The construction of the World's first grid scale nuclear power station - Calder Hall in North East England - was commenced by Taylor Woodrow Construction in 1953 and was officially opened on 17 October 1956, using 1950s engineering and construction techniques..

Originally designed for a life of 20 years from respectively 1956-1959, the plant was after 40 years until July 1996 granted an operation licence for a further ten years.

The station was closed on 31 March 2003, the first reactor having been in use for nearly 47 years.

Seems to me we have gone backwards.

Expand full comment

Always love your work. Thanks for injecting empirical reality into what is too often a political discussion.

Expand full comment
Apr 3, 2023·edited Apr 3, 2023

Thank you for this insightful post. A minor mistake: the UK has not turned its back on big reactors as two more EPRs are in the pipeline at Sizewell.

Expand full comment

Hi. I've recently analysed the reactors built in Europe in the last 25 years, and all of them have issues of cost overruns and delays.

Three "outliers" : Flamanville, Olkiluoto 3 (which you haven't mentioned, about to come online, and having destroyed the contractor AREVA on the process), and Hinckley Point C.

Also, six other reactors that went online in the last years have the same issues.

Plus there have been eight stopped projects, which don't appear in the statistics because of survivor bias.

For Europe (I haven't made the analysis anywhere else), the claims of construction in 6-8 years don't hold.

Plus, I would like to challenge the idea that nations can build them fast when they need them. I think it's more "when they are experienced". This might have been the case for France in the 80's and currently for S. Korea, but it's not the case now for any European company or country.

Here's my full analysis, also taking on the Russian participation in the constructions taking place now in Turkey and Hungary


In any case I share the comments on Prof Flyvbjerg's work

Expand full comment

Great research, very useful and well presented as always. A key point about any large development is that its very difficult to pinpoint when works commence. Often complex geotechnical or ground preparatory/infrastructure work takes place on site before or during the regulatory process and this builds into construction. A lot of 'construction' takes place off-site (e.g. pressure vessels) and delays can be due to supply chain issues with these parts.

Also, a point about modular reactors. They may be fast and cheap to build, but they can be inherently inefficient for thermal plants. There is a reason why nuclear (and coal) plants are very large - you need scale for thermal efficiency. This is one of the core reasons why nobody has made modular nuclear viable despite many decades of research.

Expand full comment

I would categorize SMR build-rate and pricing as “unknown” until one of those outfits has shipped ten operating copies of one design.

The global PV business, even accounting for low capacity factor, is adding the equivalent of about 13 BWRX-300’s ... each ... month.

Expand full comment

Interesting! I didn't know it takes that long. No wonder, retrofitting current plants for better waste disposal is always an issue. I think that is more concerning at the moment. Until we have a clear plan to sort out the nuclear waste, there will forever be a debate in the EU about how green the Nuclear plant is. Here is my article about it: https://www.drgreeneconomy.com/p/green-gas-and-nuclear-could-divide

Expand full comment
Apr 3, 2023·edited Apr 3, 2023

Other sources say Vogtle 3/4 began construction in 2009. Could you address this because obviously it discredits your analysis if your data is inaccurate. If your point is the site began construction in 2009 but the reactors only in 2013 isn’t that misleading? If it takes 4 years to even be ready to commence reactor construction that matters.

The $30b ish cost of Vogtle 3/4 is also relevant, as is £33b for Hinckley C. Cost matters just as much if not more than money.



Expand full comment

Fantastically useful post. Thank you!

Expand full comment

Thanks for this article. It's nice to see some numerical analysis in the presence of so much political noise.

I'm afraid there's a "But" though.

In your graphs of construction times, you arrange the data always using the date when construction started. This means that for any plant that started build in the 2010s, the longest construction time it could possibly have is 13 years to end in 2023. For a plant started in 2019, it could not be included if its build was longer than 4 years.

Arranging the data like this distorts some of the graphs. In particular, if you were to arrange the green blocks of average construction times by decade using the date the plants entered commercial service rather than the build start date you would see a significant recent trend towards slower builds that I believe your presentation has disguised - especially as regards EU & US builds.

Expand full comment

Thank you for this. I have used and credited your work on build times in my latest article on how to reduce the costs of nuclear power.


Expand full comment

Eye opener - thanks! Definitely linking to this in my next Weekly Climate newsletter 🙏.

Only thing I would love to see is how it stacks up against the same generation capacity for renewable sources (wind, solar, hydro etc). Do you have those numbers?

I guess that’s the relevant comparison to make when people are saying “nuclear is too slow”. 6.5 years is still a long time if you can build the same capacity with wind and solar in 1 year (I have no idea if you can do that just picked a random number).

Expand full comment

Can u tell me what the embedded carbon footprint is of a reactor when construction is completed?

Expand full comment

This is just one of many studies that have been published over recent years and the conclusions share many commonalities. However, construction times haven't improved as a result of those findings either because the planers ignore them, unable to translate the findings into solutions, or the findings aren't relevant to the problem. One thing that these studies haven't considered is the volume of individuals involved in the project which can be a source of miscommunication, conflict, and contradiction.

Expand full comment

Love this. Construction Physics has a great 3 part nuclear reactor series as well.


Highly recommended as additional reading.

Expand full comment