & TasksDRI Observations DRI Mesoscale Modeling UNLV MicroscaleDRI ObservationsData analysisExisting stationsNew meteorology towers(50 & 100 )

DRI Mesoscale ModelingWind statisticsTurbulence statisticsWind power density mapsR i l d i

UNLV Microscale ModelingUse mesoscale modeling results to estimate

(50 m & 100+ m)Acoustic sounders

Regional domainEntire Nevada

MonthlySeasonal

optimum microlocation of the wind turbines/farms

SeasonalAnnual

NRELAdvising roleGuidance and application

DISGENLink with technology—still in progressGuidance and application still in progress

5

Why?

DRI Observations DRI Mesoscale Modeling UNLV Microscale •To provide “real” statistics of winds at existing stations•To provide new information at elevated

•Measurements—limited coverage (but needs model-evaluated results)•Planning—needs full spatial

Modeling•Physical interpolation taking into account high-resolution topographyinformation at elevated

heights (towers, sodar)•Planning—needs full spatial coverage•Measurements—limited height—interest is on first 100

resolution topography (needs to be evaluated)•Resolution on the order of 20m x 20m x 10m

m or so•Measurements-sodars—question of reliability

•To merge feasibility of access utilities

NREL DISGENLink with technology

of access, utilities, needs, and wind power density

6

Advising roleGuidance and application

Link with technology—still in progress

7

Site at northern end of Big Smoky Valley

8

Tower at theNorth end of BigSmoky ValleySmoky Valley -Installed 3Dec03

RoW authorized24 Oct 2003

9

10

11

12

Wind Energy I Model setup IGrid dimensions:D01: 120 x 95 x 39D02: 118 x 85 x 39D02: 118 x 85 x 39

Physics options used:Moisture: Mix phasepCumulus: GrellBoundary layer: MRFRadiation: Cloud

Period:1 Sep 2001-31 Aug 2002

S t f th MM5 d li d i ith h i t l

13

Setup of the MM5 modeling domains with horizontal resolutions of 9 km (D01) and 3 km (D02) and 39 full-sigma levels in vertical (first half-sigma level at 0.9985).

Model vs. observations Phase I

Full annual cycle

Comparison of modeled and measured U and Vand measured U and V wind components and wind speed for the Sepwind speed for the Sep 2001 – Aug 2002 period

Brawley Peaks, NV, 38°15’40”N 118°52’49”W38 15 40 N, 118 52 49 W

14

MM5 - Wind Power Density (W/m2) Domain 1(W/m2) – Domain 1

90m

10m

15

Annual WS frequency - D1 - 90m

16

2 Wind energy assessment study for Nevada and the Southwest:

DRI, UNLV, UNR? /DisGen/2. Wind energy assessment study for Nevada and the Southwest:

Improved estimates of wind energy potential

DRI – Site evaluation and installment of 4 meteorological towers, RAWS stations data

DRI – Mesoscale modeling (evaluation, wind density potential estimates)2003 2004 MM5 Wind power density for entire Nevada (2km resolution2003-2004 MM5 – Wind power density for entire Nevada (2km resolution –NREL suggestion); wind speed frequency; model evaluation (surface, 50m); Four Dimensional Data Assimilation; statistical parameters; Weibull distribution for measurements and model

UNLV – Refining mesoscale modeling using an adaptive grid model

G lIntegrated information (access, utility, power lines, need)

NREL – Advising role – guidance and applications

Goal: Optimum microlocation f i d f

Integrated information (access, utility, power lines, need)

17

for wind farms

DisGen – Link to technology – still in progress – possible UNR involvement

Wind Energy II 2 Domain SetupWind Energy II 2 Domain Setup

Domain 1: 10km horizontal resolution

180x180x30 grid points

Domain 2: 2km horizontal resolutionhorizontal resolution

301x401x30 grid points

Period:

1 Aug 2003 – 31

18

1 Aug 2003 31 Jul 2004

Wind speed Wind direction

19

• Comparison of U, V, and WS b t th d l dbetween the model and measurements.

•Lunig 5 meteorological tower.g g

• Height: 50m.

• Time: October 2003

Phase II Oct 2003

20

Phase II – Oct 2003

WE2-D2-Mean Wind Power Density, October 2003 at 94mOctober 2003, at 94m

21

Wind direction histograms

Brawley Peaks, NV

August 2003

Observed upper panelObserved – upper panel

Modeled – lower panel

Model reproduced well topographic channeling

22

c a e g

How to provide theoretical distributions of wind speed that are verified by measurements?

23

M. Liddle

y

Project 3 DRI, UNR (?)

3. Tall wind tower deploymentDRI – Find two tall towers (100m+) of opportunity and instrument them at three levels with standard and sonic anemometers.

DRI – Turbulence statistics (spatial and temporal variability), vertical change, long-term turbulence statistics (monthly, seasonal, annual, andchange, long term turbulence statistics (monthly, seasonal, annual, and multi-annual cycles) evaluation of turbulence schemes and elevated winds in mesoscale modeling, errors and uncertainties in the surface and elevated turbulence estimation and predictions.p

UNR – Wind turbine design, technology, and applications

NREL – Advising role – guidance and applications

UNR ?

24