Given that solar irradiation in the Sahel is very high (sometimes an annual average of more than 7 KWh/m2/day) is it possible to expect a solar panel to generate more than its power rating in these regions?

A solar panel will provide the rated power under Standard Test Conditions (1,000W/m2), Panel temperature of 25C, and no wind. There are places where at certain moments, radiation might exceed 1,000W/m2 but the temperature of the panel will also exceed 25C, creating losses that will typically make the panel not surpass its power rating.

Having said this, in places with high solar radiation, at moments when panel temperature is under 25C (eg early in a chilly morning of a clear day with high radiation), it might happen that solar panel will exceed it s power rating. Inverters will then be normally chosen having this into account in order to avoid damages due to overvoltage.