The Uncertain Future of Nuclear Power

"One leading theory is that his stomach blocked the view of the control panel" I wonder if this is why the creators of the Simpsons decided Homer Simpson should be a safety inspector at a nuclear power plant.

The most frustrating part about the Three Mile Island accident is that the automatic systems would have prevented the meltdown, but the operators suppressed those actions due to their misinterpretation of the conflicting information.

Pretty much everyone who talks about Onkalo, the Finnish nuclear waste storage, misses one VERY crucial factor: It is built in a Craton. A craton is part of earths crust and is always going to be the oldest due to the way it is formed. Craton is twice as thick and has long tendrils that extend deep in the magma. They are not really like plates, but more like islands floating in a sea of rock.. They are lighter in density so they float on top of everything. What this means is that they are extremely stable formations, with no volcanic activity, no earthquakes. They are solid lumps of gneiss and granite, the bedrock is 4 billion years old and may even be here when the sun devours the Earth. If there is anything permanent in this ball of ours, it is the cratons. Other crust formations may push them around, for ex Baltic Shield was one located near where South Africa is now, just pushed up north but has remained intact. This is why parts of Finland and Sweden can build safe storages in the bedrock, they sit partially on top of the Baltic Shield. You drill a hole in it and it will be there, millions of years from now without any additional maintenance. Other cratons in the world are for ex north-east Canada and south-west Australia. Those locations are perfect for storing stuff for hundreds of thousands of years. They are also excellent for any kind of caves and storage space, Finland uses it for national defence, for ex there is a bomb proof second city under Helsinki that can withstand a nuclear blast that can house 600 000 people. Finland and Sweden dominate underground excavation equipment market, not really a surprise after knowing what the bedrock is like here.. We could build Moria here, several times over.

The most frustrating part of the fukushima disaster isnt just that the four reactors were built on a fault line on the pacific side (most at risk of tsunami) of japan, its that the reactor was built from a design meamt for the midwest united states where tornados are common, and thus generators are safest underground beneath the building. Not safe for a place that is prone to earthquakes and at risk of flooding from anticipated tsunamis. Managerial and architectural neglegence is what ultimately caused the fukushima disaster, that's what made it so vulnerable. it was working class heroes that responded to it, and they will probably never be adequately recognized

Molten salt has fundamental challenges that haven't been addressed and are generally glossed over in videos like this, and it goes far beyond "not ready for commercialization". With existing reactors, all of the nasty fission products are hermetically contained by the zircalloy cladding on the solid fuel rods. This lets us manage the waste safely and economically. We park it in a pool of water for a few months while the short-lived isotopes decay away, then the fuel rods get cool enough for dry cask storage, where they can sit for 100+ years without bothering anyone (you can walk next to a dry cask w/o any risk). Dry casks are big concrete things that don't need any electricity or maintenance other than basic monitoring and security (is it still there? Is it cracked? Is anyone actively drilling into it? OK, great, back to sleep), which is why many nuclear plants decide keep all of the waste they generate during their 60 year operational life, at ... an on-site parking lot inside their existing security perimeter (it's a tiny volume of material). People obsess about 30,000 year storage, but the reality is that the vast majority of the radioactivity is released within the first 100 years and the danger beyond that point is far less significant, and thus, easier to manage. Fuel reprocessing gets easier when all but two of the radioactive elements are gone (Sr and Cs). If global civilization is destroyed to the point where we can't monitor a handful of unpowered dry casks, then the hunter gatherers living in the detritus of civilization will have bigger problems to deal with than a few mildly radioactive fuel rods that didn't get their UN-sponsored pictograph explaining that radiation=bad. For example 9 degC of climate change is a far bigger burden to future hunter-gatherer tribes than anything we could do with our nuclear waste. Now imagine that the fuel is a molten salt. Fission products contain dozens of different radioactive elements. Some are solids that precipitate out of the salt. Others are solids that dissolve in the salt. Others are liquids. Others are gasses the bubble out of the salt and must be captured. In particular, Xenon-131 is a dangerous short-lived gaseous isotope that's tricky to capture. So we just "scrub the fission products from the fuel salt"... um, ok. That "scrubbing" is a chemical reprocessing plant, and the only examples we have of doing this are massive sprawling facilities that cost many billions of dollars and are THE source of the vast majority of the difficult to handle nuclear waste problems. Hanford. Chelyabinsk. It's an inherently difficult problem. Every chemical reagent becomes contaminated with radioactive isotopes, generating large volumes of low-level waste, much of it in liquid form. Every piece of equipment becomes low-level waste. Most of the processes have to be operated robotically. It's then difficult / expensive to maintain the now-radioactive machinery or to fix problems. Oh, and there's a near 100% overlap with the technology needed to extract weapons grade Plutonium for a bomb program, so there's inherent proliferation concerns with commercializing any form of "fuel scrubbing". It's also illegal in the US, so you have to get the law changed. None of this is easy, technically or politically, yet it gets hand-waived down to a single "scrub the fission products" sentence while the trivial challenges with solid fuel rods are portrayed some kind of disadvantage. Update: while my post addresses the molten fuel salt designs referenced in the video, several of the comments underneath have pointed out that there are interesting solid fuel designs that use molten salt as a coolant, such as Berkley's PB-FHR project (design studies; not hardware). I find these designs quite intriguing, especially their claims of fully passive decay heat management, which addresses what I view as the hard problem of nuclear safety. From digging through Berkeley's PDFs, one of their biggest remaining challenges seems to be that their coolant salt breeds Tritium when exposed to neutron radiation, which it absolutely will be inside a reactor core. I skimmed extensive discussions on methods to sequester the resulting tritium before it can work its way into structural metals and make them both embrittled and radioactive. That's not great, but it seems much closer to becoming a practical reality than molten fuel salt designs. And it attacks an important problem. There's a company named Kairos working on a commercial design, but they have almost no public info that I can find. Best of luck to them.

Dry storage casks are not dangerous. One of the most famous examples of just how safe those things are had the testers ram it with an entire TRAIN, and it barely budged. They then proceeded to drop that same cask from several hundred feet, and set it so that it hit the ground with the corner(aka the point of most likely failure), and nothing happened to it(or it was drop test first followed by train ramming, not sure, but point still stands). Those things are literally the safest things humanity has ever designed.

The above ground containers that hold nuclear waste are extremely safe to the point where the people who designed it can be seen hugging the containers full of the stuff because they are so confidant in its design

Correction: Liquid water is NOT a great conductor of heat. It is a good store of calorific enerygy with lesser change in temperature, hence can be used to move heat energy from one place to otehr safely

2:10 His stomach blocked the view. This is the most American way of causing a nuclear disaster.

Its a slight shame you didn't mention the UK's funding of Rolls Royce's SMR project , a government funded SMR project like you suggested. Rolls Royce also already have large factories and a huge employee base, plus they're a trusted name for customers.

My wife's grandfather was the vp of electrical generation at met ed when tmi happened. I inherited all of his engineering related items he saved throughout his career and by far the coolest thing is his documentation on the melt down. The transcripts from his debrief with the NRC are brutal. What has always confused me is the mystery aspect of the event. The maintenance supervisor knew exactly what happened and what had unfortunately already resulted from the loss of feed water.I can tell you this. He was literally the first point of contact and it took him roughly 40 minutes to arrive on site and the first note he took was the wind heading and mph....

Fukushima also had a massive human element to it; greed. The company in charge of the plant was warned by multiple agencies, including their own engineers, that massive improvements to the plant were needed to make it safe in case it was hit by a tsunami of that level. All of those warnings were ignored. At other, more up to date plants in the disaster zone of the tsunami, there wasn't the devastation that you saw at Fukushima. In fact, some housed people left homeless from the tidal wave.

4:50 I would like Real Engineering to do a video on these "dangerous interum storage facilities" like dry cask storage. You may find it to be more nuanced than simply calling them dangerous.

What hasn't been mentioned in this video is... One safety failure at 3 Mile Island was the control room lights were only connected to the switches and not the actual valves in the pipework. So when an Operator selected a switch to close a vent valve, the control panel showed it as "Closed" but the valve failed to move. Therefore the Operators had no way of knowing the real position of the vent valves. What should have been the design, was the control panel lights should be connected directly to the valves and machinery that its display represents

Near my hometown in Ontario CA, a nuclear power station called Bruce Power recently announced that their third power station will be modular. They already operate 8 CANDU reactors undergoing life extension modifications. I think this site would be an interesting case study for you to check out.

Cheap prices of renewable energy sources are always deceptive if storage cost to deal with intermittency are not taken into account

The three mile island incident blows my mind. I spent a decade working at a tier 3 data center owned by a huge financial institution. The possibility of downtime was so terrifying to them due to the millions of dollars per minute they'd lose that our SOPs were basically idiot proof and it was the senior engineer's job to make sure every step was followed in the correct order. Whoever was in charge of the SOP during a given power transfer or maintenance operation would 100% lose their job if their was a fuckup. I can't understand how a nuclear power plant would be any less meticulous.

I work in the nuclear industry in Canada. I can tell you that money is the reason that many of these issues arise. The fight between production/supervision and quality control means that some things get rushed or blind-eyed to make "everybody happy". The client only pays X, and any hiccups in time or production schedule mean more cost to the customer. You need to make the customer happy because if they took their contracts to your competition after the current contract completes, a lot of people would be out of work. It's absolutely not how the nuclear industry should function.

no matter how advanced the reactor is it's still very impressive to me that we keep going back to steam turbines

I would recommend that the viewers of Johnny Harris' nuclear video rather watch the videos on this channel. this is real engineering and not journalism.