Under the French system of Advanced Renewable Tariffs, solar PV projects are limited to no more than 12 MW. See the official documents for a description. Projects cannot be located any closer to each other than 0.5 km to prevent gaming the system. This restriction may be revisited in Grenelle 2 in the summer of 2009.
When the program was launched in 2001, wind was also limited to no more than 12 MW per project. This restriction was lifted in the 2006 revisions for wind projects in zone de développement de l’éolien.
Why 12 MW is the limit has more to do with French post-war history and the French labor movement than any particular technical reason.
