An Honest Comparison
The UK is betting its energy future on offshore wind. The government's target is 50 GW of offshore wind capacity by 2030. Nuclear gets lip service. The assumption — rarely examined — is that wind is cheaper, faster, and better.
Is it? Let's compare honestly, using real numbers.
Capacity Factor: The Number That Matters Most
A power station's rated capacity and its actual output are very different things.
- Offshore wind capacity factor: 35–42% (UK average)
- Onshore wind capacity factor: 25–30%
- CFF HTGR capacity factor: 90%+
A 1 GW offshore wind farm actually produces
0.35–0.42 GW on average. A 1 GW nuclear plant produces
0.9 GW+. To match 1 GW of nuclear output, you need roughly
2.3 GW of offshore wind capacity — and even then, the wind farm's output varies from zero to full depending on conditions.
Dispatchability: Who Controls When?
Wind generates when the wind blows. That's it. You cannot choose when.
- Winter evening peak demand: Wind may or may not be blowing
- Dunkelflaute (dark doldrums): Extended periods of low wind AND low sun — happens every winter in Northern Europe, typically lasting 5–15 days
- Summer oversupply: Wind often generates when demand is lowest, crashing wholesale prices
CFF's HTGR modules run 24/7, 365 days a year. The
Safe-Flex system can ramp hydrogen production down to redirect up to
50.4 GW nationally to the grid within hours — the largest dispatchable reserve in UK history.
Wind has no equivalent. When it stops, it stops.
Land and Sea: The Space Question
Offshore wind requires enormous areas:
- Each turbine needs ~1 km² of sea space (for wake effects and access)
- A 1 GW wind farm typically occupies 300–400 km² of seabed
- The UK's 50 GW target requires 15,000–20,000 km² of seabed
One CFF site produces 3.6 GWe from
55 hectares (0.55 km²) of coastal land. That's
~66 MWe per hectare — orders of magnitude more power-dense than any wind farm.
The Full Comparison
| Factor | Offshore Wind (50 GW target) | CFF Fleet (28 sites) |
|---|
| Rated capacity | 50 GW | 101.3 GWe |
| Actual average output | ~18–20 GW | ~91 GW |
| Capacity factor | 35–42% | 90%+ |
| Dispatchable? | No | Yes (Safe-Flex) |
| Hydrogen production | No | 58,016 tonnes/day |
| District heating | No | 7.8 million homes |
| Desalinated water | No | 1.4 million m³/day |
| Jobs (permanent) | ~10,000 O&M | ~500,000 |
| Operating life | 25–30 years | 200 years |
| Seabed/land required | ~15,000 km² | ~15.4 km² total |
| Works in Dunkelflaute? | No | Yes |
Cost: The Nuanced Picture
Wind advocates cite the falling cost of offshore wind: £40–50/MWh at auction. This is the "strike price" — the price the developer needs to break even.
But this doesn't include:
- Grid reinforcement: ~£50 billion to connect remote offshore sites
- Backup capacity: Gas plants or batteries for when wind stops
- Curtailment costs: Paying wind farms NOT to generate when supply exceeds demand
- Transmission losses: 5–10% over long subsea cables
- Decommissioning: Every 25–30 years, the entire fleet must be replaced
When you account for system costs, offshore wind's true cost is significantly higher than the headline strike price suggests.
CFF's cost is the site build (£15 billion FOAK for Site 1, declining with fleet learning). After that, the fuel cost is negligible (uranium is cheap and energy-dense), and the site operates for 200 years.
The Real Answer: Both — But CFF Is the Backbone
This isn't about banning wind turbines. Renewables have a role. But they cannot provide:
- Baseload power 24/7
- Industrial-scale hydrogen
- District heating
- Desalinated water
- Grid stability during Dunkelflaute
The UK needs a firm foundation of dispatchable, zero-carbon power. CFF provides that. Wind supplements it. Getting this hierarchy right is the difference between energy security and energy vulnerability.
See the full energy strategy →
Carbon Free Future is an independent proposal by DJ Waugh, a retired engineer from the North East of England.