https://www.sciencedirect.com/search?qs=Solar%20Radiation%20Data%20For%20North%20Africa&show=25&sortBy=relevance

Either the NASA meteorological website, or the TMY data are recommended. A comparison between these types of data is available in the following article,

https://www.researchgate.net/publication/273178841_Photovoltaics_energy_Improved_modeling_and_analysis_of_the_levelized_cost_of_energy_LCOE_and_grid_parity_-_Egypt_case_study

Hello,

For accurate measurement you can use Pyranometer. But if it isn't possible, just use NASA's website and enter the location Latitude by searching from google in the following site "https://eosweb.larc.nasa.gov/cgi-bin/sse/grid"

I hope this may help.

You have solar radiation data in: Photovoltaic Geographical Information System. It's easy to use and has a large amount of free access data from Africa, Asia and Europe.

http://re.jrc.ec.europa.eu/pvgis/apps4/pvest.php?lang=es&map=africa

You have the information in several languages: English, French, German, Spanish

Easy! My company Solcast offers FREE access to solar radiation data for researchers like yourself, read more at:

https://articles.solcast.com.au/solar-data-api/free-access-to-solar-irradiance-data-for-non-commercial-research-use

And

http://solcast.com.au

You'll be able to find data for your location, plus anywhere else in the world.

Thanks Dr. Nick

Are these data measured?

Yasser Fathi Nassar - no they are not, but should be considered a good option if you have difficulty finding measured data (which is often the case).