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Canadian provinces band together to develop nuclear reactor technology

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201–210 of 323 posts

Re: Canadian provinces band together to develop nuclear reactor technology

#201

Earlier quoted context omitted.

AIUI, one concern with nuclear reactors is what to do with the waste. A 'breeder reactor' is a type of nuclear reactor that makes more efficient use of uranium than 'light water reactors' and with less left-over radioactive waste. Sounds great, so why do we build anything else? Well, once you've got a breeder reactor it's a very short step to making weapons-grade plutonium. Whereas with light water reactors, this isn…

>one concern with nuclear reactors is what to do with the waste. Actually, no. The reactor designs in use generate very little waste, just spent fuel rods that have to be kept in safe storage until their radioactivity level goes down to something reasonable. That doesn't take decades, either. The big problem with nuclear waste is the waste from weapons production, and people don't differentiate just like they don't f…

I'm pretty sure I've read articles saying America doesn't currently have a permanent storage facility for nuclear waste such as spent fuel rods, and that the creation of one is politically controversial - have matters changed since I read those articles?

Re: Canadian provinces band together to develop nuclear reactor technology

#202
post #160

Earlier quoted context omitted.

Wind and solar charge batteries/pumped hydro at vastly lower prices. If you take 2c/kWh solar add 50% oversupply to cover seasonal issues you’re at 3c/kWh. Thus it’s really storage that Nuclear needs to compete with not generation. Further, as nuclear takes years to build it’s competing with future battery prices 5-55 years from now. Using conservative total system costs of say 200$ per kWh of storage every day for 1…

As wind/solar scales, it's likely to get more regulation. There will be fires in battery facilities. People in San Bernardino county will put a moratorium on large solar installations in the desert due to dust storms, etc. This kind of thing always happens, and with wind/solar it will be because they take up so much land and raw materials. Nuclear was once a wonder energy source (in 1958), but as it scaled it ran int…

Solar’s energy density is surprisingly high. To average 1GW of solar at 30% capacity factor = 3.4GW @ 220w/m^2 = 0.076% of San Bernardino county. Put all of the states electricity generation as solar in that one county and your at ~2% land area. Even that’s not going to have any effect on dust storms.

EROI is a function of price in that you need to pay for more than just energy when building something, interest payments for example. If your infrastructure costs X$ to build it must use far less than X$ worth of energy. And, if you’re building the cheapest energy source possible it must therefore have a high EROI.

Re: Canadian provinces band together to develop nuclear reactor technology

#203
post #180

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A huge number of 74 year old technologies are available for $0.75 direct from China. The fact the nuclear reactor hasn't been miniaturized to the size of a coin and included in every $15 childrens toy to power lights is in large part because of public perception and government regulation rather than real safety/health concerns - there exist plenty of typical household materials that are more dangerous than the safest…

>The fact the nuclear reactor hasn't been miniaturized to the size of a coin But it has, or at least close to: RTGs[1] weighting a couple dozen kilograms are used in space exploration and in rare cases in cold climates. Their main problem is low power density. Nuclear pacemakers[2] of just a few centimeters across used to be a thing - long lasting and reliable. Also used thermoelectric generators. Replaced by cheaper…

> 2) Critical mass:

Can be dramatically reduced with a neutron reflector [1]. Bare Sphere's [2] can be as small as 6.9cm diameter, and use of a neutron reflector could perhaps reduce that by half or more. 3.5cm is pretty small. Research is still ongoing into reflecting neutrons, and it's possible that some clever arrangement of neutron 'lenses' might allow criticality with almost no mass.[3]

[1]: https://en.wikipedia.org/wiki/Neutron_reflector

[2]: https://en.wikipedia.org/wiki/Critical_mass#Critical_mass_of...

[3]: https://www.isis.stfc.ac.uk/Pages/neutron-reflectivity---int...

Re: Canadian provinces band together to develop nuclear reactor technology

#204

Earlier quoted context omitted.

>one concern with nuclear reactors is what to do with the waste. Actually, no. The reactor designs in use generate very little waste, just spent fuel rods that have to be kept in safe storage until their radioactivity level goes down to something reasonable. That doesn't take decades, either. The big problem with nuclear waste is the waste from weapons production, and people don't differentiate just like they don't f…

I'm pretty sure I've read articles saying America doesn't currently have a permanent storage facility for nuclear waste such as spent fuel rods, and that the creation of one is politically controversial - have matters changed since I read those articles?

Mostly that for it to matter with any urgency, we'd need to actually be building new reactors. We aren't building them, so we aren't focusing on it and are instead just ignoring the issue. It's not the best decision, but given the problems of today this seems comparatively easy. It just doesn't have much urgency compared to actually building green generation capacity and batteries at scale.

Re: Canadian provinces band together to develop nuclear reactor technology

#205

Earlier quoted context omitted.

It's not. Nuclear fission reactors are built by large corporations like General Electric and Hitachi. If these companies wanted to they have the expertise to build a nuclear bomb but why would they unless their governments asked them to?

A huge number of 74 year old technologies are available for $0.75 direct from China. The fact the nuclear reactor hasn't been miniaturized to the size of a coin and included in every $15 childrens toy to power lights is in large part because of public perception and government regulation rather than real safety/health concerns - there exist plenty of typical household materials that are more dangerous than the safest…

Nuclear technology scales horribly downwards so even in a world that fully-embraced the technology you won't have pocket reactors that do anything more than maybe a power some gimmick accessory. The true power potential of nuclear only comes into affect with full steam boiler-turbine infrastructure, which are large, heavy, and maintenance-intensive beasts; a good comparison would be an early-industrial coal steam boiler from the time before we really understood metallurgy. You'd have those boilers in factories, ships, and trains, and maybe even a small crappy one if you were rich for the home workshop, but nothing you'd carry around.

RTGs can be made small, but they also completely sacrifice the power density of nuclear due to their abysmal efficiency. Their main advantage is maintenance-free longevity more so than compactness or anything.

Re: Canadian provinces band together to develop nuclear reactor technology

#206

Earlier quoted context omitted.

Stop comparing solar and wind to nuclear. That’s a cudgel to ignore the fact that being anti-nuclear means being pro-fossil fuels. Bringing online solar and wind does not displace nuclear because they do not provide a stable base. You highlight that storage is a challenge, but it’s the entire blocker at this point. Until storage is solved, solar/wind do nothing more than displace some peaker plants.

Nuclear power generation also implies using fossil-fuels powerplants. Even in 'all-nuke' France 7 to 11% of the powergrid is produced by fossil-fuel plants. This could be alleviated thanks to decentralized production (small units). Granted, this is theoretically true for nuclear and solar/wind alike, however civilian practical small solar/wind units do exist, nuclear units don't. Many write just as if nuclear plants…

France could have gone 100% nuclear, french nuclear reactors can adapt their load to the demand intra-day. It is not a technical decision.

Re: Canadian provinces band together to develop nuclear reactor technology

#207

A few years ago Toshiba was going to build a small reactor in Alaska. https://en.wikipedia.org/wiki/Galena_Nuclear_Power_Plant But it got canceled, and for the life of me I can't understand why anyone thinks its better to truck in heavy fuel oil for generators vs having a small reactor buried in the ground for 30 years. I've been saying for a few years now that green energy only advocates are basically on the side of…

The problem your comment doesn't mention is that new build nuclear is VERY expensive, far more expensive than renewables. Until new-build nuclear is MUCH cheaper, natural gas and renewables will be the vast majority of new capacity additions. All one need do is look at the debacle in South Carolina to see how expensive nuclear can truly be:

https://spectrum.ieee.org/energywise/energy/nuclear/abandone...

Re: Canadian provinces band together to develop nuclear reactor technology

#208
post #143

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Sure sounds great, what are the best and worst case costs of storing that stuff for how long? And yes i know dry cask storage is much less problematic, but i would still want a realistic plan of what is happening to that stuff and what this is going to cost. What irks me so much is that i am not simply told, look here it what it currently costs, how it would scale and what the realistic liabilities are. If you were a…

Are we all aware that nuclear power plants pay for waste disposal as part of their electricity sales cost in a trust fund called the Nuclear Waste Fund that has a balance around $50B in the US at the moment? https://en.wikipedia.org/wiki/Nuclear_Waste_Policy_Act#Nucle... As far as I know, nuclear is the only energy source that pre-pays for waste disposal.

I am not familiar with the US system. The problem in Germany is they pay a lot less then what it actually costs to "dispose" of the waste, since we dont have a method to dispose it. Hence the subsidizing, allowing it to buy out of the waste they created and which will likely have running costs for a very long time. The same could be witnessed on a larger scale when it came to the decommissioning of nuclear power plants in Germany due to the exit from nuclear energy. It was immediately clear that the to be collected funds would not suffice.

And we are far from just storing that stuff cheaply in a safe and secure storehouse we have moronic ideas like https://en.wikipedia.org/wiki/Asse_II_mine where we have to dig out old longterm storage.

Re: Canadian provinces band together to develop nuclear reactor technology

#209

Earlier quoted context omitted.

Only if the “green energy” people actually had that much power... In reality there are 2 forces that have stopped nuclear. NIMBYism. And terrible economics. But the green energy people are an easy punching bag for the nuclear advocates who are simply unwilling to face up to the reality of why nuclear keeps failing to take off.

The green energy people have massive amounts of power. They are the reason solar and wind is being built all over the world at an astonishing rate. Their lack of support for nuclear as a base-load is a major factor in its stagnation. In the US a Democrat at the federal level who doesn’t support green energy will be sentenced to the gas chambers. That’s more than half of the House of Representatives and nearly half of…

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Re: Canadian provinces band together to develop nuclear reactor technology

#210

Earlier quoted context omitted.

Small nuclear plants are actually something that can possibly help (differently from the large ones). But I doubt anybody will get the costs down enough to make them viable, wind and solar are power horses. It's like creating a non-mainstream computer architecture at the 90's and early 00's, it won't improve fast enough to even match their speed. About emissions, coal is responsible for a huge share of emissions on e…

> But I doubt anybody will get the costs down enough to make them viable [citation needed] This was discussed recently and I really down understand the immense skepticism exhibited on HN (and in general) towards nuclear energy. Sure it's expensive now, but it's been misregulated into a pulp and all extant nuclear reactors are using decades old designs. AND you need to compare the cost of nuclear to renewables PLUS st…

You are really asking for a citation of my opinion?

Besides, did you get to the next phrase? Nuclear won't beat the research investment on renewables on the next decades, because our society is starting to organize around the later. Your handful of institutions will not be able to produce more than literally everybody else.

As much as small reactors can improve, renewables will improve faster, and the floor for solar costs is very, very low.

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