SRB data, include monthly average data products, are available from the ASDC's website: https://asdc.larc.nasa.gov/project/SRB
Also, the Prediction of Worldwide Energy Resource:(POWER) website may be of interest for your research in data for photovoltaics.
To access the data go to https://power.larc.nasa.gov/data-access-viewer/ and click the “Access Data” button. In the window that is now visible select
1. Sustainable Building as the "User Community"
2. Click the Climatology button
3. Enter the latitude and longitude
4. Note that if Climatology is selected in Section 2, there is not need to enter a time period in section 4 since by default monthly values are currently averaged over the climatological time period July 1983 – June 2005.
5. In Section 5, Select Output File Format
6. To download the parameters (a) double click the “DOE/ASHRAE… “ folder and click on CDD, HDD and temperature at 2 meters, (b) double click the “Meteorology (Moisture and Other)” folder and click Relative Humidity at 2 meters and Surface Pressure, (c) Double click the “Meteorology (Temperature)” folder and click Earth Skin Temperature, (d) Double click the “Meteorology (Wind)” folder and click Wind speed at 10 Meters, and (e) Double click the “Solar Irradiance…” folder and click the All Sky Insolation Incident on a Horizontal Surface.
7. Click Submit. The resulting window will offer the option of plotting the climatologically averaged monthly time series for each parameter selected in step 6 and clicking the button under the “Output Files” will download the parameters in the file format selected in step 6.
Additionally, you may be interested in these websites:
RETScreen: https://www.nrcan.gc.ca/maps-tools-publ ... creen/7465