They are not poorly secured, and the material is not weaponizable. Not to mention they are not toxic sites, the waste is put into a block of metal that is completely passively cooled so it can't melt. It is buried, and it is secured. And they would generally be deployed in multi unit farms. Plus, no need to throw away the energy, especially if it's cheaper than energy from gas or coal.
That's why the reactor can use thorium! There are big benefits. But frankly all advanced reactors are cooled by natural forces so are immune to fuel overheating. The challenge is more that the consequences of accidents are way overestimated. Nobody died from radiation at Fukushima, and no one is going to. The land is not uninhabitable, some bureaucrat who sets limits non-scientifically just says it is. If people actually paid attention to data and not just assume things based on what pop culture or some bureaucrat has falsely led them to believe, people would realize the consequences of catastrophic meltdowns just aren't that bad. They shouldn't happen, but we shouldn't speculate wildly about indirect costs that are generally made up and use that as a basis for their thoughts on nuclear power. Your comments are right on in that people need to investigate nuclear. I find most people who do, find it to be a great option, while it is generally those who are opposed that didn't like it at the onset without knowing much about it and then refused to learn about it. That is why the opponents are the significant minority in the US. So your advice is good, but it's directed at the wrong crowd.
First, the reactors are consuming the fuel while deployed, but no waste is stored at the sites. It is stored centrally so there are a few centralized sites that hold the waste for a few hundred years. After which you could make things out of the material and use them around your home without issue.
The reactors cannot be deviated for nefarious purposes. And the materials are not less secure. The materials are being consumed by the reactor, and they are not dangerous as they are. In fact these reactors could destroy weapons grade material that is slated to be destroyed for fractions of the cost of programs the US is pursuing. Plus the reactors are secured when deployed. They are also buried and completely cooled by natural forces so they always stay cool. No fuel overheating.
The reactors cannot be hacked, and if a bad actor commandeered one, all they could do is turn it off safely. Even if they tried to make it hotter it would just turn off and cool down. There just isn't enough fuel in the core to do anything else.
This is one of the great challenges nuclear has to overcome on paper. Most of these costs are based on absurd standards that have consistently been proven wrong. Fukushima's cleanup would be orders of magnitude less if they didn't have to treat nearby soil as waste when its radioactive signature is far lower than the soil found at the ski slopes in CO, and even less than beach sand in Brazil. We treat low level radiation as dangerous, it really isn't. Nobody at Fukushima was exposed to high level radiation, and no one will die early due to the exposures they had. And if everybody moved back to the town and land that was evacuated, they could live their whole lives out and be fine! Why waste money on cleaning up things that are not dangerous, just lied about? Changing the standards to actually reflect science would eliminate so many of these "nebulous" costs and perceived indirect costs of nuclear power.
Also, AGR fuel needs to be condensed or reprocessed shortly after discharge. It's great in a gas reactor, not so much in a spent fuel pool. That means much of the UK's discharged fuel as been consolidated at Sellafield. But all that plutonium is a great fuel resource. Jealous of whoever gets to fuel their reactor with that goldmine.
So distribute fission and fusion, overcomes much of that. And distributed solar and wind needs backup which is usually fairly centralized. Unless you want to spend 3-5 times as much for your energy to buy batteries.
Safe = reliable = high capacity factor = revenue. Look at the INPO and NRC ratings of plant safety and economic performance. They are directly correlated. So it's in every nuclear startup's best interest to be very safe.
For over ten years the US nuclear fleet has maintained an average capacity factor of about 90%, and that is nearly 1/4 of the world's nuclear plants - http://www.nei.org/Knowledge-Center/Nuclear-Statistics/US-Nu.... It's not "some countries" it's most plants at around 90%.
There's a lot of energy in those 112 tonnes, but you really need a fast reactor to burn it. Plutonium is a lot easier to tackle in a fast reactor than a thermal reactor.
Also, UPower can use the waste without putting it through a chemical separations process. In fact you can just take the SNF grind it up, and dump it into the UPower reactor alongside the rest of the fuel. It actually makes a pretty good fuel that way.
The UPower design is waste negative so it can convert the entire planet's spent nuclear fuel and depleted uranium stockpiles into enough energy to power the globe for about 500 years. All while leaving behind a waste stream that decays to be less radioactive than the ground beneath your feet in a few hundred years. If we buried it in Paul Revere's basement when it was built, people could see it and touch it today without any exposure above background. Not to mention it is also fuel agnostic so it can run on thorium as well.
It's also important to highlight that the UPower design can consume the entire actinide vector because it uses fast neutrons. A lot of the longer lived actinides cannot be fissioned or transmuted effectively by thermal neutrons so they just build up.
We like to say we are the ultimate disposal, and can take anything, including the waste from other waste consumers.
There are neat ways to make sunlight into fuel, but it's about what form that energy takes. If it is a fuel that needs to be burned - in the case of sugars from photosynthesis - we already do this by burning wood.
I think Cosmos missed a really important lesson which is that the fuels at our disposal are all a function of time and distance. The longer a fuel source has been building, and the less distance it has to travel to be useful to us, the more valuable it may be. The sun is a result of billions of years of the shape-shifting games between mass and energy, all driven by gravity. The fusion energy produced in the sun then has to travel 93 million miles to us to be useful. The food chain harnesses this energy and accumulates it over time, and after hundreds of millions of years much of that energy has been sequestered into fossil fuels. While there is a tremendous amount of power emanating from the sun, it has to go a long way or accumulate for a long time to be useful to us. Nuclear fuel sources on the other hand bring the billions of years of nucleus building that previous generations of stars did for us to our door step. The parent stars of our sun produced heavy actinides like uranium or thorium, as well as the abundant light elements like deuterium, helium, and boron, and then scattering them across the cosmos along with leftover hydrogen in brilliant novae and supernovae. In our case, many of these elements were in the stardust that formed earth, and are here beneath our feet and above our heads.
Solar, wind, and nuclear will dominate the 22nd century, but we need both, and they do and can play well together. They just need to be treated and respected equally.
One of the main limitations is the stress it puts on the fuel.
Many advanced reactors overcome these limits, and if financially incentivized, they will definitely load follow. On top of that, the UPower reactor has a thermal transport time constant nearly 10 times that of other reactors, and its fuel is immune to the shocks that bother LWRs. In fact, the same type of fuel was used in a research reactor and would be ramped in power from 5 watts to 150 billion watts in less than 50 millionths of a second. That puts a lot of stress on fuel, yet this fuel kept its stride without breaking a sweat.
This reactor is built like a tank, and is designed to be quite resilient and flexible. It can definitely load follow to support a renewable heavy grid system. In fact it's been considered for use as a grid stabilizer at substations because of these abilities.
Hey HN I'm Jake, one of the co-founders of UPower. Some good discussion here. I've posted a few responses below, happy to answer some questions here. Thanks!
Precisely right. Traditional utilities want something with a long operating track record, something hard for new designs to do off the bat. But going where the reactor is 5x cheaper than the next best option changes that. Plus many of these places want combined heat and power, so the design needs to be flexible on the thermal end.
There are core designs for low enriched uranium loading, mixed thorium loading, and spent fuel loadings. Have to make sure a fuel design works before it's claimed to work.