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Super-Soaker inventor may have solar-powered fuel cell breakthrough

theatlantic.com

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Re: Super-Soaker inventor may have solar-powered fuel cell breakthrough

#41

Post by tocomment »

gvb wrote: post #28
tocomment wrote: post #7

How would this work? Surely sunlight can't create enough heat to ionize a gas (creating plasma?). Why don't the whole hydrogen atoms go through the membrane to the lower pressure area? How does he alternate which side is heated? How does he cool the other side?

> How would this work? Surely sunlight can't create enough heat to ionize a gas (creating plasma?). He isn't ionizing the gas, he is increasing the gas pressure by heating it. "Only instead of using those pressure gradients to move an axle or a wheel, he’s forcing ions through a membrane." See next for why that is important. > Why don't the whole hydrogen atoms go through the membrane to the lower pressure area? He u…

So if the sunlit side is under higher pressure, how do the hydrogen atoms return to that side? I must still be missing something.

Also, is there really enough hydrogen ionizing at 400C?

Re: Super-Soaker inventor may have solar-powered fuel cell breakthrough

#42

Post by anthonyb »

kjuhygtfrde wrote: post #36
anthonyb wrote: post #26

Earlier quoted context omitted.

Sure it can - you just have to focus the sun's rays into a smaller area. The sun delivers on the order of 1000W per sqm during the day, so (eg.) focusing 100 sqm into 1 sqm == 100,000W. 12 hours of daylight will then give you a theoretical production of 1.2MWh per day, but it's usually a lot less, due to the angle of the sun in the morning/evening and inefficiencies in your energy capture.

On HN we obey the 2nd law of thermodynamics

That entropy always increases? How exactly does that apply in the case of focusing photons?

Re: Super-Soaker inventor may have solar-powered fuel cell breakthrough

#43

Post by brianbreslin »

rajat wrote: post #30

I don't get it. Why isn't Google investing in this along with robot self-driving cars? Why isn't Khosla investing in this? Or is this the article that gets them interested? I don't pretend to have the engineering knowledge to know whether this will work or not, whether it's snake oil or not, but surely, if an electric sports car for the rich can get funded, so can this guy. I'm assuming the guy isn't peddling snake-o…

IT seems that he has focused on the academic side of this more than commercial, though he seems to have a staff suitable to commercializing this. Maybe the DARPA or whomever gives him better terms on his deal than he'd get from Khosla?

It does mention PARC investing and owning parts of his patents.

Re: Super-Soaker inventor may have solar-powered fuel cell breakthrough

#44

Post by aphyr »

shasta wrote: post #17
MaysonL wrote: post #13

Earlier quoted context omitted.

The maximum heat you can get from sunlight is the temperature of the sun: definitely hot enough to ionize most gases.

Right. Cuz the photons are the same temperature as the sun. That's why sun photons feel warm.

It's more true than you might think. http://en.wikipedia.org/wiki/Plancks_law

Re: Super-Soaker inventor may have solar-powered fuel cell breakthrough

#45

Post by brianbreslin »

gvb wrote: post #29
kenjackson wrote: post #11

This is like the ultime HN article. * Born hacker * Issues of race and oppression * Entreprenuer spirit * Issues with patents * Big companies stifling innovation Someone should write "Inventors at Work".

* Experts tell him it won't work and point out the PhD thesis (or equivalent) that "proves" it... however, he is attacking the problem in a different way that the expert did not expect.

Proof that sometimes an outsiders perspective can come at a problem in a novel and seemingly successful way.

Re: Super-Soaker inventor may have solar-powered fuel cell breakthrough

#46

Post by jacquesm »

Sorry guys, I got there first:

http://pics.ww.com/v/jacques/renewables/concentrator/

Patent pending ;)

Yes, I realize there is a lot more to it than that. However, there have been solar concentrators of all kinds of varieties, I've built a couple of proto-types the one in the pictures above was one of the more promising ones because it allows the collector to be stationary.

Interesting tidbit from that experiment, it's quite hard to bond a solar panel to a cooling surface that can dissipate 800 watts over 100 square centimeters, whatever you use to bond will melt or dry out and then your solar cells will self-disassemble. So you will end up with active cooling, which in turn will give you co-generation (both electricity and heat).

I really hope this guy will succeed, we could do with a bit more radical thinking in this space.

Re: Super-Soaker inventor may have solar-powered fuel cell breakthrough

#47

Post by kjuhygtfrde »

anthonyb wrote: post #42
kjuhygtfrde wrote: post #36

Earlier quoted context omitted.

On HN we obey the 2nd law of thermodynamics

That entropy always increases? How exactly does that apply in the case of focusing photons?

Another way of stating it is that heat flows from hot->cold. You can't concentrate the light/heat from a blackbody source to more than the temperature of the source.

So you can't focus sunlight to more than 6000k however many mirrors you use.

Re: Super-Soaker inventor may have solar-powered fuel cell breakthrough

#48

Post by MaysonL »

shasta wrote: post #17
MaysonL wrote: post #13

Earlier quoted context omitted.

The maximum heat you can get from sunlight is the temperature of the sun: definitely hot enough to ionize most gases.

Right. Cuz the photons are the same temperature as the sun. That's why sun photons feel warm.

see: http://www.physicsforums.com/showthread.php?t=349697

Re: Super-Soaker inventor may have solar-powered fuel cell breakthrough

#49

Post by brc »

brc wrote: post #8

The Lesson here is : if you do make a pile of cash, lock some of it away so that you and your family have an (almost) assured retirement plan.

I don't understand the downvoting, so I'll make my position clear. If you read the article, the guy is now in financial trouble because the super soaker profits have largely dried up, and he has had to put other plans on hold.

What I'm saying is, if you find yourself in the situation where you have a big win, you need to lock away some of that to keep you in retirement. Then, you can go onto your next venture knowing that, if it doesn't work out, at least you won't fall on financial hard times. I honestly don't know why this is so downvoted, so perhaps someone can explain it to me.

Re: Super-Soaker inventor may have solar-powered fuel cell breakthrough

#50

Post by gallerytungsten »

I find the story very inspiring, but as some others noted, it would be nice to see a working model of the unit, or at least some pictures.

Now on a more substantial level, the claims of "60% efficiency" and "on part with coal" claims are interesting and need a little more explanation, in my opinion. How are these numbers being calculated? We aren't told.

One might guess it's based on a bunch of manufacturing and startup costs, along with operating costs, for an unknown number of years (probably many) along with projections about various other future costs. What power levels will a prototype produce, and how will it be scaled up?

I think the concept sounds promising, but a lot of questions remain to be answered.

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