That is the conclusion of Oxford University researchers, based on a new forecasting model published in Research Policy.
Since the 1980s, panels to generate electricity from sunshine have got 10% cheaper each year. That is likely to continue, the study said, putting solar on course to meet 20% of global energy needs by 2027.
By contrast, even in its “high renewable” scenario, the International Energy Agency assumes solar panels will generate just 16% of electricity in 2050. Its widely cited future energy scenarios in previous years failed to predict solar’s rapid growth.
Mathematics professor Doyne Farmer, who co-wrote the paper, said the research could help to shape clean energy policy.
“Sceptics have claimed that solar PV cannot be ramped up quickly enough to play a significant role in combatting global warming,” he said.
“In a context where limited resources for technology investment constrain policy makers to focus on a few technologies… the ability to have improved forecasts and know how accurate they are should prove particularly useful.”
Farmer’s model, jointly developed with economist Francois Lafond, draws on historical data from 53 different technologies.
“We put ourselves in the past, pretended we didn’t know the future, and used a simple method to forecast the costs of the technologies,” Farmer explained.
Last week India’s coal minister Piyush Goyal said solar was now cheaper than coal in some states after the latest auction of solar capacity.
“Through transparent auctions with a ready provision of land, transmission and the like, solar tariffs have come down below thermal power cost,” he tweeted.
“We are moving rapidly towards realising the clean energy vision of Prime Minister Narendra Modi.”