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Nuclear "con" Fusion.

Not only Thorium, but spent fuel could also be an option. This idea from a Silicon Valley startup looks interesting - micro reactors powering at a district level, using spent fuel. The biggest single obstacle looks likely to be security. Nuclear will always be a magnet for terrorists.
I've heard of scalable modular designs in the works too. Our very own Rolls Royce is planning to build these.

I really like the idea of a large building like a skyscraper with a built in underground virtually maintenance free reactor to power the building for its lifetime...a bit like a battery.
 
It does feel viable to me for infrastructure where security and the other issues can be managed. So, airports, hospitals, rail infrastructure and so-on. I'm less sure about individual building level, for reasons of security mainly, but also I can't see commercial landlords wanting to take on the long-term responsibilities for these, unless they are clean and simple to decommission at EOL.
 
While that is brilliant news and shows how any problem can be overcome. The fast neutrinos produced by fusion are not easy to control ….

If they can control fast neutrinos they are well past the problems of nuclear fusion.:)
 
I thought the thing about neutrinos was that they barely interacted with regular matter, so what is the problem?
 
The answer is nuclear power as there is more than we need and it comes from the Sun. I have posted this before but its worth a read https://www.forbes.com/sites/quora/...-energy-from-1-of-the-sahara/?sh=305b873ad440

And there are other hot desert areas in addition to the Sahara.

Where fusion would be useful is in a starship as the resources could be collected as you travel through space.

Cheers,

DV
Fascinating, thanks DV. How might the intermittency of such large solar projects be handled without resorting to huge battery banks (which currently have their own environmental issues and add significantly to the overall Carbon Intensity of solar power)?
 
The answer is nuclear power as there is more than we need and it comes from the Sun. I have posted this before but its worth a read https://www.forbes.com/sites/quora/...-energy-from-1-of-the-sahara/?sh=305b873ad440

And there are other hot desert areas in addition to the Sahara.

Where fusion would be useful is in a starship as the resources could be collected as you travel through space.

Cheers,

DV
Like all simple and obvious solutions, it might not be as simple as you make out.

TL;DR: covering significant areas of high-albedo terrain (such as deserts) with low-albedo solar panels creates local disruption to climate as 85% of the sunlight absorbed is re-emitted as heat and only 15% goes to electricity; and, once past a critical size, could create a significant driver of global warming themselves, which could even generate a positive feedback loop stage.
 
Fascinating, thanks DV. How might the intermittency of such large solar projects be handled without resorting to huge battery banks (which currently have their own environmental issues and add significantly to the overall Carbon Intensity of solar power)?
Its already starting for the UK https://electrek.co/2021/09/27/the-...ill-send-clean-energy-from-morocco-to-the-uk/

Some years ago I read a study of how sustainable energy could be obtained from the Sun. It was huge and covered every option you could think of and the result may surprise you. Steam or hot air engines driven by solar energy driving dynamo’s. The electricity can then be used locally and stored by creating Hydrogen from sea water (electrolysis) and transported in liquid form. The analysis considered the raw materials for this process as being always available and recyclable e.g. Iron, Copper and wood unlike solar panels and rechargeable batteries that will in quite a (relatively) short time exhaust supply of the limited amount of the rare elements required that are available on this planet.

I like Hydrogen as a fuel as it can be used to generate electricity in a fuel cell and burned in an ICE both processes resulting in water.

Interesting no?

DV
 
Fusion has always been [in my lifetime] twenty years in the future. It was twenty years in the future in the 1970s, and still is today!

It seems the whole premise may be misguided ...

That is an interesting video @George J & thanks for posting. If we're to go forward, then it is important that scientist, project leaders & financiers are honest about the numbers else it will be counter productive. Sabine Hossenfelder isn't being negative, she's merely pointing out that currently, we're being misled. Clearly, the research is worthwhile, though it will most likely be a long time before mankind gets any benefit from it; obviously it wouldn't be economically viable for a commercial reactor to consume more energy than it generates!
 
You seem to have missed the point. That being that something like a 20-fold increase in conversion efficiency is required just to break-even. That would be one seriously, seriously large improvement due to scale alone.

I'd recommend you do a bit more reading on the subject.
 
Yes, that was my mistake, I should written fast neutrons instead of fast neutrinos...I'm sorry for the confusion. Neutrons from fusion captured by the nuclei of nearby containing materials will produce radioactive isotopes and weaken stuff by creating intercrystal hydrogen.... As I read from the article linked in PSB's post on page one. But lithium can capture these and generate more tritium which could possibly be cycled back into the plasma for easier (less hot) fusion.

Neutrinos are an altogether different thing... They'll be plenty produced I guess but will be of no consequence.
 
That is an interesting video @George J & thanks for posting. If we're to go forward, then it is important that scientist, project leaders & financiers are honest about the numbers else it will be counter productive. Sabine Hossenfelder isn't being negative, she's merely pointing out that currently, we're being misled. Clearly, the research is worthwhile, though it will most likely be a long time before mankind gets any benefit from it; obviously it wouldn't be economically viable for a commercial reactor to consume more energy than it generates!

Agreed on all points.

Firstly, science has to be completely honest, or else we get the devaluation of science. If they lie about things, they cease to be credible and those who would love to stay in the current "status quo" will have a field day.

Sabine is not being negative, but rather straight forward. She is correct [as you say] to point out the misleading which is definitely going on. She like me, is no "hopium" addict.

Your third point is self-evident. The power out must be more than the power in to make sense.

Finally, I should add that I am totally in favour of all avenues of experiment and development of carbon neutral and safe energy conversion to electricity.

If Fusion can be made safe and viable, then I am all for it. No omelet was made without breaking eggs. Research should be continued with vigour, but there is no need to indulge in selective data to achieve the necessary funding and priority - the problems and dangers need assessing for what they are.

I still think we have a self-sustaining and long lived Fusion reactor as the centre of our solar system, and it would be wise to maximise use of sunlight and energy storage [chemical energy as the the result of electrolysing hydrogen with excess solar power per immediate need] to balance supply and demand difference. I am not a huge enthusiast for battery storage to completely cover the difference between solar, tidal and wind power, and immediate demand. Batteries have their place to smooth out daily variations, but hydrogen storage would a allow a large buffer to be built up of accessible energy for long periods of unusual climatic conditions. Like a shock absorber or an electronic capacitor that smooths things out.

Thanks for you reply.

Best wishes from George
 

I get that (and my own employer is negative on nuclear but hugely pro on solar and wind). However there are around 50 reactors being built globally, or in advanced planning stages which is not mentioned in that report. Plus the possibilities of upcoming standardised SMR technology to really reduce capital, time to operation, and operating costs in the next 10-15 years is not to be sniffed at. The intermittency of solar and wind is a really big issue that mega-battery banks will struggle to help with (they will also impact the CI and LCOE of such energy vectors if you take nuclear and fossil baseload out of the equation) so that's where advanced SMR nuclear can complement the low carbon mix. Hydrogen will be a VERY important energy vector for "hard to electrify" sectors next decade, BUT its high future production demand will add on the loading for solar and wind and so it potentially will not act as the baseload relief as one might think. The other possibility is biomass derived pyrolysis oils (and other "bio-crudes") but this is far too expensive at the moment and will probably continue to be so unless some standardisation & trading measures are agreed on - and then it will probably be gobbled up by refineries looking to decarbonise from fossil crude oil to supply the residual petrochemical, internal combustion engine and jet mix demand.
 
Is there much (or any) current research into alternative methods of electricity transmission?

When I was 8 years old I found a book in my school library on Tesla's work in this field. It fascinated me, and resulted in many schoolboy experiments with electricity. In retrospect it was lucky I didn't electrocute myself or burn down the family home.

It's always sunny or windy somewhere in the world...

I once read a magazine article (maybe in colors magazine?) about a guy who was part of a big experiment to achieve cold fusion, I think it was in the 80s. He was sure they nearly cracked it, and determined to make it happen. He set up a home lab somewhere in the Californian redwoods to continue his experiments. He might still be at it.
 
I think Rana above has responded better than I could have. Improved new designs are addressing the issue you raise, in theory fission can be made very cost-effective.

I'm glad that fission is not completely dismissed by most here. I do believe we should use it more than we have in the past.

DV's Solar capture with Hydrogen storage has got me thinking, I wonder if solar panel tech is robust and long lived enough to be viable...I see that Morroco (contains lots of the Sahara) maybe selling us solar power in the future.

As for power transmission... Wires!
 
I'd recommend you do a bit more reading on the subject.

I recommend that you watch the video and do some very simple maths. Current actual efficiencies (Q total)are around 10% (0.1). Based on current steam turbine efficiencies, you could hope to recover around 50% of the heat generated as electrical power. VERY, very simple maths indeed - 20-fold increase in efficiency to break even.

20-fold increase in efficiency due to scale-up alone!! Just to break even?

To get 50% more out than goes in would require an increase in efficiency of 30-fold. Even a 10% gain would require a 22-fold increase.

Fantasy
 
As for power transmission... Wires!

They work fine for short distances but the voltage required to efficiently export power from Australia to the UK over copper would make things tricky.

Yes, fission plants may well get cheaper in the future. As long as people need to fuel them, service turbines etc and store the waste though, it's going to be difficult to compete with solar which plummeted 85% 2010-2020 and continues to fall.
 


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