Complex sentence: There are some parallels between Desertec and the the 1929 Atlantropa-project which aimed to integrate Europe and Northern Africa and its electricity grid based on a giant hydro power station at Gibraltar.
Split into simpler sentences: There are some parallels between Desertec and the Atlantropa project plan in the 1920ies. Atlantropa aimed to integrate Europe and Northern Africa and its electricity grid based on a giant hydro power station at Gibraltar.