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Posted

While I totally agree with the points that have been made, about the REAL performance of the current crop of fusion devices, I think that there is actually great cause for optimism.

Firstly, the gains in performance of fusion in the last fifty years have been enormous. If you take as your yardstick the values of Q achieved, and the duration of maintained plasma, the measured progress has outstripped the progress in computing. And right now, with the building of ITER, we are building a machine that is almost there, in terms of being able to power itself and give off surplus electricity. The projected Q values only need to be doubled, at the most. When you consider that current values are hundreds of times better than what was achieved a few decades ago, then doubling the performance of ITER is not asking a lot. I would say that it’s a dead cert bet that we will get there, it’s more a question of when.

On the subject of when, there’s a big new bit of technology lurking in the wings, that will give a boost to virtually any magnetic confinement reactor, and that is the recent progress in the field of high temperature superconductors.

They are testing them out at the MIT fusion facility, and the improvement in magnetic field figures is enormous, so dramatic that it looks like being a game changer. The ITER superconductors are cryogenic, and have to be kept extremely cold. You can only go so far with them, because over certain levels of magnetic field, they stop superconducting. So they impose a limit on the field that you can create. The new REBCO superconductors being tested at MIT have experimentally given double the magnetic field that equivalent super-cooled superconductors could achieve. And double the magnetic field, for engineering reasons, allows a reactor to be one tenth of the volume for the same output.

The thing about Tokamaks is that what limits the output is not the availability of fuel. It’s the stability of the plasma. For a given size of plasma, when you increase the fuel input, instead of getting more power out, you get disrupted unstable plasma, which is the limiting factor. Various methods are being researched of achieving stable plasma at higher powers. The main one being employed at ITER is the massive increase in overall size, and that’s what’s cost all the money and all of the time. It was thought that with superconductors having a limit on the field strength, size was the most promising way to go, to achieve more stability and denser plasmas.

With the rapid development in the REBCO field, it looks like the limits are off on field strength, or will be in the near future, so stable plasmas will be feasible at much higher power levels, in smaller reactors.

The ITER project is wedded to the superconductors that are already in the pipeline. But I think that it’s highly likely that once the project has been run, and the lessons learned re tritium breeding and blanket materials, and neutron shielding and remote handling, etc etc, there will be a redesign involving REBCO  superconductors, and that will boost it well past the REAL break-even point, of net electricity power output.

This is the wikpedia  page about the REBCO superconductors, :

 https://en.wikipedia.org/wiki/Rare-earth_barium_copper_oxide 

And here is a link to an extensive MIT presentation, about what they have done and are planning, using this technology. I whizzed through the introductions, but the meat of it is very interesting and encouraging :

https://www.youtube.com/watch?v=KkpqA8yG9T4&t=2078s  

Posted
1 hour ago, mistermack said:

And right now, with the building of ITER, we are building a machine that is almost there, in terms of being able to power itself and give off surplus electricity. 

Define “almost there” and provide evidence of this claim, please.

Considering that ITER is not designed to generate any electricity.

https://www.iter.org/proj/inafewlines

ITER will not capture the energy it produces as electricity

Posted
45 minutes ago, swansont said:

Define “almost there” and provide evidence of this claim, please.

There being a point where the reactor can produce enough heat to create all of the electricity needed to power it, with preferably some kind of surplus. 

From the wikipedia page on ITER

ITER's thermonuclear fusion reactor will use over 300MW of electrical power to cause the plasma to absorb 50 MW of thermal power, creating 500 MW of heat from fusion for periods of 400 to 600 seconds.[10     

Just on it's own, 500 MW of heat should be able to produce maybe 250 MW of electrical power, when harnessed through steam turbines. So if that was fed back in, the input of electrical power would have a deficit of 50 MW. In other words, ITER would be getting close to powering itself. 

However, in those circumstances the reactor will actually be putting out 800 MW of heat, as you will have most of the heat that you put in, on top of the 500 MW from fusion. You should be able to easily generate in excess of 300 MW of electrical power from 800 MW of heat. 

When you look at the timeline of fusion power, a situation as above is "almost there" bearing in mind how far they have come.

1 hour ago, swansont said:

Considering that ITER is not designed to generate any electricity.

So what ?                           

Posted
9 minutes ago, mistermack said:

So what ? 

So you can’t make any claims about how much electricity ITER will produce. It will be zero.

Any claims about what ITER will do have to be taken with a grain of salt. Those are goals. Complex experiments rarely work as planned.

As we saw in the other thread, producing more heat than you put in is not the same thing as self-sustaining.

 

18 minutes ago, mistermack said:

Just on it's own, 500 MW of heat should be able to produce maybe 250 MW of electrical power,

Why? Because you say so? Do any of the designs predict this?

Once ITER has demonstrated what it needs to, you have to fund, finish designing and then build the next one. The EU DEMO, the next step, is scheduled to take decades before it’s up and running. (estimated in the 2050s, assuming everything goes right. IOW, this is not imminent)

EU DEMO is being designed to produce 2 GW thermal and 750 MW electrical. So less than half of the thermal output.

https://en.wikipedia.org/wiki/DEMOnstration_Power_Plant

Posted
25 minutes ago, swansont said:

So you can’t make any claims about how much electricity ITER will produce. It will be zero.

You're just being ridiculous. I didn't make any claim whatsoever of what ITER WILL produce. I gave my estimate of what it's potential was. As you must surely very well know. You are nitpicking to a hilarious extent. 

 

32 minutes ago, swansont said:

Why? Because you say so? Do any of the designs predict this?

You are talking as if electricity from heat is some new untried phenomenon. It's done in every thermal power station in the world, and was first done by steam turbine in 1884. Really, I can't take this line of argument seriously. 

Posted
12 hours ago, mistermack said:

You're just being ridiculous. I didn't make any claim whatsoever of what ITER WILL produce. I gave my estimate of what it's potential was. As you must surely very well know. You are nitpicking to a hilarious extent. 

 

“with the building of ITER, we are building a machine that is almost there, in terms of being able to power itself and give off surplus electricity”

The point is that ITER won’t produce electricity. It will be unable to do so. That will have to wait until the next device, which isn’t slated to be online for ~30 year…if there are no schedule slips for any reason.

We aren’t “almost there.” We’re at least 30 years away, which has been the state of fusion for >50 years.

 

12 hours ago, mistermack said:

You are talking as if electricity from heat is some new untried phenomenon. It's done in every thermal power station in the world, and was first done by steam turbine in 1884. Really, I can't take this line of argument seriously. 

No, you’ve missed the point. The problem is getting fusion to work at this scale. You’re just assuming things will go as planned and on schedule, which hasn’t been the state of affairs for pretty much the whole history of fusion efforts.

 

edit to add:

https://www.science.org/content/article/iter-fusion-project-take-least-6-years-longer-planned

"The project was officially begun in 2006 with an estimated cost of €5 billion and date for the beginning of operations—or first plasma—in 2016."

Now the estimate is first plasma in late 2025, according to the Wikipedia article. And the issue of cost overruns and who will pony up cash for an engineering prototype when that well runs dry is a separate problem. 

 

Posted

One thing I haven't see in any of the articles on ITER or DEMO is where all of the input electrical power is going. 

The figures for ITER are 300 MW electrical input, with only 50 MW heating power going into the plasma. It would be interesting to know where the 250 MW is being used. Is it because most burns will be short duration, so a lot of energy will be used up getting the system up to operating conditions? The magnet coils will obviously use power, but will it be on this huge sort of scale? If it is, it will need a hell of a lot of cooling. 

Posted
12 hours ago, mistermack said:

One thing I haven't see in any of the articles on ITER or DEMO is where all of the input electrical power is going. 

The figures for ITER are 300 MW electrical input, with only 50 MW heating power going into the plasma. It would be interesting to know where the 250 MW is being used. Is it because most burns will be short duration, so a lot of energy will be used up getting the system up to operating conditions? The magnet coils will obviously use power, but will it be on this huge sort of scale? If it is, it will need a hell of a lot of cooling. 

There are 10 thousand tonnes of magnets in ITER and they are superconducting. I would imagine those are going to take a huge amount of electricity to run, both for the magnets  themselves and for the refrigeration systems. And then it is a big plant, with heating, lighting and ventilation requirements like anything else.  

Posted
On 12/28/2021 at 3:11 PM, exchemist said:

There are 10 thousand tonnes of magnets in ITER and they are superconducting. I would imagine those are going to take a huge amount of electricity to run, both for the magnets  themselves and for the refrigeration systems. And then it is a big plant, with heating, lighting and ventilation requirements like anything else.  

That's fair enough, but we are talking about a phenomenal amount of energy. I MW from a coal plant will be enough to supply 4,000 homes. So scale that up to 250 MW, and it is enough power for one million homes. 

I would like to see a breakdown of the power figures, and how much of it is incurred powering up and down, and how much is used during an actual plasma run. Also, how hot the cooling media is on exit, and whether it has the potential for adding to the electrical generation. 

Posted

It sound like if running continuously there would be waste heat equivalent to a coal or gas power plant. In addition to the cooling at the coal or gas plants or other sources of it's electricity. It doesn't run continuously.

The info around the cooling isn't prominent but (from Wikipedia, without much detail) it sounds like ITER has water based cooling, from a closed system joined to a separate cooling system via heat exchangers, with one conventional cooling tower plus cooling ponds. Water is piped in and discharges back to a major river. It wasn't clear if there is air cooling as well, like refrigerators and A/C might use.

Now, if only the waste heat could be harvested... but if it could do that effectively and efficiently we probably won't need fusion power plants.

Posted
1 hour ago, mistermack said:

That's fair enough, but we are talking about a phenomenal amount of energy. I MW from a coal plant will be enough to supply 4,000 homes. So scale that up to 250 MW, and it is enough power for one million homes. 

I would like to see a breakdown of the power figures, and how much of it is incurred powering up and down, and how much is used during an actual plasma run. Also, how hot the cooling media is on exit, and whether it has the potential for adding to the electrical generation. 

Yes you have a point. 300MW is the output of a decent sized power station.

Posted

While the criticisms of the ITER and DEMO project are fair enough, and widely repeated, it's worth putting them into context. 

Nuclear Fission plants have been around for many years now, but they still suffer from extreme delays and cost overruns, which match or are even worse than the fusion programs. 

Take the latest EPR station in Finland for example. Initial costs were to be 3.7 billion Euros, and it was to go online in 2009. The latest costs are well over 8 billion, and it will start generating in mid 2022. It's the inherent danger of fission, with it's added waste problems, that have made costs and timescales inflate so much. 

Fusion holds out the promise of costs and timescales coming down over time, not going up and up. Because safety is so much less of a concern, as is waste management. Fission plants should have got better and cheaper over time, with improved tech, but it didn't happen because of Chernobyl and Three Mile Island, and Fukishima. Also because the problem of waste was not properly taken into account at the outset. 

With a mature fusion industry, there is also no chance of out-of-control inflation of the price of it's fuel, as it should be self-sustaining in that regard once the production of tritium has been confirmed as a working technology. That is one of the main goals of ITER, as the world supply of tritium is very limited at present. 

There does seem to be a lot of investment going into fusion, in spite of the slow progress. The UK government have taken the decision to build a DEMO class spherical tokamak that will produce net electricity and have already allocated hundreds of millions for initial work and are looking for a suitable site. It's called STEP, it's wiki page is here https://en.wikipedia.org/wiki/Spherical_Tokamak_for_Energy_Production 

It's planned to be producing net electricity from fusion by 2140.  Other countries are making similar plans, as well as private enterprises working on slightly different fusion technologies, such as Magnetised Target Fusion, Canadian company General Fusion is to build and operate a plant to demonstrate its nuclear fusion technology at UKAEA's Culham Campus near Oxford in the UK. The Fusion Demonstration Plant (FDP) will pave the way for a commercial pilot plant using Magnetised Target Fusion (MTF) technology and is expected to begin operations in 2025."  

https://world-nuclear-news.org/Articles/Fusion-demonstration-plant-to-be-built-in-UK   

Just by the way, does anybody else think that there is a link between the Germans closing their nuclear power plants, and the spiralling price of gas in Europe? Surely no coincidence. And a signpost to future trends in energy prices.                         

Posted
1 hour ago, mistermack said:

With a mature fusion industry, there is also no chance of out-of-control inflation of the price of it's fuel,

Is this really an issue for any green energy production method?

Posted
6 hours ago, mistermack said:

Just by the way, does anybody else think that there is a link between the Germans closing their nuclear power plants, and the spiralling price of gas in Europe? Surely no coincidence. And a signpost to future trends in energy prices. 

You sure you want to derail the thread with a German nuclear vs renewables sidetrack?

In answer to the question, no, I think that is oversimplistic - it may play some part in short term demand driven volatility but there is too much else going on, including Russia playing games with supply availability.

How much German supply comes via long term contracts at fixed prices and how much is vulnerable to short term variability? How well did they anticipate Covid would impact economic activity - declines and rebounds - as well as anticipate how nuclear closures would affect demand? How well does Germany manage gas reserves?

Gas prices have been and are very volatile all around the world quite independently of German policy to phase out of nuclear - which is a tiny portion of global demand.

My hope is they will double down on renewables as a response to price volatility and gas market games as well as continue to push ahead with a transition away from fossil fuels, but I don't know how post-Merkel Germany will manage Energiewende into the longer term.

On the face of it, I would have favored keeping the nuclear plants for their working life, for the low emissions, but my understanding of the in's and out's of German energy and climate politics is limited. But I do think failure of large parts of German politics to fight for nuclear is down to the same kinds of apathy and hostility to strong climate policies we see everywhere - handing the issue to others in "you care so much, you fix it" style, whilst supporting coal and gas. "Not like that" isn't alternative policy.

So far the alarmist economic doomist fears of renewable energy have failed to eventuate although short term volatility still gets treated like evidence of fundamental failure. Germany is still the biggest and most successful industrial nation of Europe.

Posted
7 hours ago, swansont said:

Is this really an issue for any green energy production method?

Not so much for that 28% of the market. Apart from the price of Uranium fuel. And apart from the price of biofuels. And apart from the fact that green energy producers are also energy consumers like everyone else, and they have to pay market rates. 

1 hour ago, Ken Fabian said:

On the face of it, I would have favored keeping the nuclear plants for their working life, for the low emissions,

I think it's an incredibly stupid step to take. And with markets being driven by supply and demand, a small drop in supply can cause a much bigger hike in price, in the short and medium term. In the energy market, the demand is not so price sensitive as in other markets. People still need energy, whatever the price rises are.

Posted
9 hours ago, mistermack said:

Not so much for that 28% of the market. Apart from the price of Uranium fuel.

How expensive is uranium, though? $100/kg or thereabouts? How does that compare to the cost of the plant? Which is the primary driver of the cost of the electricity nuke plants produce.

Sun and wind are free. The cost of “green” energy is largely driven by infrastructure costs.

9 hours ago, mistermack said:

And apart from the fact that green energy producers are also energy consumers like everyone else, and they have to pay market rates. 

And that’s a problem?

 

Quote

And apart from the price of biofuels.

(Biofuels are the product, not the raw material)

 

Posted
2 hours ago, swansont said:

How expensive is uranium, though? $100/kg or thereabouts?

That's not fuel. It's the raw material for making the fuel. The cost of Uranium fuel is low, compared to overall costs. But not negligible.

 

2 hours ago, swansont said:

Sun and wind are free. The cost of “green” energy is largely driven by infrastructure costs.

 Nobody said otherwise. 

Posted
On 1/2/2022 at 3:30 PM, swansont said:

You implied it by bringing up fuel costs.

I implied that sun and wind are not free?? You seem to be reading between your own imaginary lines. 

On the subject of the cost of nuclear fission fuel, I would contend that the real cost has to include the cost of decommissioning it and storing it for as long as it's hazardous. And that portion of it's cost has inflated by a huge factor in the last fifty years. The actual market price of the raw material is depressed at present, because the demand has seriously dropped in the last twenty years. That's probably going to stay that way, but it could change, if the cost of fossil fuel spirals again. 

Posted
13 hours ago, mistermack said:

I implied that sun and wind are not free?? You seem to be reading between your own imaginary lines. 

If that's how you read it, I'm afraid I can't help.

 

13 hours ago, mistermack said:

On the subject of the cost of nuclear fission fuel, I would contend that the real cost has to include the cost of decommissioning it and storing it for as long as it's hazardous. And that portion of it's cost has inflated by a huge factor in the last fifty years.

True. And a non-sequitur. It's unrelated to my point. 

13 hours ago, mistermack said:

The actual market price of the raw material is depressed at present, because the demand has seriously dropped in the last twenty years. That's probably going to stay that way, but it could change, if the cost of fossil fuel spirals again. 

OK, so let's say the cost of uranium went up. What impact is that going to have on the cost of electricity from nuclear power?

 

https://atomicinsights.com/nuclear-energy-is-cheap-and-disruptive-controlling-the-initial-cost-of-nuclear-power-plants-is-a-solvable-problem/

The cost of the fuel when the report was written was about a half-cent per kwh, and "This cost is based upon the amortized costs associated with the purchasing of uranium, conversion, enrichment, and fabrication services along with storage and shipment costs, and inventory (including interest) charges less any expected salvage value."

So even if the raw uranium cost went way up, this will have a minimal effect on the overall cost of the electricity, since the processing costs would be fixed. 

The infrastructure is the main driver of cost

 

Posted
On 1/2/2022 at 12:32 PM, mistermack said:

I think it's an incredibly stupid step to take.

I don't think we can assume that if German Greens had just supported nuclear then EnergieWende and emissions reductions would be more successful and more advanced. We can decry the historic and ideological baggage that makes most Environmentalist orgs anti-nuclear and free market capitalists anti-climate action; both left nuclear hanging in the breeze just when the winds of change blew through. But I believe it was the latter that was pivotal; it wouldn't have been up to Greens except mainstream politics handed the issue, the podium, the microphone to them. I am cynical enough to think wind and solar got mainstream support over nuclear because they were expected to make no difference.

In an alt-history timeline Greens divided on nuclear may well have led to overall weaker action on climate and clean energy; certainly the German coal and gas interests would have taken advantage of internal disagreement, without supporting nuclear. Reduced early support for wind and solar - EnergieWende being a driving force for making them globally mainstream - could easily have been a consequence, leaving us all further behind at this point.

Greens expect longer term RE growth to displace the gas as well as the nuclear; I am not prepared to declare they were or are wrong to make RE their focus and distrust nuclear and the "just use nuclear" arguments. Germany is a major industrial nation and despite the economic alarmist fear of being economically ruined by RE, it has grown whilst significantly reducing both emissions intensity and total emissions. Even after nuclear closures (past the short term reverberations) Germany's economy has grown and emissions have gone down. The leadership has changed so we will need to see how they proceed.

To establish itself as a primary clean energy option nuclear now it needs those low cost, fast to build, ultra safe modular nuclear power plants - but they are decades overdue and look unlikely to ever be low cost - perhaps they are not so simple and easy and reliable and safe as the optimistic advocates like to make out.

I suggest that whilst support from "green" advocacy might help nuclear it isn't essential;  the essential support base nuclear absolutely has to have is still supporting fossil fuels and opposing the shift to clean energy. In any encounter with a nuclear supporter I put the odds above even that they will dispute the validity of climate science; with friends like that... Above even for the commenters at sites like atomicinsights.com - I suspect that thread of climate science denial running through nuclear advocacy is there in Germany too, despite appearances that climate science denial is not widespread there.

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