"Lors de leur audition précitée, les représentants du BRGM ont indiqué que pour remplacer un réacteur nucléaire de 1 GW fonctionnant avec un facteur de charge de 75 %, il faudrait recouvrir 5200hectares de panneaux photovoltaïques, soit la moitié de la surface de Paris."

Replacing a 1GW nuclear reactor (a power plan can have 2, 3 or 4) with a capacity factor of 75% will need 5200h of solar panels, half of Paris surface.

This doesn't also solve the transport and storage issues to handle the intermittence.

After that you simply have to do the maths. Knowing that solar panels are loosing efficiency over time and needs to be replaced after 20 years. Nuclear power plants are currently holding after 70 years.