Within the Energy domain, rooftop solar has the largest reduction potential in the ambitious scenario: 1,632 ktonnes CO₂-eq per year by 2030. It is followed by onshore wind with 1,385 ktonnes CO₂-eq and ground-mounted solar with 1,069 ktonnes CO₂-eq.
The strategic meaning is that roof space offers a major climate opportunity without directly using additional open land. Large-scale deployment still requires grid capacity, storage, smart demand response and fair access for households, businesses and public buildings. Rooftop solar is therefore not only a technology, but also an implementation and infrastructure task.