23 billion sounds like a lot of panels. How big is that number?
First, a sense of proportion is needed: Every day, the world uses about 90 million barrels of oil. It takes less than 9 months to use up 23 billion barrels of oil. This has been happening for decades. So we’re already in the habit of using up 23 billion of things at a regular rate.
23 billion solar panels is about 20 years installation if we keep moving at 2020 rates [1]. The rates are climbing every year.
The solar installation industry is nowhere near mature; it really only became commercially significant around 2015. If you travelled back in time and explained to oil industry people in 1910 that one day the world would need 90 million barrels a day, it would have been taken as proof that oil would never be practical.
I work in the renewables industry, mostly around solar farms. My solar farm clients typically have around 400,000-ish panels in a farm. A few of my clients have over a million. Solar farms keep getting bigger every year as we learn more about how to economically scale up their construction and operation. The Sun Cable project in north-western Australia will have about 30 million panels in a single set of solar farms.
Even if every solar farm stayed at 400,000 panels, that’s about 57,000 solar farms, scattered around the sunny parts of the world. It sounds like a lot, but for a sense of scale: there are over 150,000 used car outlets in the US alone.
If the average solar farm size grows to 2 million panels (pretty realistic), then less than 12,000 solar farms are needed.
This graphic is also helpful [2]:
There’s going to be an environmental cost with covering up a lot of land. But there are benefits too. For example: sheep like the shade and the rain protection, so merging solar and sheep farms is pretty straightforward. That’s a part of the land-use problem solved. There is a lot of other R&D happening on the topic of dual-use for solar farm sites.
The take-away point is: 23 billion is not a scary number when you work in the energy industry. It’s already in progress.
Footnotes:
[1] The rates are climbing every year, but it’s not clear where they’ll peak or start to taper off, so assuming a flat rate is a reasonable coarse approximation.
[2] Source: Archi-Ninja | The Surface Area Required to Power the World with Solar Panels
[3] Source: ACT solar farm announces new tender ..... for sheep | RenewEconomy