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Ultra Safe Nuclear

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Re: Ultra Safe Nuclear

#531

Post by atlasunshrugged »

manfredo wrote: post #182
atlasunshrugged wrote: post #164

Earlier quoted context omitted.

As a Nevadan who is semi-involved in local politics, I can also tell you that Yucca is so contentious and such a career killer for politicians that I have no doubt that any Nevada state or local agencies would be under tremendous pressure to find any and all reasons to make Yucca an unacceptable place to store the used material.

Is it really? Yucca mountain is basically right next to the site where the military conducted over a hundred nuclear weapons above ground, and a few hundred more below ground. Putting nuclear waste in an area that's already contaminated essential presents no change.

Yes, and that history is partly why people in Nevada dislike the idea of more nuclear waste there. Here's an article from a local paper about it https://lasvegassun.com/news/2020/aug/23/nevada-is-winning-t...

Re: Ultra Safe Nuclear

#532

Post by shakezula »

pfdietz wrote: post #353
shakezula wrote: post #122

Earlier quoted context omitted.

Nuclear is the only way we’re going to be able to get ahead of climate change. Renewables do not have the energy density required at this point. In the 70s? Sure, we might have been able to get ahead of it. At this point, we’re going to need nuclear whether we like it or not. Nuclear is the only option that will provide enough power to both scrub out existing carbon from the atmosphere and reduce our output of carbon…

This is a nonsense argument. How does the energy density of renewables prevent them from providing all the energy we need? Show us the quantitative argument (spoiler: you will not be able to do so.)

It’s not about total capacity they can provide, it’s how quickly and efficiently they can provide a unit of energy capacity, and how much carbon those materials themselves produce during manufacturing. Nuclear is, across the board, more efficient. Solar simply isn’t efficient enough, strictly speaking in terms of output per unit of input, to generate the energy we will need to reverse climate change and reduce current emissions enough.

Re: Ultra Safe Nuclear

#533

Post by pfdietz »

shakezula wrote: post #532
pfdietz wrote: post #353

Earlier quoted context omitted.

This is a nonsense argument. How does the energy density of renewables prevent them from providing all the energy we need? Show us the quantitative argument (spoiler: you will not be able to do so.)

It’s not about total capacity they can provide, it’s how quickly and efficiently they can provide a unit of energy capacity, and how much carbon those materials themselves produce during manufacturing. Nuclear is, across the board, more efficient. Solar simply isn’t efficient enough, strictly speaking in terms of output per unit of input, to generate the energy we will need to reverse climate change and reduce curren…

Carbon produced during manufacturing is a bad metric right now. If producing a MW of levelized capacity for solar (say) causes emission of twice the CO2 of a MW of nuclear, but displaces much more CO2 of fossil emission per $ invested than nuclear, then going with solar displaces more CO2 than going with nuclear, for a given investment budget.

Also, the CO2 emission is a function of the level of fossil fuel use remaining in the rest of the economy. Transporting materials to the site depends on whether those vehicles are burning fossil fuels or not, for example. The focus on current CO2 from manufacturing is implicitly assuming that we will always need fossil fuels to build these things, that the processes and materials can never be performed/made with non-fossil inputs. With that assumption, we're doomed, so the difference is irrelevant anyway.

Re: Ultra Safe Nuclear

#534

Post by DennisP »

DoctorOetker wrote: post #530
DennisP wrote: post #469

Earlier quoted context omitted.

If you're going to shut down factories at night, that itself is a cost that should be accounted for. If you're shutting down for eight hours a day, you increase capital costs by a third. That's worth paying if it's the only option to address climate change, but if the main argument against nuclear is cost, it's not a fair comparison if renewables externalize cost to the customers. (Also, aluminum smelters in particul…

why don't they store the cheaper day time electricity by melting extra on site aluminum during the day? this aluminum could stay on site indefinitely?

The aluminum freezes in about six hours, that's why they take damage if they lose power.

Re: Ultra Safe Nuclear

#535

Post by loeg »

7952 wrote: post #529
loeg wrote: post #522

Earlier quoted context omitted.

It'd help to stop repeating mostly false stories (and leading questions) about Chernobyl, Three Mile Island, and Fukushima every time nuclear comes up. But how to persuade the general public that science and statistics matter when even HN is skeptical? You're right, I don't know how to do that.

Science works because you are able to control most of the variables. It simplifies the world into something that can be modelled. Major decisions like energy policy are just more complicated than that. It is hundreds of overlapping considerations that have no good single answer. Yes science still matters, but there are deeper political questions at play. You just need to accept that if you want to build big complex t…

I disagree with your entire premise and do not believe we can fruitfully come to any common ground. So, I guess we can agree to disagree.

Re: Ultra Safe Nuclear

#536

Post by DoctorOetker »

DennisP wrote: post #534
DoctorOetker wrote: post #530

Earlier quoted context omitted.

why don't they store the cheaper day time electricity by melting extra on site aluminum during the day? this aluminum could stay on site indefinitely?

The aluminum freezes in about six hours, that's why they take damage if they lose power.

its not a property of molten aluminum to freeze in 6 hours, it depends on the thermal insulation.

what I proposed was to have a secondary sealed thermal bath of aluminum which gets molten during cheap power and which returns heat during expensive power to maintain the temperature of the primary (work) batch of aluminum so that the work batch doesn't freeze

the heat can be transfered with an appropriate working fluid.

since the secondary thermal bath aluminum doesn't need to satisfy client demands (specific alloy etc) the alloy can be chosen so as to have a suitable melting point for such a setup

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