Energy From Thorium Discussion Forum

Actually it more and more clear that the more work and investment in fusion, the more expensive it's going to be. Reality is sinking in with more R&D, rather than the cost coming down.

Its not that there haven't been developments, or even some minor "breakthroughs" if you will.

Its that those developents are now clearly so expensive that fusion has become too expensive too matter.

Remember ITER is only starting to be constructed. Experience with other nuclear facilities is that they usually end up 50-150% more expensive when finished. So ITER may end up costing 30, 40, 50 billion before it actually works.

From https://en.wikipedia.org/wiki/Nuclear_fusion under "Neutronicity, confinement requirement, and power density", there is a table of fusion reactions. D-D requires 30 times the Lawson critera of D-T, that is, it requires 30 times the confinement. D-D has 1/68 of the power density of D-D. All other reactions are much worse.

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Paul Studier

ITER already works. It is doing precisely the job for which it was intended and it will keep doing it magnificently for many decades to come.

The mental confusion comes about because its real mission isn't the one that the public is told, but it's pretty obvious for any technical person who spends more than about five minutes thinking about it.

On a similar note, I wasted the first ten years of my career at NASA trying to lower the cost of putting things in space and moving them around when I got there. If I could go back in time, to early 2000 when I was just starting at NASA and holding "Fluid Fuel Reactors" in my hand, I'd tell myself a few things:

"Kirk, NASA doesn't want to save any money. You'll just make them mad if you try to save money. The more you can save, the madder you'll make them."

"Kirk, that book in your hand. It's important. More important than anything else that's going on around here."

It is frustrating when otherwise well educated men and women become fixated on less than optimal choices of direction. I know there are unexpected breakthroughs which were unpredicted and which have happened when logic suggested otherwise, but in energy, there is a huge gap between things we could do that we know could be extremely useful and beneficial to society and wild goose chases that simply spend money and confuse the less knowledgeable with unrealistic hopes for magical outcomes. What could have been accomplished with only 10 percent of the money we have wasted chasing energy dreams? Society could have been so much better off.

I am all for frontier area research (I cheered the Higgs discovery at CERN,) but I am also one who believes identifiable goals of merit for mankind should be supported. We choose to do cancer research as a targeted goal, and I am fine with that. I just want balance in how we pursue needed goals and how we seek new knowledge. What I have seen over the last several years is quite strange from a logical point of view -- we need reliable dense energy. But I admit to being opinionated. Fusion was a pipedream in the 1960s when we could not control the confinement, density, and energy parameters, and it is still a pipedream to think we can create the conditions of a stellar reactor in a laboratory in a cold, weak, directional gravitational field and achieve the amount of controlled energy output to reliably power civilization. But maybe saying all that is similar to Lord Kelvin thinking we had all the science we needed at the end of the 1800s.

That's explains why there is still a nuclear waste problem in this country.

Well actually, there is no nuclear waste problem, quite literally. Almost all of it is a useful resource for the future and it is easy cheap and safe to store for as long as needed with a variety of methods.

There may be a link though. Governments, it turns out, are very good at throwing money at problems that aren't (Yucca Mountain) and solutions that will never be (ITER).

Just like the solar roadways campaign on Indiegogo.com. They want to cover the world's roads, sidewalks, and parking lots with pressure sensing solar panels, covered in LED's. They've received $2.2 million for production costs. Unfortunately, it takes about 10 seconds with a calculator to see how absurd the idea is. They also claim the panels will have heating elements to melt snow/ice and yet will still produce enough power to contribute to the grid. Some have started to catch on to the absurdity, but not before 48,000 people were duped out of their cash.

Yeah, I read about the roadways.... I can just imagine a serious ice storm and all the power it would require to melt the ice. There are so many long shot hopes and thermodynamic hurdles involved in the solar road dream that I do not see who would cough up funding for it. My windshield becomes more opaque each day I drive between washings, what would it look like after countless tire tracks and natural dirty accumulations if it were a roadbed? Also, it would give potholes a whole new level of importance. Something worth a lot more would be a more durable road bed that annealed itself to a smoother surface rather than a harmonically pumped wobbly surface once an imperfection appears. Put all that effort in a self-healing anti-pothole surface and you could fund about anything you wanted. Both things might be about equally likely (or unlikely.)

The most recent cost estimate for the finished ITER is about $50 billion.

So using my costing method that would be equivalent of $500/Watt.

The ITER website has some facts which they use to brag about the project but they are also clues as to why the cost is so high:

http://www.iter.org/factsfigures

All that zero electric output, or 0.1 GWe to the grid if it actually had a powerplant.

The reactor core (plasma volume) of 840 m3 means 0.12 MWe/m3. This compares to 36 MWe/m3 for a PWR.

23000 tonnes for 100 MWe is 230 tonnes/MWe. The Tokamak alone has several times the total metal of a PWR.

The 360,000 tonnes basemat is a massive 3600 tonnes/MWe.

5000 workers for a 0.1 GWe powerplant is totally crazy. For comparison a twin AP1000 plant, 2.3 GWe, has a peak worker need of 3000. So on a per MWe basis fusion apparently needs 38x more workers. Bearing in mind the ITER won't actually have a powerplant, which increases workers needed further.

Its not really fair to use ITER to damn Tokamaks.
It is not built as a power plant - its built to show that ignition in a Tokamak is actually possible and very little else.

Plasma Physicists have been burned enough times by claims that they are building the most conservative machine they could possibly concieve.
Its massively overengineered.
Also DEMO is only projected to have ~45% greater volume but also have a thermal output of ~2000MWt.

If the scaling rules work this time the reactors will get very big very rapidly.
And thanks to the low pressure differentials across the reactor walls we can build enormous vessels.

What basis do you have for this assertion? Do you think a power generator needs 1% the equipment of the test reactor? Do you think adding power generating machinery will reduce the cost to 1%?



You and I have different definitions of massively overengineered. A pressure vessel that operates at 5% its rupture strength is massively overengineered. A powerplant that with state of the art technology that can't be expected to last for more than 10 minutes at this point in time, is not massively overengineered. Recent estimates for the carbon composite helium exhaust suggest it would between 3 weeks and 3 months.



Scaling rules don't seem to work for PWRs. Small ones were built for $200/kWe in the early days. Now big ones cost over $5000/kWe. Clearly other factors determine cost.



Enormous vessels and low plasma power density are part of the cost problem. You can't have a small vessel anyway because most of the energy is emanating through the reactor vessel. Its like trying to generate power with a PWR but in stead of a tube-and-shell steam generator you're only allowed to use the main pressure vessel as the steam generator!!

I'm willing to buy into a scaleup law of 2x cost reduction per Watt, and another 2x for improved efficiency and reduced self consumption. This still puts you at $125/Watt. Maybe you can cut it in half again by eliminating the experimental stuff that you don't need in a power generator. Still $62/Watt. See how hard it is to get within the realm of coal or LWRs even if you assume big improvements?

I believe he was talking about power output scaling, not cost scaling.

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DRJ : Engineer - NAVSEA : (Retired)

Yes but they are related. If you can get 2000 MWt out of a 500 MWt reactor but not add much equipment the cost is reduced drastically.

I actually doubt DEMO will be built at all. 50 billion for ITER is crazy.

Why the World's Largest Nuclear Fusion Project May Never Succeed



Short answer, too expensive.

New schedule agreed for Iter fusion project



So in six years they've slipped the schedule six years. What a waste of time, money, and scientific talent.