France energy profile
France — the nuclear standard-bearer, and a tidal power pioneer
57
Operating reactors — largest fleet in Europe
~65%
Of 2024 electricity from nuclear
1966
La Rance — world's first tidal power station
240 MW
La Rance capacity — world's largest tidal plant for 45 years
Built for independence, tested by corrosion
Europe's largest nuclear fleet, and the road to Flamanville
Why France went nuclear at scale:
France's nuclear buildout began in earnest in the 1970s, largely in direct response to the 1973 OPEC oil embargo — a shock that exposed how exposed France was to imported oil for electricity. The first commercial plant was commissioned in 1977, and new reactors were added on an almost-annual basis through 1999, when capacity reached roughly 61.5 GW. That build-out gave France one of the highest nuclear shares of electricity anywhere in the world, typically 70-80% depending on the year, operated almost entirely by state-owned EDF, which produces around 95% of the country's electricity across all sources.
France's nuclear buildout began in earnest in the 1970s, largely in direct response to the 1973 OPEC oil embargo — a shock that exposed how exposed France was to imported oil for electricity. The first commercial plant was commissioned in 1977, and new reactors were added on an almost-annual basis through 1999, when capacity reached roughly 61.5 GW. That build-out gave France one of the highest nuclear shares of electricity anywhere in the world, typically 70-80% depending on the year, operated almost entirely by state-owned EDF, which produces around 95% of the country's electricity across all sources.
A stress test, and a delayed flagship:
Nuclear's reliability was seriously tested starting in 2021, when EDF discovered stress-corrosion cracking affecting reactors across its fleet — serious enough that in 2022 France became a net electricity importer for the first time in over 40 years. Repairs to the most sensitive units were completed by January 2024, and nuclear output rebounded from 320 TWh (2023) to 361 TWh (2024). That same December, Flamanville Unit 3 — an EPR reactor and France's first new nuclear unit in a generation — finally connected to the grid, after delays stretching back to 2015, when manufacturing defects were discovered in its reactor pressure vessel steel. President Macron has since announced a "nuclear renaissance," targeting 14 new reactors by 2050, though independent energy analysts have questioned whether that timeline is realistic given the delays and cost overruns Flamanville itself demonstrated.
Nuclear's reliability was seriously tested starting in 2021, when EDF discovered stress-corrosion cracking affecting reactors across its fleet — serious enough that in 2022 France became a net electricity importer for the first time in over 40 years. Repairs to the most sensitive units were completed by January 2024, and nuclear output rebounded from 320 TWh (2023) to 361 TWh (2024). That same December, Flamanville Unit 3 — an EPR reactor and France's first new nuclear unit in a generation — finally connected to the grid, after delays stretching back to 2015, when manufacturing defects were discovered in its reactor pressure vessel steel. President Macron has since announced a "nuclear renaissance," targeting 14 new reactors by 2050, though independent energy analysts have questioned whether that timeline is realistic given the delays and cost overruns Flamanville itself demonstrated.
La Rance — power from the Moon, since 1966
The world's first tidal power station
How it works, and why Brittany:
La Rance, at the mouth of the Rance River in Brittany, opened in 1966 as the world's first tidal power station — decades before any other country attempted one at scale. Brittany lacks the mountains for conventional hydropower, but the Rance estuary has an unusually large tidal range, up to 13.5 metres at peak spring tides, more than enough to drive 24 turbines as water flows in and out with the tide. At 240 MW, La Rance remained the largest tidal power station in the world for 45 years, until South Korea's 254 MW Sihwa Lake plant overtook it in 2011.
La Rance, at the mouth of the Rance River in Brittany, opened in 1966 as the world's first tidal power station — decades before any other country attempted one at scale. Brittany lacks the mountains for conventional hydropower, but the Rance estuary has an unusually large tidal range, up to 13.5 metres at peak spring tides, more than enough to drive 24 turbines as water flows in and out with the tide. At 240 MW, La Rance remained the largest tidal power station in the world for 45 years, until South Korea's 254 MW Sihwa Lake plant overtook it in 2011.
The economics and the tradeoffs:
La Rance's capacity factor is only around 27% — lower than nuclear's 85-90%, similar to onshore wind — because tidal flow strength varies through the day. But tides are entirely predictable decades in advance, unlike wind or solar, which makes La Rance's output easy to schedule even if it can't run continuously. Construction costs were high, but have long since been recovered, and today's electricity cost is actually lower than nuclear power in France (1.8 cents/kWh versus roughly 2.5 cents/kWh). The barrage has reshaped the local ecosystem through progressive silting — some species like sand-eels and plaice disappeared, while others such as sea bass and cuttlefish have returned over time.
La Rance's capacity factor is only around 27% — lower than nuclear's 85-90%, similar to onshore wind — because tidal flow strength varies through the day. But tides are entirely predictable decades in advance, unlike wind or solar, which makes La Rance's output easy to schedule even if it can't run continuously. Construction costs were high, but have long since been recovered, and today's electricity cost is actually lower than nuclear power in France (1.8 cents/kWh versus roughly 2.5 cents/kWh). The barrage has reshaped the local ecosystem through progressive silting — some species like sand-eels and plaice disappeared, while others such as sea bass and cuttlefish have returned over time.
Questions
Questions about French energy
Why did France's nuclear-heavy grid suddenly become vulnerable in 2022, if nuclear is normally so reliable?
Nuclear's reputation for reliability comes from running the same proven design across many units for decades — but that consistency cuts both ways: if a problem shows up in one reactor's materials or design, it's likely to show up across the whole fleet built the same way, all around the same time. That's exactly what happened in 2021, when EDF discovered stress-corrosion cracking in pipwork at some reactors — a materials problem, not an operating error — and it had to methodically inspect and repair units across the fleet to be sure how widespread it was. Because so much of France's electricity comes from nuclear, taking multiple reactors offline simultaneously for inspection and repair had an outsized effect on total generation, at the same time European gas and power prices were spiking after Russia's invasion of Ukraine. The combination pushed France into being a net power importer in 2022 for the first time in four decades — a striking reversal for a country that normally exports large amounts of nuclear-generated electricity to its neighbours. By 2023, as repairs on the most sensitive units were completed, France was back to being a net exporter, and 2024 output recovered further as Flamanville 3 added new capacity. The episode is a useful illustration of a broader nuclear-fleet risk: concentration in one technology and vendor lineage means a shared vulnerability can affect many plants at once, in a way that's less likely across a more diversified generation mix. Source: US EIA · IEEFA · S&P Global Commodity Insights.
Provenance
Attribution and citation
- Sources
- US EIA · World Nuclear Association · IEEFA · Wikipedia (Rance Tidal Power Station) · EDF Group · S&P Global Commodity Insights · Pestel-Analysis (EDF corporate history)
- Cite as
- "France Energy Profile — Complete Reference", The Energy Codex, https://thecodex.expert/energy/countries/france/, last updated .