A new approach for thermal energy conversion might improve efficiency

[Breakable]

http://www.theatlantic.com/magazine/archive/2010/11/shooting-for-the-sun/8268/1/

http://www.johnsonems.com/?q=node/2

[zapkitty]

Breakable wrote: http://www.theatlantic.com/magazine/archive/2010/11/shooting-for-the-sun/8268/1/

http://www.johnsonems.com/?q=node/2

This tech has been hanging fire for a while… to the point where I’d put it in the “It’d be nice” territory.

The numbers are good and depending on loop arrangements and temps you could have anywhere from current FF projections (~5MWe and ~8MWt) up to 8MWe/5MWt…

…but could the JTEC be considered any closer to reality than the “onion”?

[Breakable]

zapkitty wrote:
…but could the JTEC be considered any closer to reality than the “onion”?

Yes, definitely. They have some stuff for JTEC that is already working (as I understood from the article they had the fuel cell membrane long time ago).
And AFAIK there needs to be a lot of work done to even get the “onion” project proof of concept funded.

[zapkitty]

Breakable wrote:

…but could the JTEC be considered any closer to reality than the “onion”?

Yes, definitely. They have some stuff for JTEC that is already working (as I understood from the article they had the fuel cell membrane long time ago).
And AFAIK there needs to be a lot of work done to even get the “onion” project proof of concept funded.

… that was my point: JTEC’s been jammed up for years because of financing and, apparently, because of Johnson’s worries about control issues.

The tech is not really usable if it’s tied up or locked down… even if the blockages are for non-technical reasons.

[Henning]

It’s a long and exhausting story but its general function is cited here:

Johnson’s latest JTEC prototype, which looks like a desktop model for a next-generation moonshine still, features two fuel-cell-like stacks, or chambers, filled with hydrogen gas and connected by steel tubes with round pressure gauges. Where a steam engine uses the heat generated by burning coal to create steam pressure and move mechanical elements, the JTEC uses heat (from the sun, for instance) to expand hydrogen atoms in one stack. The expanding atoms, each made up of a proton and an electron, split apart, and the freed electrons travel through an external circuit as electric current, charging a battery or performing some other useful work. Meanwhile the positively charged protons, also known as ions, squeeze through a specially designed proton-exchange membrane (one of the JTEC elements borrowed from fuel cells) and combine with the electrons on the other side, reconstituting the hydrogen, which is compressed and pumped back into the hot stack. As long as heat is supplied, the cycle continues indefinitely.

As he is just using hydrogen gas, this makes a great drop-in for the cooling circuits of the electrodes and onion. Where we’ve intended elsewhere in the forum to use helium. So the gas is not used in a steam/liquid cycle.

Maybe it’s worth contacting him with the intention of introducing him to the idea of focus fusion. An invitation to LPP’s lab? Maybe he’s curious?

[Henning]

Here’a bit about it on PESWiki.

And a working link to his research company: johnsonrd.com

And his battery company: Excellatron

[Brian H]

zapkitty wrote:
…

The numbers are good and depending on loop arrangements and temps you could have anywhere from current FF projections (~5MWe and ~8MWt) up to 8MWe/5MWt…

…but could the JTEC be considered any closer to reality than the “onion”?

Actually, the numbers suck. They are “hoping” to get the cost/kwh down to “half” of 25¢ — which is 12.5¢/kwh. Which is about 50X as high as the output from FF.

There is NO arrangement, regime, or setup whereby a 50X higher cost technology can improve on the net costs of FF. I.e., every kwh thus recovered/salvaged from the “waste heat” could have been provided at 2% of that price from another FF.

Fuggedaboudit.

[zapkitty]

Brian H wrote:

…

The numbers are good and depending on loop arrangements and temps you could have anywhere from current FF projections (~5MWe and ~8MWt) up to 8MWe/5MWt…

…but could the JTEC be considered any closer to reality than the “onion”?

Actually, the numbers suck. They are “hoping” to get the cost/kwh down to “half” of 25¢ — which is 12.5¢/kwh. Which is about 50X as high as the output from FF.

There is NO arrangement, regime, or setup whereby a 50X higher cost technology can improve on the net costs of FF. I.e., every kwh thus recovered/salvaged from the “waste heat” could have been provided at 2% of that price from another FF.

Fuggedaboudit.

*bleep!*

I missed the cost estimate and it’s implications.

Back to the onion…

… or, say, anyone work out at what point even a marginal net power profit from the alpha beam alone would allow an FF to be competitive?

[Aeronaut]

Brian has a blind spot which prevents him from readily acknowledging that the first salable FF units will be producing a thermal profit. Succeeding generations may or may not offer the onion. Depends on engineering not just the onion, but the production tooling for the experiments and the factories. Thus JTEC may play a part in FF validation and at least the early marketing.

[Brian H]

Aeronaut wrote: Brian has a blind spot which prevents him from readily acknowledging that the first salable FF units will be producing a thermal profit. Succeeding generations may or may not offer the onion. Depends on engineering not just the onion, but the production tooling for the experiments and the factories. Thus JTEC may play a part in FF validation and at least the early marketing.

And Aero won’t take on board that there is no possible way to spend money on recovering this “thermal profit” which isn’t vastly more expensive than just generating the heat with simple resistance coils run by watts from another FF.

Accounting trumps engineering.

[Aeronaut]

Brian has yet to specify the nature and expense of his version of a dedicated cooling system. My approach is opportunistic- look for existing heat loads (like the JTEC in this case) to use as the FF’s heat-sink. Thus the accounting equations may not be the ones Brian was planning to use to justify resistance heaters. BTW, how would those be powered in a FF gen-1?

[Brian H]

Aeronaut wrote: Brian has yet to specify the nature and expense of his version of a dedicated cooling system. My approach is opportunistic- look for existing heat loads (like the JTEC in this case) to use as the FF’s heat-sink. Thus the accounting equations may not be the ones Brian was planning to use to justify resistance heaters. BTW, how would those be powered in a FF gen-1?

Ah, now we’re talking accounting! Since the cooling mechanisms must be there anyway, if they could be tweaked to make some worthwhile use of the heat they extract without adding more cost/kwh than the replacement with output from another FF would be, then it could make sense. But here the onus, in reality (i.e., $$ expended) as opposed to wishful thinking, is on those advocating such tweaking.

I don’t have to specify anything whatsoever about a “dedicated cooling system”, since it is inherent and necessary to any FF installation to keep it from melting down. That’s a given, the start point. Now justify making KW out of that extracted heat — and note that your added costs MUST BE less than ¼¢/kwh. (Even using the extracted heat for simple passive warming of buildings etc. must meet this test. And it’s a very difficult, severe, test indeed!) ,

[Aeronaut]

Brian H wrote:

Brian has yet to specify the nature and expense of his version of a dedicated cooling system. My approach is opportunistic- look for existing heat loads (like the JTEC in this case) to use as the FF’s heat-sink. Thus the accounting equations may not be the ones Brian was planning to use to justify resistance heaters. BTW, how would those be powered in a FF gen-1?

Ah, now we’re talking accounting! Since the cooling mechanisms must be there anyway, if they could be tweaked to make some worthwhile use of the heat they extract without adding more cost/kwh than the replacement with output from another FF would be, then it could make sense. But here the onus, in reality (i.e., $$ expended) as opposed to wishful thinking, is on those advocating such tweaking.

I don’t have to specify anything whatsoever about a “dedicated cooling system”, since it is inherent and necessary to any FF installation to keep it from melting down. That’s a given, the start point. Now justify making KW out of that extracted heat — and note that your added costs MUST BE less than ¼¢/kwh. (Even using the extracted heat for simple passive warming of buildings etc. must meet this test. And it’s a very difficult, severe, test indeed!) ,

If you don’t need to submit proof, then FF must also need no proof. A more coherent argument (not necessarily the best one possible) would be to link to Rematog’s cooling tower design and costing link, where Lerner also estimated the costs of using multiple car radiators. Either would provide sufficient cooling structure and cost estimation to convince me that you’ve done your homework. A non-purist’s viewpoint is to market what works until you can make the ideal, complete system marketable. JTEC gives us another potential way to turn all of that waste heat, which may turn out to be a crime in a multi-fusion world, into at least a stopgap way to make commercial quantities of electricity before the onion is marketable hardware.

Remember, it wasn’t really a crime to burn fossil fuels until the friendly folks at Dopenhagen politely requested we pay reparations for all of those decades of criminal neglect. :shut:

[zapkitty]

errrrrrrrr… it seems to me that the question relies upon the actual efficiency of the default FF conversion method… the onion.

If the onion proves to be more economical than any given thermoelectric solution then thermoelectric solutions can never catch up, right?

And if a thermoelectric solution can economically make use of even the leftover heat from the onion then that solution theoretically can just replace the onion, right?

Or is this all just a rehash of Aeronaut’s meme that an FF without an onion or thermoelectric solution still has a future as a replacement for other heat sources?

[Brian H]

Sorry, Aero. Not buying. The FF MUST be cooled, recovery or no, or the electrodes will melt (remember them?). Recovery equipment is therefore an added cost, which must justify itself. In $$, which means recovered kwh’s from the waste heat at =<¼¢ each, and capital cost added at =<5¢/W. Good luck with that. If such technology existed, it would already be in use wherever low-grade waste heat is to be found. And there would be no market or need for Fofuz.

I spent years working in auditing and accounting. Costs must be allocated to the activity they support, or a financial statement is false, even fraudulent.

[Author]

Posts