By the end of last year, the Scottish Borders was the region with the third highest number of solar installations.
Statistics released by WWF Scotland and the Solar Trade Association show that the region 2,595 solar installations.
That is an increase of just over 41% on the same figure at the end of 2014.
Only Aberdeenshire and Fife have more installations than the Borders.
The release of the figures was accompanied by a call from WWF Scotland and the Solar Trade Association Scotland for the Scottish Government to encourage further development of solar power.
Across the country as a whole, the total installed capacity of solar photo-voltaic (PV) systems in Scotland reached 179 Megawatts (MW) in 2015 – a rise of 28% since 2014.
The two organisations said that the installations would help to prevent thousands of tonnes of climate-damaging carbon dioxide from being emitted every year.
Welcoming the data, WWF Scotland director Lang Banks said: “Despite the challenges facing the industry, it’s fantastic to see so many homes and businesses embracing solar power.
“Although the total installed solar capacity is small when compared to wind energy, we should remember that collectively these solar panels are helping to prevent thousands of tonnes of climate-damaging emissions being emitted every year.
“Following the recent conclusion UN climate talks in Paris, alongside energy saving measures, we’re going to have to see an even greater uptake of solar and other renewable technologies here and globally.
“We therefore call upon the Scottish Government to do all that it can to help ensure Scotland switches on to the full potential of solar power.”