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Ultra Safe Nuclear

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Re: Ultra Safe Nuclear

#361

Post by Raidion »

pfdietz wrote: post #331
macspoofing wrote: post #323

Earlier quoted context omitted.

>it costs 3-10x what the equivalent generating capacity in renewables would cost Except renewables can't actually replace fossil fuels. They need baseload provided by fossil fuels to be viable. They are also defuse energy sources, and so require huge surface area and lots of materials for collectors - not great for a growing world, both in population and per capita energy needs. Oh, they are variable across days, sea…

> Except renewables can't actually replace fossil fuels. They need baseload provided by fossil fuels to be viable. False. Renewables could get to 100% of the grid. A key is using hydrogen for the last 10% or so. This is not currently competitive with fossil fuel, but then neither is nuclear.

I'm not an expert in this, but isn't this just a really extra lossy type of battery? Hydrogen takes energy to create, so if you're creating hydrogen from renewable energy sources during peak load, you have to go energy -> hydrogen -> energy with efficiency losses both ways. I remain unimpressed by hydrogen, as it seems to only be practical if you don't any other options for existing stores of energy. For instance a large scale battery system, or even some mechanical energy storage systems.

Re: Ultra Safe Nuclear

#362

Post by bananabreakfast »

8bitsrule wrote: post #316
alextheparrot wrote: post #265

Earlier quoted context omitted.

This is an incredibly weak argument, as most of the opposition to nuclear power even before widespread renewable deployment was political, not economic. Maybe the economics have changed with renewables, but that needs to be proved rather than can be inferred by the lack of US reactors being built. Take Germany’s recent denuclearization, the efforts are completely political, there was no mention of balance sheet optim…

>most of the opposition to nuclear power even before widespread renewable deployment was political, not economic. Most of the opposition to nuclear power was about a whole lot of things other than politics or economics. Decades of quantifiable failure after failure in the environmental, construction quality, maintenance, radioactive discharge, siting-safety, and waste-handling realms, to name just a few. Everywhere t…

"Too cheap to meter" was never a promise. It is a quote taken out of context that was facetious and never meant to be taken literally.

Re: Ultra Safe Nuclear

#363

Post by sparkie »

pfdietz wrote: post #345
sparkie wrote: post #296

Earlier quoted context omitted.

> What if prices for power go way up during the night Individual energy providers do not control prices. The market does. If there is market demand for energy at night, then people will fill in the gap to provide it. Anyone pushing up prices at night will have competition from someone else who will undercut them. They'll be forced to drop prices or lose customers. Batteries are inefficient, expensive, and do not prov…

"Inefficient" = 90%? I think you need to think more about what you've written there.

As stated, that is "at most". A usual UPS is 80-89% efficient.

Even still, assuming they were 90% efficient, is it worth the extra 10% energy consumption just so you can run your computer for 1 hour at night when the solar energy provider ups their rate? You still need to consume the additional energy in the day to charge the battery.

For me to label it efficient, I'd be looking for 95%+, but 99% would be preferable.

Remember, this efficiency declines as the battery ages. You only get a few years of efficient use before it declines significantly. Then you have a disposal problem. A typical UPS uses lead-acid batteries, the same type used in cars. They're not environmentally friendly.

Re: Ultra Safe Nuclear

#364

Post by pfdietz »

bananabreakfast wrote: post #360
pfdietz wrote: post #331

Earlier quoted context omitted.

> Except renewables can't actually replace fossil fuels. They need baseload provided by fossil fuels to be viable. False. Renewables could get to 100% of the grid. A key is using hydrogen for the last 10% or so. This is not currently competitive with fossil fuel, but then neither is nuclear.

So, what? Just use hydrogen like a gigantic grid sized battery? Also, nuclear is only not competitive due to strangling regulation, not fundamentals.

Burn the hydrogen in combustion turbines, just like natural gas.

You repeat an excuse, but nuclear builds have failed, and continue to fail, not because of regulation, but because of the high unforgiving complexity of nuclear power plants. The post mortems at huge cost overruns point to management failures, not new regulations sprung out of nowhere.

Re: Ultra Safe Nuclear

#365

Post by pfdietz »

bananabreakfast wrote: post #359
pfdietz wrote: post #330

Earlier quoted context omitted.

NuScale claimed they could build their reactor in a factory too. Then that fell apart.

What? That's a pretty outrageous claim with no evidence

https://losalamosreporter.com/2020/08/22/get-out-of-the-fluo...

"In answer to a question I posed to Nuscale at the town hall we have learned that the plan to save costs by fabricating the modules at a remote factory and shipping them to the Idaho site has been abandoned. The artful response to my question said that Nuscale engaged with approximately 40 … pressure vessel fabricators worldwide and … determined that Nuscale will use existing factories … in lieu of building its own factory.

The major module subcomponents will be manufactured at multiple manufacturer locations and shipped to a single location for assembly prior to installing into the facility.” This signifies the failure of one of the major cost-saving features of the Nuscale project, which was to forestall this exact scenario."

Re: Ultra Safe Nuclear

#366

Post by bananabreakfast »

ajross wrote: post #252
Wowfunhappy wrote: post #240

Earlier quoted context omitted.

So, why did so many countries/companies originally build nuclear reactors, if the economics inherently don’t make sense? Has something changed?

To make bombs. And what's changed now is we have enough bombs. Seriously, even the reactors that aren't expressly breeding fuel were designed with an eye to the technology and as part of programs in the 50's-70's to build out expertise in this critical technology area of national security. Countries wanted bombs. To make bombs you need a nuclear industry. Ergo, everyone who wanted bombs built civilian reactors, witho…

Explain Japan's nuclear power plants.

Re: Ultra Safe Nuclear

#367

Post by bananabreakfast »

jay_kyburz wrote: post #261
ajross wrote: post #237

Earlier quoted context omitted.

And unlike a natural gas plant, it costs 3-10x what the equivalent generating capacity in renewables would cost. I come to post this Same Thing every time this discussion comes up. It's not about safety. Everyone serious understand nuclear, even current technologies, is "safe enough" to be useful to build out. Nuclear is outrageously expensive , though. And new reactor designs don't seem to be making much progress on…

Not to mention the waste which needs an armed guard almost forever, making the total cost of the energy almost infinite.

Nuclear waste only lasts "forever" when it is not recycled. And even then it is not dangerous and doesn't need an "armed guard" after a few weeks when all the most radioactive material has decayed away.

Re: Ultra Safe Nuclear

#368

Post by tgsovlerkhgsel »

jbob2000 wrote: post #126
semi-extrinsic wrote: post #87

Earlier quoted context omitted.

There was a comment here about cleanup costs of nuclear vs. solar, that was deleted while I was typing my response to that. I'm just gonna copy in my response here, because I think it's an interesting topic: Are we really sure solar panels are much easier to dismantle on a euro-per-kWh basis though? That is, if you divide the total cost of dismantling and recycling a solar power plant, divided by the total amount of…

Solar panels aren't the only way to generate energy using the sun. You can build a concentrated solar farm (see: https://edition.cnn.com/2019/02/06/motorsport/morocco-solar-... ) which uses mirrors and salt to produce up to 580mw of power, with a cost of just under $1bil. My neighbor heats their pool using solar, it's just a bunch of tubes that cycle water over their roof. They got rid of their gas heater. Given that…

If the pool needs heating while the house needs air conditioning, using the pool as a heat sink for the A/C would probably be even better.

Re: Ultra Safe Nuclear

#369

Post by pfdietz »

sparkie wrote: post #363
pfdietz wrote: post #345

Earlier quoted context omitted.

"Inefficient" = 90%? I think you need to think more about what you've written there.

As stated, that is "at most". A usual UPS is 80-89% efficient. Even still, assuming they were 90% efficient, is it worth the extra 10% energy consumption just so you can run your computer for 1 hour at night when the solar energy provider ups their rate? You still need to consume the additional energy in the day to charge the battery. For me to label it efficient, I'd be looking for 95%+, but 99% would be preferable.…

Of course it's worth it. Losing 10% of the energy in storage is close to trivial, particularly if that energy is otherwise curtailed excess production. It would be worthwhile to use far less efficient storage for long term load leveling, if the capital cost were low enough. Hydrogen with cheap electrolysers and combined cycle turbines might have a round trip efficiency of 33% -- and that would be GREAT as a last component for getting to a fossil-fuel free grid, particularly at high latitude.

Re: Ultra Safe Nuclear

#370

Post by pfdietz »

Raidion wrote: post #361
pfdietz wrote: post #331

Earlier quoted context omitted.

> Except renewables can't actually replace fossil fuels. They need baseload provided by fossil fuels to be viable. False. Renewables could get to 100% of the grid. A key is using hydrogen for the last 10% or so. This is not currently competitive with fossil fuel, but then neither is nuclear.

I'm not an expert in this, but isn't this just a really extra lossy type of battery? Hydrogen takes energy to create, so if you're creating hydrogen from renewable energy sources during peak load, you have to go energy -> hydrogen -> energy with efficiency losses both ways. I remain unimpressed by hydrogen, as it seems to only be practical if you don't any other options for existing stores of energy. For instance a l…

Yes. The advantage of hydrogen is the extremely low cost per unit of stored energy. That is the cost you want to minimize for a storage case with few charge-discharge cycles, like rainy day or seasonal storage.

For diurnal storage, batteries or other more efficient storage technologies would make more sense, since there would be more charge-discharge cycles over which to amortize the cost of the system.

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