How a Nuclear Reactor is Designed and Built

If you have ever wondered how a nuclear reactor is built and designed, check out the video below.  It is a graphical overview of the European (or Evolutionary depending on who you ask) Pressurized Reactor, a Generation III+ nuclear reactor design by Areva, the French multinational.  This thing is truly a fortress: a twenty foot thick concrete slab to support all plant buildings, emergency backup diesel generators on opposite sides of the facility so a terrorist attack from the sky would only take out half of them, a three-foot thick concrete containment structure built around another three-foot thick concrete containment structure to protect the public from any radiological accident while also protecting the reactor from a direct strike from a jumbo jet, and a core catcher, designed to catch and cool the melted corium in case all other safety systems fail. That is not to mention the design of the power generation portion of the plant itself, with the reactor pressure vessel and its four massive steam generators pumping out around 4,500 megawatts of heat and 1600 megawatts of electricity.

How a Nuclear Reactor is Designed

There are currently four of these reactors under construction right now, two in Europe and two in China, with a handful of others in the planning stages in the United States, Europe, and India.  This first video is a three dimensional overview of the EPR reactor design, from construction to systems testing, fuel loading, and power operation.  At 1:55 in you can see the reactor pressure vessel get installed, and at about two minutes in you can see the four massive steam generators being installed around it.


So how well did this plan work out in real life?  Well not on schedule or on budget, that much I know.  The first of four EPR projects under construction, Olkiluoto 3 in Finland, broke ground in August 2005 and is still not complete.  The original plan was a four-year construction period with commercial operation starting in 2009, but due to repeated delays, it is not scheduled to start producing electricity until 2015 now.  Much of the delay is due to this being the first plant of this design, so some hurdles are to be expected, but a six year delay on a four year project is, well, disappointing.  Add onto that cost overruns that have more than doubled the original cost of the plant to over $10 billion, and you can see why people are skeptical about new nuclear power.  This is not to say that this unit won't still be very profitable over their sixty year lifespan as construction is a huge chunk of a nuclear power plant's cost, but it is still difficult for the company who has to deal with these cost overruns now.  A very similar situation is happening at the second EPR under construction in France.

How a Nuclear Reactor is Built

Interestingly, the third and fourth European Pressurized Reactors being built in China are on schedule and on budget. They first Chinese unit started construction four years after the very first EPR started construction and after that same unit was originally scheduled to become operational, and yet it is currently scheduled to be the first EPR to become commercially operational.  Similarly, the second Chinese unit is also on schedule and on budget, with the entire cost for both nuclear units costing less than one in Europe.  It just goes to show you what bureaucracy can do for you.

The video below is similar to the first one, but actually follows the construction of each of the EPRs being built, along with a timeline to show how fast progress was being made.  Notice that the two Chinese units very quickly catch up to the Finnish and French units.  Since this video is not captioned, I will list the big points and the time they show up in the video for the first unit under construction.

• 0:24 - Begin pouring 20 foot think concrete base for all plant buildings
• 0:30 - Begin construction of outer and inner containment structures, each three feet thick
• 0:50 - Install polar crane that is used to move equipment during construction and maintenance
• 0:52 - Inner containment dome is installed
• 0:57 - Outer containment dome is constructed
• 1:04 - Reactor pressure vessel is installed
• 1:35 - Steam generators are installed
• 2:18 - Core plate (supports weight of fuel and allows water to flow through) and core shroud are installed
• 2:25 - Fuel support structure is installed (keeps fuel bundles in proper grid pattern

So that is nice, but what does this construction actually look like?  For that, I refer you to the video below, which is the installation of the inner containment dome on the Olkiluoto 3 unit.  You can see the yellow polar crane easily as the dome is lowered over top of everything.  I have to say, even as an engineer who understands the risks and safety systems in place during construction, I would be very uncomfortable to be the guy standing on the top of the crane as the steel dome is lowered over top of me.  This video is from 2009, so it is before the Chinese units were even started, yet now they have caught up and passed the Finnish and French units.