More than 50% of American and German rooftops have the technical potential to host solar PV panels, with the number going up to 80% in Australia, according to a report by research company BloombergNEF and Schneider Electric. They predict that on-site solar power is set for a boom with a total installed capacity of 2.2TW in 2050. In 2020, global installations amounted to 0.27TW.

The 2.2TW figure means approximately 167 million households and 23 million businesses would have solar panels. The authors project the leading markets will be Australia, California and China.

Policy and regulation are key to ensuring that customers benefit, say the report's authors. They recommend policies that prioritise solar panels for new buildings and promote the installation of energy storage, such as batteries.

Aerial view of solar panels installed on the roof of residential houses in Huangnan Tibetan Autonomous Prefecture, Qinghai Province of China. (Photo by Ma Mingyan/China News Service via Getty Images )

Storage can help make the business case for solar power to end users, states the report. Solar plus storage can also provide services such as grid balancing and increased resilience and helps customers shift at least part of their energy consumption to off-peak hours.