Progress Towards
300 Million Solar Homes
Rooftop solar is already growing fast. The question is whether it can grow fast enough to reach hundreds of millions more people this decade.
Our working estimate is that the world will reach around 150 million rooftop solar systems sometime in 2026. Without a major acceleration, the current path is likely to reach around 225 million by 2030. The 300 Million Solar Homes goal is to help unlock a full 75 million rooftops beyond that baseline.
300 Million Solar Homes is not a forecast. It is a mobilisation target: what we believe is possible if countries and cities remove the barriers holding rooftop solar & storage back.
Rooftop solar is already growing fast. The question is whether it can grow fast enough to reach hundreds of millions more people this decade.Our working estimate is that the world will reach around 150 million rooftop solar systems sometime in 2026. Without a major acceleration, the current path is likely to reach around 225 million by 2030. The 300 Million Solar Homes goal is to help unlock a full 75 million rooftops beyond that baseline.300 Million Solar Homes is not a forecast. It is a mobilisation target: what we believe is possible if countries and cities remove the barriers holding rooftop solar & storage back.
We estimate global rooftop solar base to hit 150 million
The market is headed towards 225 million solar homes without the additional acceleration 300 Million Solar Homes is designed to support
The global target of 300 Million Solar Homes
We aim to unlock an additional 75 million rooftops above the 2030 baseline
We estimate 2 terawatt as an approximate rooftop solar capacity at 300 million systems
1 billion people stand to potentially benefit of cleaner, more affordable and more resilient electricity (300 million systems)
What counts as a rooftop system?
Capacity alone does not tell the whole story. A megawatt on one large project is different from clean power spread across homes, shops, schools and clinics. Counting rooftops keeps the focus on where people actually live and work.
We count building mounted solar systems, on homes, apartments, small businesses. schools, clinics and community infrastructure. Balcony and plug-in solar are included. Our working size range is roughly 0.3 kW to 100 kW DC.
For the purposes of this initiative, we do not count utility-scale projects, ground-mounted systems or large commercial projects above 100 kW, even when they sit behind a customer meter.
How do we estimate the global number?
There is no single global register of rooftop solar systems. We therefore start with internationally recognised distributed solar data and adjust it to estimate the share that is actually on buildings. We then account for regional differences in residential and small-business systems and average system size.
The methodology will remain public and will be updated as improved country and city data becomes available.
Read the MethodologyHow do we estimate the global number?
There is no single global register of rooftop solar systems. We
therefore start with internationally recognised distributed
solar data and adjust it to estimate the share that is actually
on buildings. We then account for regional differences in
residential and small-business systems and average system
size.
The methodology will remain public and will be updated as
improved country and city data becomes available.
300 Million Solar Homes installation tracker
We are building public data and reporting tools that will make progress towards the 300 Million Solar Homes easy to see over time. More coming soon.