Energy - again

[lenord]

All,


Since we seem to have some interesting discussions about energy here, that I learn a lot from, what do y'all think of this thread over at the other site ?

http://www.practicalmachinist.com/vb...d.php?t=149324

Lenord

[Carld]

Chemical reactions like that are beyond my knowledge. If it works that's great, if it don't we won't hear from that idea again.

[Evan]

Sounds feasible, not bunk. Membrane electrode assemblies are proven technology used in hydrogen fuel cells. It sounds like what he is doing is operating a hydrogen fuel cell where the hydrogen is reformed after burning by means of the solar heat input. The description is lacking in detail but the information that is given is scientifically accurate and recognizes the appropriate bounds placed on efficiency of heat engines. I do think the 60% figure is much too optimistic and the statement that a hot side temp of 600 degrees C is enough to reach 60% efficiency is only theoretically possible but never in practice. Losses will require a much hotter hot side to approach 60% efficiency. It is possible as today's combined cycle gas turbine power plants are reaching 60%.

[ckelloug]

I can't say that I fully understand. . . but in that the article talks about the device being Carnot limited and since everybody in the article is admitting that, it passes the sniff test. Since it can operate at high temperatures and has no moving parts, the 60% efficiency they cite sounds possible.

Nobody mentioned zero-point energy, contradictions in Maxwell's equations, imploding hydrogen or the other reams of gibberish that automatically signify gross fraud.

Kudos to the guy. I hope it gets into production ASAP.

--Cameron

[aostling]

It could be something. He claims it runs on the Ericsson Cycle. This, and the Stirling Cycle, has the same theoretical efficiency as the Carnot Cycle. This is given by

efficiency = 1 - T(cold)/T(hot).

If the engine runs with source and sink temperatures of 1073 kelvin (800˚C) and 293 kelvin (20˚C) respectively, this corresponds to a theoretical efficiency of 73%. So perhaps his claim of achieving 60% efficiency is practical.

[barts]

If it actually works and isn't to expensive, it would work very nicely as part of co-generation for household furnace & hot water heater; burn natural gas
@ stoichiometric conditions; generate electricity and then reject heat at 110F for household heat & hot water....

It would also permit more simple extraction of energy from biomass.... a small wood fire at even 25% efficiency would power a cruising boat very easily.


- Bart

[2ManyHobbies]

Kudos if it works, but 1100 F? Iron starts to glow around that neighborhood.

My thought is maybe this would be something that would apply to a multi-acre reflector setup, and perhaps be less than idea for residential setups. It sounds almost like skipping a step (or two) and avoiding those losses. Almost like skip the turbine/generator and tap the heat exchanger for voltage.

[Evan]

Kudos if it works, but 1100 F? Iron starts to glow around that neighborhood.

Water also dissociates to hydrogen and oxygen given the right conditions at that temperature. I have seen other work on solar powered dissociation of water to obtain hydrogen. If the entire cycle can be canned without moving parts it would be a very considerable advance regardless of the ultimate efficiency.