A decade ago, it took the world a year to add a gigawatt of solar power capacity - now it only takes a day.
Earlier this month, Our World in Data released this highly gratifying graph showing that in 2004, it took about a year for the world to add one gigawatt of solar power capacity. Less than a decade later, in 2023, the same amount was added every single day on average.
One gigawatt of solar is enough to power around 200,000 homes in the U.S. - meaning the world’s capacity for powering homes with renewable energy has been expanding at a phenomenal rate - and will continue to do so. Much of this growth is happening in China, which in 2023 accounted for about 43 percent of installed solar energy capacity globally.
The fundamental driver of this change is that renewable energy technologies follow learning curves, which means that with each doubling of the cumulative installed capacity their price declines by the same fraction. The price of electricity from fossil fuel sources however does not follow learning curves so that we should expect that the price difference between expensive fossil fuels and cheap renewables will become even larger in the future.
What about prices today? Well, prices for solar panels have dropped by about 95 percent since 2001 from $6.21 per watt to $0.31.