Talk-Polywell.org

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ITER Problems

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edge localised modes

This shows yet another time how stubborn and blind could scientists be. Tokamak designs have proven time and again over the years that the design is mind bogglingly complicated and generally flawed. If it had the produce energy it would have done so long ago. The simply cannot convince me that they are on the right track simply because there are no torroidal shaped stars.
This monstrosity has engulfed billions already and is continuing to do so only to discover new obstacles. The greatest achievement of the lobbyists is that they continue to sweet talk governments of receiving huge amounts funding over so many decades without any positive result whatsoever. Hats down to that

Skytreker wrote:This shows yet another time how stubborn and blind could scientists be. Tokamak designs have proven time and again over the years that the design is mind bogglingly complicated and generally flawed. If it had the produce energy it would have done so long ago. The simply cannot convince me that they are on the right track simply because there are no torroidal shaped stars.
This monstrosity has engulfed billions already and is continuing to do so only to discover new obstacles. The greatest achievement of the lobbyists is that they continue to sweet talk governments of receiving huge amounts funding over so many decades without any positive result whatsoever. Hats down to that :(

Bussard (and small fusion in general) now has its own (citizen) lobby. So there are countervailing forces.

An ITER guy commenting on the cut in US ITER funds says it was the will of the people. He got that right.

We really need to diversify our fusion research much more than we have 'til now.

Diversifying is good. Shooting the frontrunner in a foot race, however, never makes for a better race. 10B Euros over the next decade isn't too much to spend on ITER by any means, and US participation is vital to our moving forward on all of this.

Helius wrote:Diversifying is good. Shooting the frontrunner in a foot race, however, never makes for a better race. 10B Euros over the next decade isn't too much to spend on ITER by any means, and US participation is vital to our moving forward on all of this.

The front runner in this race is making good time (relatively) due to a 100,000 HP engine. The ITER folks estimate they will need a 1,000,000 JP engine to complete the race. And at the end future races will require big engines due to the inherent friction of the design.

Bussard fusion is making better time with a 200 HP engine and estimates a 2,000 HP engine will help them complete the race. In future races they estimate a relatively small engine will be a race winner. The Bussard team is underfunded.

ITER is NEVER going to produce a commercially viable reactor. Current estimates are that Tokamak fusion will come in at 5X to 10X current electrical energy prices. Which would make it 2X to 5X more costly than current wind power. Wind power will achieve parity with coal in the next 5 to 10 years. So relative to ITER it will only get worse.

If it weren't for the physics we would be better off spending ITER money on wind turbines.

In any case most of the rest of the world still has faith in ITER so the worst that will happen is that the project will get dragged out - if Bussard Fusion doesn't put them out of business with its success. US participation is not vital. Useful maybe. Vital? No.

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In addition: we know of no way to make ITER a better bet other that building it bigger.

With the BFR we have POPS. We have the possibility of focusing grids. And possibly other low cost tricks tricks to enhance the Q.

I found it amusing they were deliberately creating instabilities in order to correct another instability.

I wonder how significantly the deliberate instabilities they're inducing with the "belt and braces" and frozen pellets push down the Q.

Norbert Holtkamp, the project's construction leader, will be told to use a complex arrangement of magnets to dampen the effects of the erosive blasts, by in effect poking holes in the reactor's magnetic bottle to bleed out some energy.

Argh. Yeah, that's just what you want to be doing in a thermal scheme where temperature is the critical factor.

ITER is NEVER going to produce a commercially viable reactor.

Well, I hate to say never. Given huge advances in materials science and plasma dynamics, it might someday be possible, esp. if the cheaper fossil/biomass fuel energy sources are exhausted or very very expensive.

But even then, given that fission reactors are already competitive, it's very hard to envision a tokamak being commercially viable.

TallDave wrote:I found it amusing they were deliberately creating instabilities in order to correct another instability.

Yeah. That amused me too. What they are attempting to do is to create a system with no resonances across a very broad range of frequencies.

If nothing else they have the problem of a gas in an acoustically resonant cavity. The more damping they eliminate (the better the confinement) the harder it will be (except electronically) to damp the various oscillation modes (acoustic and electrical).

The BFR can be adapted to usefully enhance those modes (POPS).

Controlling an oscillator is an easier trick than electrically damping one.

Better phrasing:

Feeding power into a resonance is easier than electronically damping one.

MSimon wrote:

Helius wrote:Diversifying is good. Shooting the frontrunner in a foot race, however, never makes for a better race. 10B Euros over the next decade isn't too much to spend on ITER by any means, and US participation is vital to our moving forward on all of this.

The front runner in this race is making good time (relatively) due to a 100,000 HP engine. The ITER folks estimate they will need a 1,000,000 JP engine to complete the race. And at the end future races will require big engines due to the inherent friction of the design.

Bussard fusion is making better time with a 200 HP engine and estimates a 2,000 HP engine will help them complete the race. In future races they estimate a relatively small engine will be a race winner. The Bussard team is underfunded.

ITER is NEVER going to produce a commercially viable reactor. Current estimates are that Tokamak fusion will come in at 5X to 10X current electrical energy prices. Which would make it 2X to 5X more costly than current wind power. Wind power will achieve parity with coal in the next 5 to 10 years. So relative to ITER it will only get worse.

If it weren't for the physics we would be better off spending ITER money on wind turbines.

In any case most of the rest of the world still has faith in ITER so the worst that will happen is that the project will get dragged out - if Bussard Fusion doesn't put them out of business with its success. US participation is not vital. Useful maybe. Vital? No.

=========

In addition: we know of no way to make ITER a better bet other that building it bigger.

With the BFR we have POPS. We have the possibility of focusing grids. And possibly other low cost tricks tricks to enhance the Q.

ITER doesn't have to produce commercial fusion power to be useful, neither does DEMO for that matter. If they can produce fusion plasma enviroment to test new plasma facing materials capable of withstanding high plasma fluxes aswell as testing the ability of fusion blanket materials for absorbing fast neutrons and breeding tritium, then they will give all alternative fusion schemes a head start in materials, blanket and coolant systems techology for a wide range of generic fusion devices.

Regarding the patches on patches argument, this is the same for every fusion scheme. I can guarantee you that the BFR will not achieve breakeven in one clean shot but instead will require continuous patches to solve the various new problems as fast as they appear, the same applies to mirror machines stellerators and any other concieveably fusion scheme that can be imagined. The fact that the Tokamak has got so many patches and is such a complicated device is simply a sign that its approaching the final goal of net fusion power.

It would be wonderful if there was another simpler cheaper device that could be built capable of producing fusion power instead of the tokamak, but no such device exists, JET is the closest thing to continuous high-peformance fusion operation around. The most reliable route to fusion plasmas would then be to run with that idea and see how far we can take it.

The other approaches may indeed work but there is no timetable for their success, they could take 10, 20, 30, 40 or 50 more years before they catch up with the tokamak, the fusion materials development programme is liable to be held up until a machine exists where the new materials and components can actually be tested in a fusion environment, can we take the gamble that these other approaches will be ready in time?

Much better to continue the tokamak programme with the minimum funds necessary to achieve a useful fusion components test environment while at the same time pursuing other approaches that promise to give us a cheaper fusion reactor.

All in all, given the potential benefits of fusion from an energy point of view, it deserves more overall funding, enough funding to for tokamaks to coexist with other approaches without strangling them.

Whether or not wind is catching up with coal joule for joule a well designed fusion reactor is likely to be more land efficient then hundreds of square miles of wind turbines, in addition to not wasting land this will make it easier to maintain as oppose to having maintenance crews driving around the middle of nowhere repairing turbines here and there, it also makes fusion reactors simpler to guard than wind turbines from sabbateurs and terrorists. Fusion reactors also are likely to be capable of producing energy as required rather than in unpredictable spikes which will make them simpler for the grid (although I realise there are solutions such as flow batteries in the case of wind power, how much they will cost once they are scaled up is another question). You also can't build a wind-power spaceship or use windpower to supply energy to a colony on the moon.

I certainly don't think the decreasing cost of wind or solar is sufficient grounds to abandon the fusion programme.

Whether or not wind is catching up with coal joule for joule a well designed fusion reactor is likely to be more land efficient then hundreds of square miles of wind turbines, in addition to not wasting land...

Actual land use is .25% of the land area over which the turbines are deployed. That includes access roads.

In America the turbines will go up on farm land in the MidWest. Farmers will harvest energy and food.

There is no a land use problem.

In addition wind costs are declining in the same way they did from 1900 to 1950. For the same reason. Bigger turbines - better economies of scale. There are at least 2 more doublings to go. Each doubling reduces costs by 1/3. Two doublings will reduce costs by better than 50%.

With wind we are in known territory. The road map is clear. With fusion - not so much.

As to saboteurs and terrorists - how many turbines do you have to take out to cause a significant problem? More than 1. Probably more than 10. Knocking out transmission pylons would have more effect.

I'm not arguing to end fusion research. I'm just saying smaller experiments give more bang for the buck at our current level of ignorance.

BFRs do have a timetable. If it can't be worked out in 5 years it is probably not worth pursuing.

With the tok guys it is always "we can get it to work if we make it 3X larger".

I would argue that even with wind it's not clear how that would work. Much wind energy is far away from its intended destination.

scareduck wrote:I would argue that even with wind it's not clear how that would work. Much wind energy is far away from its intended destination.

HVDC transmission. We know how to do it. The question is demand.

Currently demand in the US is growing 2X as fast as supply.

If it weren't for the physics we would be better off spending ITER money on wind turbines.

In my humble opinion, on fission designs it would be better spent.

It was compared that a fission reactor producing roughly the same amount of heat as proposed future Tokamaks would, at 1/3rth of the price and several times much more reliable. Unlike fusion, fission is true and tested, with lots of operation experience.

That is not to say that wind turbines are bad, its just that it has its place. Wind turbines are good at topping high demand, but for baseline power, you want fission. You get energy for wind turbines when there is wind, you get fission energy till there is enough unstable high-z fuel being radioactive. Wind is unpredictable while fission runs 24/7 (hours/days a week).

Wind energy is good when you want to give energy to complete what fission plants give. It is also good where power lines are difficult to implant, ie, rural areas.

However, if you want to power as something big as a city, you want something big and powerful. That's fission plants.

There is no reason why the two is mutually exclusive.

Zixinus wrote:That is not to say that wind turbines are bad, its just that it has its place. Wind turbines are good at topping high demand, but for baseline power, you want fission. You get energy for wind turbines when there is wind, you get fission energy till there is enough unstable high-z fuel being radioactive. Wind is unpredictable while fission runs 24/7 (hours/days a week).

Wind energy is good when you want to give energy to complete what fission plants give. It is also good where power lines are difficult to implant, ie, rural areas.

However, if you want to power as something big as a city, you want something big and powerful. That's fission plants.

There is no reason why the two is mutually exclusive.

Two points - distributed wind is good for baseline at 20% of rated turbine capacity. Which is not bad given that total average output is 33% of rated capacity.

Second - we don't build power plants near big cities (generally). The power is delivered by the grid. There is nothing wrong with collecting energy over a wide area and delivering it to a concentrated load. Depending on the economics.

People really get confused re: wind. The thought patterns generally run in the "what will one isolated turbine be like" vs the real way a widely distributed system connected to the grid operates.

I find that unless the person has studied the whole wind deal intensively there are a lot of errors in understanding. That goes for engineers as well as laymen.

Second - we don't build power plants near big cities (generally).

I've never said that it should be built near to a big city. I said that to power a city, you need something big and powerful. Small towns and villages can be run on renewable energy sources, but factories with big businesses have high demand and little tolerance for unpredictable fluctuations.