4th Meeting IEA SHC Task 36 Hamburg 23-25 Oct 2007

Solar radiation forecasting with WRF model in the Iberian Peninsula

L. Martín, J. Polo, L.F.Zarzalejo, A. NavarroEnergy department CIEMAT

R. MarchanteInvestigaciones y Recursos Solares Avanzados IRSOLAV

(www.irsolav.com)

E. Lorenz, A. Sood, K. Suselj Oldenburg University, Germany

Energy and Semiconductor Research LaboratoryEnergy Meteorology Group

4th Meeting IEA SHC Task 36 Hamburg 23-25 Oct 2007 2

Outlook

1. Motivation and objectives

2. ECMWF ERA-40 validation

3. WRF validation

4. Synoptic situation: comparison of ECMWF and WRF models

5. Conclusions

EUROSUN 2008, Lisbon, October 2008EUROSUN 2008, Lisbon, October 2008

4th Meeting IEA SHC Task 36 Hamburg 23-25 Oct 2007

Motivation and objectives

Objectives

Validate ECMWF ERA-40 Global Model.

Validate Anailsys Mesoescale WRF Model

predictions with hourly resolution.

EUROSUN 2008, Lisbon, October 2008EUROSUN 2008, Lisbon, October 2008

The need to characterize and predict solar radiation as a solar resource is legislated in Spain by different Royal decrees (RD 436/2004 661/2007).

Solar thermal and photovoltaic plants operator will compete in energy stock market. There are two basic rules in the market.

4th Meeting IEA SHC Task 36 Hamburg 23-25 Oct 2007 4

ECMWF ERA-40 VALIDATION

•Data Period:1994-2004 ten years.•Daily Goblal Solar Radiation•Resolution 1º ≈ 100Km•Ground measurements from National Radiometric Network from AEMet.•CM11 pyranometer•Data filtered BSRN recomendations

EUROSUN 2008, Lisbon, October 2008EUROSUN 2008, Lisbon, October 2008

4th Meeting IEA SHC Task 36 Hamburg 23-25 Oct 2007EUROSUN 2008, Lisbon, October 2008EUROSUN 2008, Lisbon, October 2008

ECMWF ERA-40 Daily Validation

W/m

2h

W/m2h

W/m

2h

W/m2h

4th Meeting IEA SHC Task 36 Hamburg 23-25 Oct 2007EUROSUN 2008, Lisbon, October 2008EUROSUN 2008, Lisbon, October 2008

ECMWF ERA-40 Daily Validation Granada

MBD:-21.67% RMSD:27.20%

W/m

2h

W/m

2h

W/m

2h

W/m2h

W/m2h

4th Meeting IEA SHC Task 36 Hamburg 23-25 Oct 2007

ECMWF ERA-40 Daily ValidationOviedo

MBD:-7.52% RMSD:39.55%

W/m

2h

W/m

2h

W/m

2h

W/m2hW/m2h

4th Meeting IEA SHC Task 36 Hamburg 23-25 Oct 2007 8

•Reanalisys with WRF over Europe domain with 3 nesting levels.•Initial conditions GFS.•Goblal Solar Radiation•Data Period 2005:1/1/2005 – 28/2/2005•Spatial resolution 27km•Temporal resolution 1h

-20 -10 0 10 20 30 40

40

45

50

55

60

65

WRF DAILY & HOURLY VALIDATION

4th Meeting IEA SHC Task 36 Hamburg 23-25 Oct 2007EUROSUN 2008, Lisbon, October 2008EUROSUN 2008, Lisbon, October 2008 9

WRF RESULTS: HOURLY

36 37 38 39 40 41 42 43 440

10

20

30

40

50

60

70

80

90

100RMSE Hourly Solar Radiation Forecasting

% R

MSE

Latitude

36 37 38 39 40 41 42 43 44-25

-20

-15

-10

-5

0

5

10

15

20MBE Hourly Solar Radiation Forecasting

% M

BE

Latitude

Normalized MBD

Normalized RMSD

Lower to higher latitude

4th Meeting IEA SHC Task 36 Hamburg 23-25 Oct 2007EUROSUN 2008, Lisbon, October 2008EUROSUN 2008, Lisbon, October 2008 10

WRF RESULTS: DAILY

36 37 38 39 40 41 42 43 440

10

20

30

40

50

60

70

80

90RMSE Daily Solar Radiation Forecasting

% R

MSE

Latitude

36 37 38 39 40 41 42 43 44-30

-25

-20

-15

-10

-5

0

5

10

15

20MBE Daily Solar Radiation Forecasting

% M

BE

Latitude

Normalized MBD

Normalized RMSD

W/m2h

4th Meeting IEA SHC Task 36 Hamburg 23-25 Oct 2007EUROSUN 2008, Lisbon, October 2008EUROSUN 2008, Lisbon, October 2008 11

SINOPTIC SITUATION 22/2/2005

Granada

Oviedo

CI from Meteosat 12:00

ECMWF Operational Model 12:00

W/m

2W

/m2

Albedo

ECMWF Mask L/O

4th Meeting IEA SHC Task 36 Hamburg 23-25 Oct 2007

Conclusions

EUROSUN 2008, Lisbon, October 2008EUROSUN 2008, Lisbon, October 2008

ECMWF ERA-40 understimates daily solar irradiance. Errors are quite high.

Analisys errors of WRF model goes from 30-98% RMSD hourly and from 23-89% daily.

WRF fed with NCEP data doesn’t reproduce synoptic situations. Further improvement using data from ECMWF.

Cloud movement is a dynamic chaotic system. A paradigm based on deterministic (NWP) and probabilistic (Statistic).

RD 661/2007 needs hourly predictions with errors lower than 20%.

4th Meeting IEA SHC Task 36 Hamburg 23-25 Oct 2007

Thank you for your attention

EUROSUN 2008, Lisbon, October 2008EUROSUN 2008, Lisbon, October 2008