Line graph: Solar installations and cost

The line graph shows how the cost of installing solar panels and the number of installations changed in one country between 2008 and 2022, with both measures indexed to 100 in 2008.

Overall, installation costs fell steadily while the number of installations grew enormously, which suggests that cheaper panels encouraged people to buy them.

The cost index declined most quickly in the early years, falling from 100 in 2008 to 82 in 2010 and 55 in 2013. The rate of decline then slowed, with the index reaching 38 in 2016 and 28 in 2019, and it finished at 22 in 2022, less than a quarter of the starting level.

The number of installations moved in the opposite direction. It rose from 100 to 160 in 2010 and then grew far more strongly, to 420 in 2013 and 900 in 2016. The upward trend continued, reaching 1,500 in 2019 and 2,300 in 2022, which means that installations were 23 times higher than in 2008, while costs were less than a quarter of their original level.