We all agree that the world needs to become carbon neutral. The only open questions are how, when, and who’s going to pay for it.
To get a grip on the scale of the challenge, I will do what any well-meaning amateur would: some back-of-the-envelope math. It’s wrong, obviously. You should trust the scientists. But I’m doing it anyway. Sue me.
And because I needed a starting point—and because I’m French—I focused on France.
TL;DR – Good Luck France
| Option | Units Needed | Land Required | Notes |
|---|---|---|---|
| Nuclear | ~275 reactors (218 new) | Existing plants + 87 sites | 5–7 years to build (in China) |
| Wind | ~301,000 turbines | ~50,598 km² (9.17% of France) | Variable renewable energy |
| Solar | ~10.3 billion m² panels | ~10,300 km² (1.9% of France) | Variable renewable energy |
Let’s do it
France’s total final energy consumption in 2023—including transport, heating, and industry—was around 1,549 terawatt-hours (TWh).
Source: Ministère de la Transition Écologique – Chiffres Clés de l’Énergie 2024
Let’s Go Full Nuclear
In 2023, France’s 57 nuclear reactors produced 320 TWh across 18 plant sites.
Source: World Nuclear Association – France
That means:
- One reactor produces about 5.6 TWh per year
- One plant site handles around 17.8 TWh per year
To cover France’s total demand:
- We’d need ~275 reactors
- Or ~87 plant sites
Since 57 reactors already exist, that’s 218 new ones. For reference, China can build a plant in 5–7 years. Your mileage may vary.
Blowing in the Wind
Now let’s assume perfect energy storage. No losses, no downtime. Just pure, steady magic. Because, no production when there is no wind.
France had about 9,500 wind turbines in 2023, producing 48.9 TWh.
Source: RTE Production Électrique 2023
So:
- One turbine averages 5.15 GWh per year
- To meet the 1,549 TWh demand: we’d need ~301,000 turbines
Turbines must be spaced 410 meters apart.
Source: Renewables First
At that spacing:
- Each turbine claims about 168,100 square meters
- 301,000 turbines would require ~50,598 km²
- That’s about 9.17% of France’s land
Of course, you can still plant wheat or play football under them.
Lazy Sunny Afternoon
For solar as well, let’s assume perfect energy storage. No energy production during the night. In 2024, France’s solar panels produced around 23 TWh.
Source: RTE – Solar Generation
Average yield in France is about 150 kilowatt-hours per square meter annually.
Source: PVGIS – Limoges
So to hit 1,549 TWh:
- We’d need around 10.3 billion square meters of solar panels
- That’s roughly 10,300 km² — about 1.9% of France
I think this might be much more because I did not take into account spacing of the solar panels.
This was a fun little exercise I’ve been meaning to do for a while. If I botched the math or used the wrong numbers, feel free to yell at me on Mastodon.
Want to go deeper?