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Fusion energy breakthrough by Livermore Lab

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Re: Fusion energy breakthrough by Livermore Lab

#181
post #82

I don't yet understand why this is better than Fission. Surely Fission provides us with unlimited carbon free energy (given enough fissionable material). What will Fusion give us that Fission can't already? Is it safer perhaps?

Issues of potential output and safety considerations aside:

> Surely Fission provides us with unlimited carbon free energy (given enough fissionable material).

The crux of the problem is, there is a limited supply of fissionable material. If we manage to survive as a species, our energy demand will continue to grow, and one day we would meet a hard cap, limiting what humanity as a species, is able to do.

As a very very rough estimate, if we burnt through all the fissionable material that we have available on earth, it would be about enough energy to launch the mass of Mt. Everest into orbit. Long term (as in, many generations from now) we will need more energy than that.

Re: Fusion energy breakthrough by Livermore Lab

#182

Earlier quoted context omitted.

I believe the tritium issue is addressed through the inclusion of lithium in the reactor's inner blanket [1]. Something about the neutron interaction with the lithium results in some non-trivial production of tritium which is then freed into the reactor. tl;dr - they've thought of that. [1] https://en.wikipedia.org/wiki/Breeding_blanket

My understanding is that this is proposed, but has not yet been tested. In fact, one of the goals of ITER is to test various breeder blanket designs.

Isn't this the case with nearly every aspect of "proposed" fusion reactors. Just because it's proposed or "not yet tested on a commercial fusion reactor" does not necessarily mean that the mechanism is not well understood.

Re: Fusion energy breakthrough by Livermore Lab

#183
post #74

Earlier quoted context omitted.

Are solar + batteries feasible to heat every house in Minnesota with electricity when it's below -20F (-30C) for a week, we have > just show your math. I admit I can't. It's mostly gut-feeling from various science news sources I keep up with (e.g. Ars Technica; Skeptic's Guide to the Universe).

I honestly wonder if large scale population of the northern areas is feasible without carbon fuels. Historically chopped wood was used to heat northern homes and camps, later coal and oil and I guess now to some extent electricity, but as you say, renewable energy doesn't apply there. If places like Minnesota are a net negative for green/renewable energy, their costs may be much higher to offset generation in more fa…

Not are carbon fuels are carbon negative - biofuel pulls down carbon from the atmosphere when it's created, so is considered carbon neutral.

I think it's highly likely we'll be burning a lot of algae fuel in the coming decades in situations where the energy density of carbon fuels is necessary.

Re: Fusion energy breakthrough by Livermore Lab

#184
post #74

Earlier quoted context omitted.

Solar and batteries are already cheaper than fossil fuels in most markets. Nuclear isn’t competing with renewables, it’s competing against batteries and almost free renewables that charge them. Nuclear is still possibly a great fit for niche locales where renewables aren’t feasible at all. Not a nuclear hater by any means (we need every innovation we can get), just show your math. https://www.science.org/doi/10.1126/…

Are solar + batteries feasible to heat every house in Minnesota with electricity when it's below -20F (-30C) for a week, we have > just show your math. I admit I can't. It's mostly gut-feeling from various science news sources I keep up with (e.g. Ars Technica; Skeptic's Guide to the Universe).

In central California with ideal conditions, one day’s worth of storage roughly doubles the price of a solar system that is correctly sized for net zero production in November (assuming a wood stove is supplementing a heat pump).

I don’t think storage will be feasible in places like Minnesota. The following makes far more economic sense:

- Double solar / wind production by buying 2x more panels vs. “normal” states.

- Go all electric (heat pump / induction) for appliances and vehicles.

- Buy 8-24h worth of house batteries.

- Use a fossil fuel generator to top off batteries during outages (this more than doubles the generator’s end to end efficiency)

- Sell excess electricity to the grid, where it is used for subsidized carbon capture.

This should be completely resilient against storms and power outages, and extremely carbon negative. It would cost about 2x as much as best case renewables.

Re: Fusion energy breakthrough by Livermore Lab

#185
post #151

Earlier quoted context omitted.

Because it's A) true, B) relevant to keep all of the hype in check. The year of Linux on the desktop is always right around the corner too. Yes, they are tropes, but they were not born out of nothing. Someone has to keep the bloviated PR campaigns checked with reality. Otherwise, some crazy fools might actually start believing that fusion is real and gets duped out of their money. If you can't stand a bit of real cri…

It's not a trope; it's a cliché. There's nothing wrong with poking holes in overinflated hype, but do they have to be so boring and repetitive about it.

If you keep telling me the same thing with the same lack of results, I could say the same to you as being boring and repetitive. Just because you say 2+2=5 and someone tells you you're wrong every time doesn't mean they are boring and repetitive.

Re: Fusion energy breakthrough by Livermore Lab

#186
post #74

Earlier quoted context omitted.

Are solar + batteries feasible to heat every house in Minnesota with electricity when it's below -20F (-30C) for a week, we have > just show your math. I admit I can't. It's mostly gut-feeling from various science news sources I keep up with (e.g. Ars Technica; Skeptic's Guide to the Universe).

I think UMN did a study with 4 hour storage plus solar on the grid a few years back. https://energytransition.umn.edu/modernizing-minnesotas-grid...

Thanks, this was informative. It wasn't clear to me, but I think the study does not account for switching heating from burning NG in the dwelling to electricity. I don't have numbers, but I'm pretty sure that's going to introduce an enormous load on the system, and is my main source of skepticism for wind/solar/storage as a solution for all electricity generation in places like Minnesota.

Re: Fusion energy breakthrough by Livermore Lab

#187
post #110

Earlier quoted context omitted.

> Once again, I am reminding HackerNews that the technology to build a battery capable of storing enough renewable electrical energy for the (world|nation) for even half a day does not exist at any reasonable cost. But it is almost certainly closer to existence than fusion.

Almost certainly not. The US alone generates 4,095 billion kWh yearly. For a half a day, you would need to store 5,600,000,000 kWh. Tesla Megapack can store 3916 kWh fully loaded. This means you would need 1,430,000 Megapacks to power the US for half a day. With Tesla only being capable of producing roughly 40,000,000 kWh of Megapacks annually, it would take 140 years to produce all the batteries. If Tesla created 10…

I have listed 5 different types of batteries than Tesla makes. A number more are much farther than the fundamental science stage of Fusion. Tesla primarily makes batteries for cars, grid storage is actually way more flexible in the type of battery that can be used. You are missing the forest for the trees.

Re: Fusion energy breakthrough by Livermore Lab

#188
post #162

Earlier quoted context omitted.

Because it's A) true, B) relevant to keep all of the hype in check. The year of Linux on the desktop is always right around the corner too. Yes, they are tropes, but they were not born out of nothing. Someone has to keep the bloviated PR campaigns checked with reality. Otherwise, some crazy fools might actually start believing that fusion is real and gets duped out of their money. If you can't stand a bit of real cri…

It's not true. The original quote was 30 years given current funding. They reduced the funding and surprise surprise it didn't get done. It's like when you estimate how long a project will take given a thousand people, and they reduce the number of people on the project to one person and then hold you to the original estimate.

Okay, but then if the funding has decreased, what hasn't the "years away" increased? No, that wouldn't sound good in a press release now would it. So they keep saying it is just around the corner. It's like the religious people saying that the second coming is right around the corner for over a thousand years now. I know, I know, religious zealots and science (zealots?) are different. Or are they?

Re: Fusion energy breakthrough by Livermore Lab

#189

Earlier quoted context omitted.

Bad news then. You most assuredly rely on natural gas from Texas traveling through a long underground pipeline to heat your homes and businesses. Relying on solar electricity from Texas or Arizona traveling through a long wire isn't going to change the status quo much.

> most assuredly rely on natural gas from Texas traveling through a long underground pipeline to heat your homes and businesses Last I checked, we mine our own coal, pump our own oil and put up our own wind farms [1]. Minnesota, for what it’s worth, runs on renewables, coal and nukes [2]. The fifth of natural gas it does use comes from Canada, the Dakotas and Iowa. These cold-state energy security concerns are a big…

In northern states almost all residential energy use is heating. The amount of electricity used is minimal, therefore even modest amounts of electricity generation can meet need. Wyoming is the only northern state that has natural gas in notable amounts, all other states import a lot of their energy (especially heating) needs.

If most states stopped importing energy they would have to go back to wood and coal-fired stoves. That would be a huge quality of life reduction in terms of convenience and home air quality.

Re: Fusion energy breakthrough by Livermore Lab

#190

Earlier quoted context omitted.

or fusion. There are always these articles: net energy gain finally! and then: no not really.

Reminds me of solar. That took a century to get to where we are today where the net energy output is much greater than the energy needed to manufacture them. It being hard and it requiring continual progress does not mean that progress does not occur.

Correct. Nuclear fusion research should be funded and realistic goals be set.
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