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First new U.S. nuclear reactor since 2016 is now in operation

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Re: First new U.S. nuclear reactor since 2016 is now in operation

#151

Earlier quoted context omitted.

I find it hard to imagine solar could ever be cheaper than nuclear during winter in Northern Europe.

No need to imagine, because it is. At least if you believe electricity market prices reflect reality.

What is?

> At least if you believe electricity market prices reflect reality

I don't see how is this relevant if we're talking specifically about solar.

Above ~53° solar production during December is ~20 (to way more than that farther you go north) lower than in December.

Re: First new U.S. nuclear reactor since 2016 is now in operation

#152
post #67

Earlier quoted context omitted.

One kilogram of uranium-235 (50 cm^3) can theoretically produce about 20 terajoules of energy. One square kilometer of solar panels can theoretically produce the same amount (as 50cm^3 U235) in a day. I'll take this bet. Edit: Tried to edit the edit but somehow deleted the rest of the edit. It was something to the tune of how a big problem with renewables is the fact that peak solar production does not match peak ene…

We need two things: - More energy - Energy diversification That includes nuclear, solar, and even more fossil fuels as we wean ourselves off of them. Writing off any form of energy is ideological, not practical.

Agreed minus the fossil fuels bit. It's my belief we should not further scale that infrastructure.

Re: First new U.S. nuclear reactor since 2016 is now in operation

#153

Earlier quoted context omitted.

One kilogram of uranium-235 (50 cm^3) can theoretically produce about 20 terajoules of energy. One square kilometer of solar panels can theoretically produce the same amount (as 50cm^3 U235) in a day. I'll take this bet. Edit: Tried to edit the edit but somehow deleted the rest of the edit. It was something to the tune of how a big problem with renewables is the fact that peak solar production does not match peak ene…

Perhaps I fail to understand, but doesn't this comparison depend on a number of parameters such as the total reactor fuel load and enrichment, the burn rate, the cost of nuclear fuel, the cost of solar PV, the lifetimes of each system, and the relative process efficiencies (notably the cost of decommissioning nuclear)? Otherwise you might as well say a teaspoon (or whatever) of water has as much potential fusion ener…

Small nitpick: one teaspoon of water has much less potential fusion energy than 1 kg of U235, and actually much much less than 1g of U235, even allowing for fusion technology that does not exist and will not exist in 50 years.

Here's why.

The Sun transforms hydrogen into helium. But that's a fairly complex chain and nobody in the industry or academia is trying to replicate that.

When people talk about fusion, here's [1] the reactions they are considering.

The best yielding fusion reaction is deuterium-tritium and deuterium-helium3 [1]. Tritium and helium-3 virtually don't occur naturally on Earth, and deuterium is very rare, at about 0.02% of the hydrogen. A teaspoon of water contains about 0.5 grams of hydrogen, and out of that about 0.0001 grams of deuterium. Let's say that someone magically brings the necessary tritium or helium-3. How does that compare with 1 gram of U235?

The fission of 1 nucleus of U235 yields about 190 MeV of energy. 1 MeV is one megaelectronvolt, and is a unit of energy. It does not matter how it translates into joules or watt-hours. It is the unit used when talking about fission and fusion. So, 235 nucleons produce 190 MeV, which is about 0.8 MeV per nucleon.

The two reactions mentioned involve 5 nucleons and yield about 18 MeV, which means 3.6 MeV per nucleon or 4.5 times more per nucleon than U235.

So, even if all the hydrogen in the one teaspoon of water was Deuterium and Tritium, in the correct ratios to do the fusion, we'd get only 4.5 times more energy than from one gram of U235. In reality, from one teaspoon of water we'd extract a very tiny amount of deuterium that's usable, and we'd need to breed Tritium or Helium-3 separately. By the way, separating deuterium from water is a very expensive process. The Nazis tried to do it during WW2, and they were doing it in Norway. Once the British special forces destroyed the plant, the Nazis could not restart the heavy water production, and their atomic project basically stopped then and there.

[1] https://en.wikipedia.org/wiki/Nuclear_fusion#Criteria_and_ca...

Re: First new U.S. nuclear reactor since 2016 is now in operation

#154

Seems to me the people saying solar and battery only future do not live in areas that can be cloudy for multiple weeks. I didn’t run the math but I’m guessing it’s not feasible to build a battery pack large enough to ride out winter in some areas. The SF Bay Area, sure, but I suspect blackouts will be common in solar+battery only areas. A preferred solution would be a mix of both with nuclear handling disruptions due…

Batteries are not for riding out winter, they're for evening out the daily load. You have to overbuild renewables to handle seasonal variation, as well as make long-distance interconnects. Pumped hydro is also extremely interesting for obvious reasons. Nuclear as it exists today is not cost competitive. But that's mostly an artificial problem caused by regulation. Can we solve that without sacrificing safety? Can we…

One benefit of building excess capacity of renewables - free electricity to power your automobile. If we actually priced excess energy smartly people would charge their cars in the daytime and spend ~ 0 to drive most of the year.

Re: First new U.S. nuclear reactor since 2016 is now in operation

#155

Seems to me the people saying solar and battery only future do not live in areas that can be cloudy for multiple weeks. I didn’t run the math but I’m guessing it’s not feasible to build a battery pack large enough to ride out winter in some areas. The SF Bay Area, sure, but I suspect blackouts will be common in solar+battery only areas. A preferred solution would be a mix of both with nuclear handling disruptions due…

> Seems to me the people saying solar and battery only future do not live in areas that can be cloudy for multiple weeks. This isn't a big problem. Wind is negatively correlated with solar, and electricity can be sent across long distances (intra- or inter-country) with minimal loss, and overbuilding eliminates a lot of the variability issues. Variability across geographies and across modes cancels out. Nuclear is pr…

Wind is negatively correlated with solar

Yes, but not strongly. It is definitely a problem, as seen in Texas on cold mornings where solar isn't getting much light, winds are still, and people need heat.

Re: First new U.S. nuclear reactor since 2016 is now in operation

#156
post #12
post #2

See also: "Georgia nuclear rebirth arrives 7 years late, $17B over cost" https://apnews.com/article/georgia-nuclear-power-plant-vogtl... https://en.wikipedia.org/wiki/Vogtle_Electric_Generating_Pla...

This is always the case when you build large one-off projects. If you continue to build reactors non-stop you'll learn how to make the process more efficient and be able to make better estimates. Surely we software developers should appreciate how hard making accurate estimates is? And this isn't a 2 week sprint we're talking about, but a gigantic engineering project.

These were not one-off reactors, it's just that the first ones went so poorly that everything else was cancelled. There were four that were started at roughly the same time. There were many other sites getting order ready.

Westinghouse used a new regulatory process that had been created specifically at the request of industry to speed the design and build of AP1000s. Despite this, Westinghouse did not deliver constructible designs, and the contractor soldiered on with on site modifications. Westinghouse screwed up so bad that they nearly bankrupted Toshiba, their owner.

So we have two failed holes in the ground at Summer in South Carolina, something like a $10B monument to corruption, with utility execs going to jail for their fraudulent reports.

All the other sites that were eyeing AP1000s to replace aging reactors have now backed out. The disaster was too big. What exec wants to go to jail for a nuclear reactor? What exec wants to lose their job for greenlighting what has a not-insignificant chance of bankrupting the entire utility.

Nuclear is too risky, but public perception is off, it's not running reactors that have the risk, it's the financial risk to anybody who wants to build one.

Re: First new U.S. nuclear reactor since 2016 is now in operation

#157

Seems to me the people saying solar and battery only future do not live in areas that can be cloudy for multiple weeks. I didn’t run the math but I’m guessing it’s not feasible to build a battery pack large enough to ride out winter in some areas. The SF Bay Area, sure, but I suspect blackouts will be common in solar+battery only areas. A preferred solution would be a mix of both with nuclear handling disruptions due…

Batteries are not for riding out winter, they're for evening out the daily load. You have to overbuild renewables to handle seasonal variation, as well as make long-distance interconnects. Pumped hydro is also extremely interesting for obvious reasons. Nuclear as it exists today is not cost competitive. But that's mostly an artificial problem caused by regulation. Can we solve that without sacrificing safety? Can we…

> an artificial problem caused by regulation

Maybe it's a real problem caused by the physical realities of nuclear. Calling regulation an artificial cost is like calling sewage treatment an artificial cost of water.

> Bloated regulatory agencies seem to have infiltrated and poisoned every aspect of society with no relief in sight.

It's often repeated, including by a certain political grouping, but never established IME. Unregulated markets, such as cryptocurrency, privacy, etc. seem to cause most of the problems. The FAA, etc. do well IME. They fail when undermined by a political class that benefits from fraud (the same trying to prevent the IRS from collecting legitimate taxes.)

Re: First new U.S. nuclear reactor since 2016 is now in operation

#158

Seems to me the people saying solar and battery only future do not live in areas that can be cloudy for multiple weeks. I didn’t run the math but I’m guessing it’s not feasible to build a battery pack large enough to ride out winter in some areas. The SF Bay Area, sure, but I suspect blackouts will be common in solar+battery only areas. A preferred solution would be a mix of both with nuclear handling disruptions due…

It doesn't make any sense to use nuclear as a standby source of power. Nuclear costs pretty much the same whether you use it or not, so it doesn't make any sense to build it and leave it off.

So if you build a nuclear power plant, save yourself the cost of whatever else you wanted to use as a primary source.

Re: First new U.S. nuclear reactor since 2016 is now in operation

#159

Earlier quoted context omitted.

No need to imagine, because it is. At least if you believe electricity market prices reflect reality.

What is? > At least if you believe electricity market prices reflect reality I don't see how is this relevant if we're talking specifically about solar. Above ~53° solar production during December is ~20 (to way more than that farther you go north) lower than in December.

And still, PV generated electricity during these periods is priced cheaper on the spot market than nuclear. Funny, right? It is almost as if the parties investing billions and making billions selling and buying electricity figured out the financials behind all that.

Re: First new U.S. nuclear reactor since 2016 is now in operation

#160

If I was a betting man, I would put money down that Vogtle 4 is the last nuclear reactor that gets built in the US. Solar and batteries are just too cheap for nuclear to compete. The world will be installing a terawatt of solar capacity per year soon. *excluding research or military reactors of course.

One kilogram of uranium-235 (50 cm^3) can theoretically produce about 20 terajoules of energy. One square kilometer of solar panels can theoretically produce the same amount (as 50cm^3 U235) in a day. I'll take this bet. Edit: Tried to edit the edit but somehow deleted the rest of the edit. It was something to the tune of how a big problem with renewables is the fact that peak solar production does not match peak ene…

The uranium can produce power when it's dark outside, unlike the solar panels. I wouldn't bet against clean energy that can produce on demand. We'll always need it from somewhere.
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