“Urgent” nuclear power? This is how long it takes to build a reactor

Yesterday, Eskom CEO Brian Molefe said that South Africa needs to add nuclear power to its electricity generating capacity “urgently”, but the problem is that a nuclear plant isn’t something that came be planned, constructed and made operational in a short space of time.

“We do not think that it is possible to continue with an energy mix that excludes nuclear. It is feasible to fund and operate further nuclear plants in South Africa and, in fact, it is urgent we do so,” Molefe told Parliament’s Public Enterprises Committee yesterday.

How long does it take to build a nuclear power plant, though?

Across the world, there are just over 438 nuclear reactors and around 149 nuclear power plants. Constructing these behemoths is no small feat, and we have crunched the numbers to determine the average time that it takes to construct a nuclear reactor. Not including the 99 stations in the US (because they report stats differently), this is where they’re located.

Number of reactors

Number of reactors per country

While various projects across the globe were a stop-start affair, the average time in construction for a nuclear reactor is 8.2 years. South Africa’s own Koeberg power station was close to pushing the ten-year mark for construction, as Unit 1 took 8.1 years to complete, and Unit 2 was just under nine-and-a-half years.

Construction time

The blue dots represent when a reactor was constructed according to the bottom time line versus the amount of time in years it took to be completed. The line is the rising average build time.

What’s interesting is that average build times are getting longer. In the last decade, for example, only China and South Korea have managed to build a nuclear power station in less than five years.

The other thing to note, of course, is that the while construction delays are almost inevitable for nuclear plants, cost overruns are the norm too (World Nuclear Industry Status Report 2015).

It also needs to be noted, that in reference to the chart above, Argentina’s Atucha II (the second upper-most dot) was mothballed between 1994 and 2007; while Iran’s Bushehr Number 1 (upper-most dot) halted construction in 1979 after the Islamic revolution of the country. Only after 1995 was a contract signed to finish construction in 2011.


The long times where construction was halted on those two stations would skew the average construction time a bit.

The data for the charts were collated from the International Atomic Energy Agency and the Nuclear Energy Institute, via Wikipedia.

[Image – CC by 3.0/Pipodesign Philipp P Egli]

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