this post was submitted on 01 Aug 2023
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Oh, neat. My state did something not completely stupid. I've got some reservations about nuke power as opposed to renewable, but this is definitely better than continuing fossil fuels.
Fission and fusion reactors are really more like in-between renewable and non-renewable. Sure, it relies on materials that are finite, but there is way, way more of that material available in comparison to how much we need.
Making this distinction is necessary to un-spook people who have gone along with the panic induced by bad media and lazy engineering of the past.
Fusion and fission are quite different. A practical fusion reactor does not exist. It's outside our technological capability right now. Current fusion reactors are only experimental and can not maintain a reaction more than a small fraction of a second. The problem is plasma containment. If that can be solved, it would be possible to build a practical fusion reactor.
The fuel for a working fusion reactor would likely be deuterium/tritium which is in effect unlimited since it can be extracted from seawater. Also the amount of fuel required is small because of the enormous amounts of energy produced in converting mass to energy. Fusion converts about 1% of mass to energy. Output would be that converted mass times the speed of light squared which is a very, very large number, in the neighborhood of consumed fuel mass times 10^15^.
Fusion is far less toxic to to the environment. With deuterium/tritium fusion the waste product is helium. All of the particle radiation comes from neutrons which only require shielding. Once the kinetic energy of the particles is absorbed, it's gone. There's no fissile waste that lingers for some half life.
Here's something more interesting. A matter-antimatter reactor converts 100% of mass to energy so it's a hundred times more efficient than fusion. In modern times antimatter has been produced at quantum levels in large accelerators such as the Hadrian collider. So it does in fact exist and can be produced.
However a matter-antimatter reactor has some serious technical problems. For one it's currently impossible to create antimatter in any practical quantity. Second if antimatter comes in contact with matter, instant boom. Like a sugar cube size of the stuff could level a large city. So containment would be an insurmountable problem.
The interesting part is when you see an antimatter reactor in shows like Star Trek, it's based on real science. Interestingly in 1968 when they wrote the original Star Trek, nobody knew antimatter was a physically real thing. That's a case of sci-fi predicting science.
But antimatter needs energy to create, probably more energy than it can produce. Unless you can find some source of it in the environment. Fusion is much more likely to be feasible.
Antimatter might make a good compact way to store energy for a starship, if it was created in a large fixed facility with access to huge power sources. But it's not a way to generate energy by itself.
I was just future proofing my comment for things like this: https://youtu.be/_bDXXWQxK38
Your info is a little out of date - some fusion experiments have been able to maintain fusion for almost a minute. However, your point still stands. We are decades away at a minimum untill a viable fusion reactor.
My guess is that fusion will be too expensive for commercial use unless they can get a super compact stellarator design to produce huge amounts of energy, and make them cheap to build (HA!).
Or we will see them in spaceships. :P
LWR fuel is incredibly limited without a massive fleet of breeders (and no breeder has ever run a full fuel cycle, nor has second generation MOX ever been used. First generation MOX is also incredibly polluting and expensive to produce).
The industry is already on to tapping uranium ore sources that are less energy dense than coal, and this is to provide a few % of world energy for a handful of decades.
Not trying to be "difficult," but isn't that what people thought about coal/oil at first? I understand that the scale is different, but it still needs to be a stop gap as opposed to a long term plan.
Spent Nuclear Fuel, unlike coal or oil, can be recycled to a certain extent (this is done in places like France but not the US). If we recycled all of the spent fuel, we'd potentially have a thousand years (give or take) of fissionable fuel. Plenty of time for us to get fusion running so we can completely wean ourselves off petroleum energy generation.
billions if we start using thorium
So far the problem, if I understand correctly, is all thorium reactors are molten salt reactors. The issue there is, we still haven't solved the metallurgy problems of dealing with the corrosive salt. It destroys all the pipes. We have slowed it down, but not enough to go production with.
By that time I'm hoping we'd be using Deuterium-Tritium fusion for all our needs. Or go full scale megaengineering and Dyson Sphere some star somewhere.
Why do you think we need nuclear to transition fully off petroleum? Renewables with storage are cheaper today for new build power, let alone in another 20 years. They continue to get cheaper and more efficient quite rapidly.
Because renewable depends on the weather, while nuclear doesn't.
A mix of renewable is absolutely a good thing to do, but still, having a constant source of energy mixed with that ensure stability.
The storage problem is the limiting factor. Batteries are wildly too expensive, pumped storage takes a huge amount of space and isn’t feasible in most places due to geography, and hydrogen is not nearly there yet technologically.
If we switched entirely to wind and solar we would need to accept total shutdowns when we had a bad run of weather.
last time I checked the renewables being installed didn't even offset the new energy demands being created, let alone making a dent in starting to decarbonize existing demand.
and the main reason is, that we need to tackle climate change from as many angles as possible and not eliminate a fine energy source just because something else is cheaper.
I mean for now renewables are cheaper, do you think we have enough raw materials to cover all of earths energy needs?
what happens when the raw materials will start to run dry but we still need to cover a bunch of energy needs, is that when we dust off the good ol Nuclear plants?
not to mention Nuclear plants provide a stable base load, no need for smart electronic devices that use power when it's most abundant etc. it's just power, that runs, constantly.
I think the issue is batteries, which are expensive and require rare earth metals which often have environmentally costly acquisition methods. Perhaps an optimal solution would be a baseline of nuclear power, and then enough renewables to meet peaks in demand. That way we have plenty of stable energy while minimizing nuclear risks.
When you get into power say a whole large city the batteries cost more then the solar panels. Especially in more polar places like Juno Alaska where you need to store a surplus of power for months. plus batteries degrade over time so they would have to be replaced. That's part of the reason why ion flow batteries are being researched, you can just drain them and replace the fluid*.
I didn't know about those. I'll have to look more into it. Thanks!
Adding to what others have said here, nuclear is great for base load consumption. Use the renewables to supplement during peak hours where load variability is the greatest.
Sure, you could connect renewables to batteries / accumulators for times when they are not available (i.e. no wind, no sun) but this doesn't give a very good consistent base load. A nuclear plant that is 1 MWe will always give 1MWe if it is up all the time. I'm not saying here that batteries aren't a good option, just that they aren't the optimal solution.
Another thing to consider is resistive transmission losses. Connecting long cables from, say offshore wind farms or areas of high wind density, to electrical substations long distances away makes delivering the electricity more inefficient. Granted, having it is better than not (nobody likes brownouts). But engineers try to take all of these into consideration when working on the regional power grid.
If we can pull off hydrogen fusion without crazy radioactive isotopes I reckon we can go on for a little while without having to worry about running out of hydrogen in the solar system / galaxy
Instead we only have to worry about immediately running out of beryllium for breeding blankets just on the demo reactors.
We don’t even know if fusion will ever be functionally able to produce more energy than it consumes, and on top of that it will need to be less expensive than natural gas or solar in order to compete. Which it will never do. Do you have any idea how much ITER has cost?
$22 billion, or $16 billion “over budget.” And this is a test reactor that will never produce commercial power. They still have 2 years of construction left so… it could hit $30 billion. At least at Vogtle they are getting two reactors.
We can still categorize a concept, even if the technology doesn't exist in a useful state yet.
Too bad the energy companies essentially never dispose of the waste properly, because it's too expensive if they want to give the huge bonuses to their CEOs and buyback thie stock. Even when doing it "properly" it's basically just making it the problem of future generations once the concrete cracks.
And to reprocess the waste and make it actually safe energy would mean no profit at all plus the tech doesn't exist yet to actually build the reactors to reprocess the waste. I mean we understand the theory, but it would take at least a decade to engineer and build a prototype.
Compare that to investing in battery tech which would have far reaching benefits. And combining that with renewables is much more profitable.
To be fair, nuclear waste tends to be disposed of much more properly than coal waste.
There's also orders of magnitudes less.