A discussion on fusion future. - A 'gentle' primer.

Reflections on fusion history, current events, and predictions for the 'fusion powered future.
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Chris Bradley
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A discussion on fusion future. - A 'gentle' primer.

Post by Chris Bradley »

Nothing new here, but I liked the gentle, non-partisan discussion into the topic which might be illumination to 'new-comers' to 'the biz':

http://physics.ucsd.edu/do-the-math/201 ... ar-fusion/

I liked that he put forward that working fusion-tech would be 'the "arrival" of the human species'; without it there is a pretty clear maximum time-line for technologically based mankind's survival, and it ain't that long!!

I also like that he reflects on one simple, rather obvious, fact - no-one, ever, has taken so long to figure something out and, even, take so long about it! Does that mean it *isn't* 'doable', or does it simply highlight that we've never crunched through such a difficult challenge before? Of course, it means neither, but what it does mean is that no-one can claim any real authority about fusion power's future, in any way... we're on uncharted ground, not simply because of the difficulty of the technology, but because no challenge has ever found mankind so wanting in the same way before.

Embedded in that challenge are not only technical ones, but political and cultural ones too.


>>>

"Fusion Prospects

"No one can truly say whether we will achieve fusion in a way that is commercially practical. If teams of PhDs have spent over 60 years wailing on the problem while spending tens of billions of dollars, I think it’s safe to use our fusion quest as the definition of hard. It’s a much larger challenge than sending men to the Moon. We have no historical precedent for an arduous technological problem on this scale that ultimately succeeded to become a ho-hum commercial reality. But for that matter, I don’t think we have any precedent for something on this scale that has failed. In short, we’re out of our depths and can’t be cocky about predictions in either direction."
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by kcdodd »

I don't really agree that there is a time limit for technology (well, short of universal heat death), or, even if that were true, that technologically based fusion would extend it indefinitely. Not to knock fusion, I just don't want to oversell it.
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Chris Bradley
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by Chris Bradley »

Unfortunately, many others don't agree either. I think [IMHO, and with due regard to your own opinion] that is a myopic view of human's future.

The problem is that it is unclear where the next 300 years of energy is going to come from, let alone the next 10,000 years. People don't even begin to contemplate 1,000,000 years future!

I'm not saying there aren't other options that may come along, but whatever it is, it is a world that doesn't look like the one today, especially population-wise, unless we can sustain equally high energy-density sources as we have now.

I'm lead to believe over 50% of the world's population now reside in urban areas. I don't see that this is at all sustainable without very high density power sources, such as fossil-fuel, or fission, powered stations.

If there is any sort of financial, climatic and/or conflict-based interruptions to the industrial infrastructure, I have to wonder whether that will be a very sudden end to what we think of as a modern life, because it just doesn't seem possible to me to re-manufacture, e.g., an oil-rig without an initial input of energy to do it, and without the oil-rigs we'd not be able to drill down 5 miles under the sea where the oil is these days. It was easy when humans started down this route of burning fossil fuels because the stuff was just laying there in pools on the surface! Imagine that over again, and we didn't have that to start with. How far would we have got if all the oil had been 5 miles under the seabed?

I'm no green hand-wringer environmentalist, this is just about plain adding up potential energy sources versus future demands. I can't see it balancing with what we have on the table at the moment that might deal with the issue. The old adage that humans will 'always find a solution' is demonstrably countered by the very act of fusion research itself. Yes, someone always seem to have found a way forward before, but it is an act of faith that 'someone' will come up with an alternative solution to high power density/quantity sources.

A key point of the article I am in full agreement with is the point that we're in a place we've never been before. We can't run this one into the future based on 'opinions', so future planning has to be based on objectively known extant power sources. Do we have enough for the future? I don't see it.
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by Richard Hull »

I'm with Chris on this one. With current needs figured and advanced on population growth, especially in Urban areas, we just do not have future energy resources to continue on the current path.

At HEAS we had a fellow speak on future energy issues. At the end of his talk he wanted us, his fusion segmented audience, to advance a possible real solution to energy issues as they stand right now which might stave off the malthusian end of energy resources. Coldly, I replied, rapidly get rid of 2+ billion or more living people. The solution seems obvious on a coldly scientific basis and would immedaitely relieve energy concerns. Unfortunately, the process of implementing the rapid kill off of approximately half the planet's population would demand a massive upset of the entire system, politically and economically. That 2 billion wouldn't go willingly. It would take a global nuclear war, followed by a pandemic of epic proportions and scale would have to ensue.

The absolute fragility of our technological society in the face of any major upset or several co-jointly occurring minor glitches is something that the common public cannot begin to conceive of nor wish to hear of or debate. They want circus.

Musing over the future is best left to the mystics. The future will certainly look nothing like we know of modern living today.

Richard Hull
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Fusion is the energy of the future....and it always will be
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by kcdodd »

I think the only truly sustainable energy source would ultimately derive from collecting solar energy. I can't remember the source atm, but I have heard that when the total area of nuclear power stations is taken into account, the buffer zones etc, that solar power could actually deliver just as much power. If we are going to concentrate in cities and destroy all vegetation anyway, covering it all in solar panels seems reasonable to me.

My point with fusion is that you still need a source of tritium: you need lithium. Granted, there is a lot of lithium. Enough to last maybe a million of years, I'm not sure (the iter website says 1000yrs from known sources). And a million years, or even a thousand, is way better than 50 years. But it would still run out long before the sun dies. I would guess that the actual *need* for fusion technology will be in space, once you get too far out, or if it's just not practical to use solar.
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by Frank Sanns »

Carter,

I am with you entirely. All of the fossil fuels that we use to supply 90% of the world energy is from the sun. Chemical batteries that have stored up the energy of millions of year only to be used up by man in just a couple of centuries.

I am not a big fan of nuclear power even though I realize that it has to be part of the long term equation. Near real time renewables with efficiencies that make sense is where our power needs to start coming from for long term success. Equal or perhaps even more important is energy conservation and appliance efficiencies. It does not mean a change in lifestyle, it means a smarter lifestyle. In fact, the first step in going solar is using all energy efficient devices as it is far less expensive to replace a 20 year old energy hog refrigerator with a high efficiency one than buying an extra half dozen solar panels to run it.

For sure the nuclear people and the non solar people are going to trash my post as they always do but having lived solar since 1998 with no compromises, I am fully behind it and would recommend it.

Frank Sanns
Achiever's madness; when enough is still not enough. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS
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Chris Bradley
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by Chris Bradley »

Solar is a lovely idea and it can, and does indeed, work on a small scale for low-density populations.

But take a look at, e.g., the UK. I've analysed the electrical and vehicular energy consumptions in the UK at present and figured that we, here, need around 1 GW per 100,000~150,000 people. That's basically a new GW (or three) power station that needs to be built next to every medium sized town in the country because the current ~100GWe installed capacity is only enough for around 15~20% of the population if you take into account road transport too.

Now convert that 100GWe to renewables and solar, and all of a sudden every town in the country needs an additional 10,000 acres (40km^2) to install solar farms 4 times as big as the current biggest solar farm in the world (at 250MW, which tales up 2,400 acres(10 km^2)).

Work that out in solar power, and all of a sudden it is impossible. We just don't have the space.

OK, so why not site 6,000,000 acres of solar panels in the Sahara to generate all the power the UK would need to replace its 100GWe and transport fossil fuel consumption. Are you serious?!!! Who is gonna clear that lot off after a dust storm. And besides, what sort of national security does that give us if any unstable country along the route merely has to throw a switch to hold the whole country in jeopardy.

The engineering involved in building and managing a solar farm that is the size of a 160 km square can be looked upon either as 'do-able' (bit-by-bit) or you might equally say 'never been done before on that scale'. Solar on that scale is, simply, unproven as viable.

I guess the idea then would be that Germany's Sahara solar farm will be a bit bigger, and all the other countries in Europe and Africa will then proceed to fill up the whole of the Sahara with their own 'stakes'. I can't see territorial rights issues throwing up any political issues there, then! [/sarc]

Maybe we can get by with solar ... providing Richard's 'solution' above somehow materialises (and on a slightly bigger scale). However, my main concern with that particular scenario is that whatever prompts that 'solution' will also be a cause of the decimation, and ultimately cause the fatal disruption of, any viable industrial infrastructure that can carry on building solar panels or whathaveyou.

In the US, you might actually manage it with solar, with the clean air of the large high desert plains of the 4 corner states. That's pretty unique. Maybe it could be made to work out in a few other countries too, but not for most.

Fortress America! Wahey! The US better start building that billion acre solar farm before the rest of the world's industrial infrastructure collapses!
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by Chris Bradley »

Carter Dodd wrote:
> I can't remember the source atm, but I have heard that when the total area of nuclear power stations is taken into account, the buffer zones etc, that solar power could actually deliver just as much power.

I've done a quick search and can't find anything that backs this up.

I put the following slide together with what I came across, by way of comparison.

...
Attachments
nuclear_susquehanna_versus_sarnia_ontario_pv.jpg
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by Frank Sanns »

Chris,

No land is needed. Photovoltaics and thermal solar are installed on the roofs of existing houses and buildings. Energy is generated onsite so there are no transmission loses and by spreading them out everywhere, security is the finest it can be. For larger generation, there are huge areas along the easements of major highways that is now just left unused.

Transportation is THE most inefficient use of energy on the planet right now as a whole. While this is bad for now, it is the number one place for major efficiency and better ways to move people improvements for the coming years.

You do not need to think out of the box for these solutions, You just need to quit listening to people who learned energy management when energy was so cheap that it didn't matter. They are the ones with the blinders on.

Frank Sanns
Achiever's madness; when enough is still not enough. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by Chris Bradley »

There are arguments for and against. Again, it can be countered that there just isn't this sort of land available in high density cities. Have you seen our terraced houses!! How can a block of flats have a foot print big enough to generate enough for all tenants, or a factory to drive its machinery? Houses are packed all together like rabbit hutches, and right up to the roads.

We run diesel cars that are hitting nearly 50% thermal efficiency, about their theoretical limit. There are hydrogen fuel cells that can hit 60% but then you have the losses in generation and storage that makes them much the same. EV/Battery cars are still very intensive in fuel consumption when they are made.

Whatever the 'arguments', the reality is 'The Reality', which is that there is scant evidence this is possible. It'd be the biggest gamble of humanity to presume we'll be able to run smoothly from fossil fuels straight to solar. I'm not saying it is impossible, but we really have never been in this position before and if that transition doesn't go to plan, then that'll be that if there are no 'fall-back' plans already proven and in place.
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by kcdodd »

Im not sure, maybe I made it up. Its kind of besides the point though. Going with a 1000yr power supply with fusion or fission because we see it as more economical then solar only means we bought another 1000yrs to figure out how to make solar economical.
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by Steven Sesselmann »

Hi Guys,

I have been following this post in the background, and it is clear that the world faces a problem, what is even more clear is that most people think it is merely a temporary issue and that someone will soon fix it. Companies are investing in growth and prosperity will return, I see no less than 5 building cranes on the horizon, building office towers with lifts and air-conditioning systems, and those pretty windows that can't be opened, because it makes more sense to pump cold air through the building than to open the window...doh!

In the office next to mine, resides a consulting company, who are busy advising the Sydney Airport Corporation on how to improve the airport for increased capacity.....

Okay, a small group of informed people are beginning to ask where will it end, but what if anything is being done about it?

Not much at the moment, but if we re-engineered our world, and used the remaining resources to rebuild the obsolete infrastructure, we might stand a chance.

With communication through the internet, change can happen fast, so we need to reserve enough energy to run the internet, fortunately with the fiber optic roll out around the world, and more efficient processors, the net will consume a little less.

People need to live close to where they work, walk or ride a bike, offices need fresh air ventilation, go back to using fans and natural draft to ventilate in hot countries, cold countries need to redesign buildings to take advantage of light and build on the sunny side of the hill, animals have known this all along.

Grow food where people live, If you are a Golfer, I apologise in advance, but you simply can't have all that fertile irrigated land, just for walking around in funny pants hitting a 1" ball, this land, usually located in urban areas, can easily be turned into food growing areas.

Business people, don't need to fly all over the place to do business, try having virtual meetings using Skype or similar technology, it works and it will dramatically reduce your costs.

Solar energy is available now, and in Australia at least the average home can supply around 7kWh per day, just about enough for home consumption, but not enough for industry.

So we have a problem, too many people, with no way to access the energy required to feed them.

To conclude, I link to a recent page by Paul Chefurka, where he talks about the 5 stages of awareness, and how he believes 90% of the worlds population is in stage 1.

http://www.paulchefurka.ca/LadderOfAwareness.html

Steven
http://www.gammaspectacular.com - Gamma Spectrometry Systems
https://www.researchgate.net/profile/Steven_Sesselmann - Various papers and patents on RG
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by Frank Sanns »

High density cities are the most efficient. The most energy efficient structure for heating and cooling is a cube because it gives the greatest volume for a given surface area. Bigger cubes are even better so those high density living spaces are great. For solar living in a mega cube, 15 m^2 to 20 m^2 is sufficient for a family of 4 to have virtually unlimited energy available for all but the most hungry of appliances. It also puts the workers and families closer together thus requiring no cars. This is a typical feature in big cities where a car is not an asset but a costly liability.

In many of the world's largest cities, cars are already being eliminated by legislation. Often certain license plates can enter the city on certain days and not on others. Park and rides outside of the city with high efficiency rail predominates. The least energy efficient living space by far is a single family home. It uses the most energy and the materials to build. It also requires a car to commute to the store and to work and often it is significant distances on roads with no traffic light control strategy so it is stop and go. The future is here in some places of the world but unfortunately not in most.

Frank Sanns
Achiever's madness; when enough is still not enough. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by Chris Bradley »

Frank, I'd need to see the figures. I just went looking for evidence that this is sustainable and can't find it. One paper ("Assessment of photovoltaic potential in urban areas using open-source solar radiation tools", Hofierka) suggests meeting 2/3rds of electricity needs with solar, but that's not counting heating (a town in Slovakia was used for the study). And that's only a numerical analysis, I'd like to see the practical infrastructure difficulties too of having that much installed capacity.

It's winter here in UK. There's not even enough ambient sunlight to melt the ice on my car all day long if there is cloud cover at the moment (and it's only getting down to zero C, not much lower than that), and we're still a month or two away from the coldest parts of winter! So what chance is there to heat my house all day-and-night long, let alone power it with electricity?

And that's long before dealing with the energy supply to the trucks that have borought me all my provisions from outside my town, and running the factories that have processed and made the stuff.

Show me the numbers. Really, I'd like to see some evidence this is possible so I do not ignorantly blunder my way through life not realising solar is a global energy solution that exists already. From where I am sitting, running the world off of solar panels on rooftops does not look feasible. I'll agree that solar is a work-in-progress, works in some installations very well, and can provide a 'boost' in others. But to cover a wider scope and industrial scale, high-density power sources will still be required and it's the same argument then as other 'renewables' - if we have a base load of power stations that 'underwrites' solar when it's cloudy and cold and demand exceeds installed capacity, then why not use the base load all the time (that is to say, because it will have to be nuclear in the long run, so just leave it running!)?

We need to save our stocks of fossil fuels right, and immediately, now and not hang about hoping mankind will become magically more efficient over night so solar will be sufficient to meet needs. We need to start moving to 100% fast breeders *now*!!!! If it transpires over time that solar is sufficient, then we can turn them off, Great!, and give up funding fusion research (maybe!). If it transpires solar is not sufficient, we have the base-load sorted without fear of energy shortage for a few thousand years, and a plan to get fusion going still for the rest of human life on Earth, and maybe beyond?

I think I've exhausted any points I'd want to make on this subject, except to remind mankind about putting too many eggs in too few baskets!!
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by Frank Sanns »

Chris,

Solar voltaics will only be a part of the solution as you say but here are some hard facts and numbers for just that.

Photovoltaic panels do not work only from direct sunlight. They work on photons. If it is light outside, then they work albeit at a reduced capacity. This reduced capacity is also factored in with the seasonal length of day calculations. Maps are produced for the locations of the world that figure in all of this data. They are called solar insolation maps. This map will show the number of hours of equivalent sunshine year round. For where I live in Pittsburgh, PA, the second most cloudy city in the USA, the number of equivalent hours of sunlight year round is 4.5 hours.

This 4.5 hours number means that 1 kw of photovoltaic panels produce for on average, 4,5 hours per day. So 1 kw of panels will produce 4.5 kilo watt hours of power for the day. This is very close to my actual yearly numbers of power production per kw of panels. I happen to have just under 3 kw of solar panels and I made around 4 MWh of electricity so far this year. With the short days for the next 60 days, I am at my production lows for the year for clouds and short days plus my panels get some shadows since the sun is only maximums at 26 degrees above the horizon now at noon. Still it is impressive that I am making on average, a quarter that I am making on a summer's day. Cooler temperatures (better panel efficiency) and clearer winter skies help.

I am connected to the grid so for all but the shortest days of the year, I put excess power into the grid during the day when the demand is the greatest, then I use some of it back at night. Right now this is great because coal fired plants take many hours or days to change power levels and if there is capacity for the day, it then is wasted into the night. Not good for fossil fuel consumption or for the extra pollution that that creates.

Again, just sticking with photovoltaics for this discussion, the question becomes how to manage it longer term. Without going 100 or 200 years, the transition in the US might look like a mix of solar, coal, and natural gas and nuclear and any other sources. Not in any particular order. The nice thing about solar is it is predictable to a significant extent by the weather. If a period of rainy days are coming, it is clear that other sources will have to pick up the slack. It is also clear that on partly cloudy days, a large region will still have a stable energy output as some panels will be in sun while others will be partly shaded. The big swings in solar output on a partly cloudy day when the panels are spread out, is a non issue yet I hear detractors crying this all of the time.

Coal then since it has the longest ramp up and ramp down time is the one that is given the majority of the base load. The load that it can do day after day with no changes so it is running maximum efficiency with as little waste as possible. Add in the nuclear to the capacity that is available and then make up the daily changes with a quick response natural gas plant coupled with the somewhat adjustable nuclear plants (or hydoelectrics or whatever the best adjustable local energy source is) and you have an energy management system. Energy management is already in place for the grid as power companies spend big bucks on systems that will tell them the predicted use of power on any given day of the year along with any other conditions like heating days, big sports days, holidays, etc.. They already do not want to waste their coal and other sources as it is $$$ off of their profits. Solar and all other contributing energy sources will be quickly absorbed into their models.

I tried to stay focused only on solar but this post could have turned into a White Paper on energy as a whole but I hope it conveyed more specifics about PV.

Frank Sanns
Achiever's madness; when enough is still not enough. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by Richard Hull »

I think future energy is really more related to human community, technological survival and geo-political issues than some form of new, old or renewable forms of supply. I fear that if the worst happens, solar, hydro and fossil will be the types of surviving real resorces in a post apocolyptic, greatly de-populated world.

If the above is realized, fusion will never be conquered on a time scale that is worth discussion and even fission would lapse for a century or more into that future, if ever to return at all.

Small localized communities with hyper-limited, rationed supplies of electrical and steam energy living in a useful but simpler world circa 1900, but with radio and perhaps even TV and what remains of computing power. Some here might rather die than live in such a world. Others here might welcome it.

Again, the fragility of our society's technology coupled with its tenuous and often strained supply chain to a vast population will certainly be the achille's heel and the ultimate snare to our feet. It wouldn't take much to upset the apple cart, big time.

There is no crystal ball in any of this.

The Boy Scout motto "be prepared" is sage, but the world, as a whole, isn't having any of it. So the motto returns to its original origin, the individual mandate involving accrued skill sets and a sense of purposeful doing.

Richard Hull
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Fusion is the energy of the future....and it always will be
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by Jim Kovalchick »

By the time that fusion technology is developed to the point that it can be a practical energy source, we will also have the ability to get fusion fuel from off earth. He3 is an excellent fusion fuel and it exists in abundance on the moon.

Also, favorably comparing solar power collection to nuclear fission stations is silly. My plant still runs when it snows and at night. I'm not anti solar, and if I had a few extra bucks I would allow government subsidies to install some cells on my roof. But even with subsidies, the investment cost won't pay back my investment for well beyond the amount of time I plan to own my home. If I thought I could transfer the cost to the buyer when I sold (which won't happen) then okay. Even solar has a NIMBY and negative environmental aspect. Again, not trying to knock solar, but it certainly is no reason to abandon a drive to a clincher energy source such as fusion.
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by kcdodd »

Im not convinced helium 3 fusion is good for energy production, especially if you are talking about having to harvest it from the moon and bring it back. Its really only good for decreasing the neutronicity. My own estimates indicate a reactor at 10-15% neutronicity might be possible with a he3 mix. But the best possible Q of such a reactor is not good. Like 5, definitly less than 10. Power density is not good either. I would only consider it for special applications, like a fusion rocket or something.

Playing this game of economics and fusion versus solar is kind of silly since we don't know how much fusion would cost. If you use iter as a baseline, that would put it at like $60/watt. You would have to convince me that in the time it takes to build fusion power plants, that solar power wont still be the cheaper option per watt anyway. Especially if you want it to be he3. You would have to assume that the cost of solar would decrease way slower than the cost of fusion would.
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by Chris Bradley »

Jim Kovalchick wrote:
> He3 is an excellent fusion fuel and it exists in abundance on the moon.
'Abundance' is rather relative. It is no more than about 3 times more concentrated in lunar He than it is in terrestrial He. Hardly worth going to the Moon for; see - viewtopic.php?f=22&t=8445#p58648 .

I don't know where this tall tale came from. Someone clearly wanted to try to make a non-existent case to go to the Moon sound plausible, I guess.

At the moment, 'excellent fusion fuel' is a bit misleading too. Sorry.
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by Jim Kovalchick »

Chris,
I stand by my statement that He 3 would make an excellent fusion fuel and I am not alone in thinking that. The use of the word 'excellent' is subjective enough that I feel safe in using it because how it's measured is my choice. Helium 3 will be harder to fuse than the hydrogen isotopes, but once we figure out how fusion can be managed as a real fuel supply I think that the choice of fuel won't seem as limiting. What is already true is that He 3 is much easier to handle than tritium which is radioactive and a nuisance pollutant. The neutron dynamics seem to be intriguing as well.

It's all fancy right now, but its never too early to look to the future.

http://www.msnbc.msn.com/id/26179944/ns ... er-future/

Jim K
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by Chris Bradley »

The news article is simply a demonstration of repeating the tall-tale.

Seriously, which do you think would be easier - extracting 1 part in 3,000 from lunar He on the moon, or extracting one part in 10,000 from terrestrial He whilst here on Earth?

In regards 3He being 'excellent', the fusion reactivity curve is lower even than the DD reaction at anything much below 100keV. Tritium handling is not an issue going in to the reactor for DT, but is an issue for retention and management within the chamber. Unfortunately, D+3He does not relieve that problem because the DD reactions will produce tritium too, so the same problem will exist. To what extent I don't know. The only way to beat that entirely (and the neutrons from DD) is to run 3He+3He, but you need MeV's for that.

It's just a bit hopeless to talk about these reactions being useful at the moment while DT still can't be made to work, which is an order of magnitude easier than any other reactions.
ab0032
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Real name: Alexander Biersack

Re: A discussion on fusion future. - A 'gentle' primer.

Post by ab0032 »

I disagree, even without fusion we have enough Uranium to get by for one billion years at todays energy consumption levels, if we breed, that would last 100 billion years supply of todays energy use.

Of course energy consumption will continue to rise at 3% per year as it has done in the past 150 years. Uranium can be derived from unconventional sources such as ocean water, and the price really does not make a difference.

Also it is no problem to develop thorium reactors, either molten salt or other within a few years and thorium is even more abundant.

So today already we have energy security for a very long time. Energy is abundant. Only anti-humanist environmentalists are preventing that we access the cleanest and safest of all known energy sources.

And I see no reason, why humanity should not be able to access source on mars, moons of jupiter or elsewhere, if we would really come to a crunch.
ab0032
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by ab0032 »

Solar power first needs a large initial energy and resource investment. We dont have these resources now and it would be silly to do it. Solar collectors in deserts also pose a major challenge, with dust and storms.

But the main point is that solar is such a diluted form of energy, that all deserts of the world would not suffice to supply a demand growing at 3% by 2070 or 2080. So solar is just a short bridge to nowhere.

Anyone could do the math on the back of an envelop. It doesnt add up.
ab0032
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by ab0032 »

Why dont you give a reason, why you oppose nuclear? It has the lowest number of deaths of all energy forms, even better than PV and Wind. It is also the cleanest.

Is it just an emotional thing? Does it feel better to live in the mainstream media mindset, than forming an own opinion that digresses from the greenpeace propaganda, which is preventing a clean solution for much to long now and has kept us locked in a coal and oil world?
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Chris Bradley
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Re: A discussion on fusion future. - A 'gentle' primer.

Post by Chris Bradley »

Alexander Biersack wrote:
> ...we have enough Uranium to get by for one billion years at todays energy consumption levels, if we breed, that would last 100 billion years supply of todays energy use.

Not sure that is true. Do you have figures for this claim?

According to the IAEA study there is surprisingly little - about 50 years worth of current stocks and 'immediate' reserves if burnt in slow reactors, which I understood should mean multiplying up to 5~10,000 years, at current consumption, in fast breeders, from known/predicted reserves.

The more I think about this, the more I realise why people get excited about developing thorium. Seems to hit a lot of the right buttons. Maybe fusion will never get to 'over unity' but if it works as a half-decent neutron source, then maybe the future is by activating Thorium to make it fissile? Maybe Rubbia's 'energy amplifier' will have its day after all... but even that will probably only last a few 100,000 years.

Following text from "ANALYSIS OF URANIUM SUPPLY TO 2050" ;
http://www-pub.iaea.org/MTCD/publicatio ... 04_scr.pdf


""
ANALYSIS OF CUMULATIVE SUPPLY
AND DEMAND TO 2050
The adequacy of resources to meet demand is
measured in two ways. The first measure is a direct
comparison of resources at different confidence levels with
market based production requirements. The second
measure takes into account the fact that not all resources
will be utilized within the study period by comparing
projected production with requirements. The importance
of the difference between the two ways of measuring
resource adequacy is indicated for the middle and high
demand cases in Table II.
Production from high confidence RAR is projected to
be adequate to meet all requirements in the low demand
case. Therefore, deficits are not projected to be a factor in
the low demand case. As we progress to the middle
demand case, relatively high confidence known resources
fall short of market based production requirements by only
146 000 t U, or by less than the annual demand in each
year from 2041 to 2050. With the addition of lower confidence (undiscovered) EAR-II, resources actually exceed
requirements by about 2 million t U. However, a combination of timing when production centres will be cost
justified and the size of their resource base precludes full
utilization of resources, resulting in a projected shortfall of
844 500 t U between production from known resources
and market based production requirements.
""
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