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Re: Solar-hydrogen home power system?

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Don W.

Jan 1, 1970
0
"Thomas Lee Elifritz" says...
Well, you could participate, it's called condensed matter physics,
employment is guaranteed.
I wonder if Thomas Lee Elifritz has a job?

Don W.
 
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Roland PJ

Jan 1, 1970
0
Don said:
Right.
The exergy goes sharply down when you include the storage charges.

Don, you're missing the point.

Isolated/stored hydrogen has way more exergy than 'unstored'/air-mixed
hydrogen.

Your premises might be unfounded.

Rolando
 
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Roland PJ

Jan 1, 1970
0
Don said:
Glenn Martin wrote:




Energy density has everything to do with a fixed installation.

The cost of the installation is inversely proportional to the CUBE of
the energy density.
But the storage can be used many times over.

What's your point?

Rolando
 
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Roland PJ

Jan 1, 1970
0
Don Lancaster wrote:
If someone gave you an infinite supply of six percent efficient solar
cells, there is no way you could profit from them. The costs of the
infrastructure and amortization would guarantee you a net energy sink.

Similarly, no means of storing hydrogen is known that does not grossly
exceed the value of the stored energy.
Ummm, yes I could profit from them. I could use them to power my lights.

Why do you tack on 'infrastructure and amortization' when you're
presenting a free service?

What's your angle, dude?

Roland
 
G

Glenn Martin

Jan 1, 1970
0
Anthony Matonak said:
This will give you the Burden of Civilization per object installed.
Since this will be a complex series of resources, man-hours and
other such things, Don might suggest reducing it to the common and
universal unit of Gallons-of-Gasoline because everything is really
made from that anyhow.

Looked at in this fashion, nearly everything is a complete net
loss. Well, except for Gasoline of course... :)

Anthony

Don keeps equating dollars with gasoline.
The only problem is that a dollar of gasoline today is larger or smaller
than a dollar of gasoline tomorrow. This truely is comparing apples to
oranges.
Dollars are an intellectual construct we all buy into to make our lives
easier. Instead of metal or the paper representation of same, most takes
the form of ones and zeroes in electronic memory.
Gasoline is a physical substance. A FINITE physical substance. There is
no interest plan that would let me put a barrel of oil into a savings
account and get more oil out of it later. If I put money I could invest in
alternative power generation into a savings account instead, I might have
more money to buy gas in twenty years. But with increasing world demand
and the high possibility that we'll have passed the peak recovery point for
oil reserves, I might easily end up with less gas for my money. This is
poor economics and poor engineering.
I've never read these considerations in any of Dons' writings and he keeps
refusing to answer thes objections to any of his posts.
Another thing to consider is the huge scare an oil crunch would put into
the world economy. Maybe the best thing to do with money now is invest in
alternative power generation.

Glenn Martin
 
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Glenn Martin

Jan 1, 1970
0
Gymmy Bob said:
Quite simply put, for some of the boneheads here.

If the payback for solar panel system is 10 years to the breakeven point
and the electrolysis process is 40% efficient, then the payback for your
hydrogen for solar system is 25 years.

How long will you live past 25 years to make a profit from it? Will the
solar cells last that long? Will your electrodes last that long? What will
you store the hydrogen in?

OK...OK..so now it takes 50 years to break even on your solar/hydrogen
system. You better start right away then and don't borrow any money to do it
or you may never break even.
OK Here's the million dollar question. How do I make a profit by paying
for conventional power? As far as I can see I'm losing money all the way.
And how much money will I be losing ten years from now, let alone 25 or 50?
We know what happened to the prices in the last ten years. What will happen
in the next ten?
I don't see that being factored into your argument.

Glenn Martin
 
G

Glenn Martin

Jan 1, 1970
0
As far as a total rework of appliances -- well, that simply isn't
necessary. It's common around here to buy appliances that will run on
propane or methane depending on the size of the orifice that is
installed. To run all the appliances in our house on hydrogen, we would
need to change some piping, and some orifices (known by some as 'jets').
It wouldn't be trivial, but it wouldn't be much harder than changing
from propane to natural gas. It is certainly far from being a 'total
rework'.

I am wondering what you are talking about with colorants and odorants.
Why do you want to color the hydrogen gas? Also, why not use the same
odorant that we currently use with propane and methane?


Ray Drouillard
Colourants and odorants are to allow easy detection of leaks. Natural gas
is odorless. It has a rotten egg-like smell added so leaks can be instantly
noticed. There are cases every year where someone who's lost the sense of
smell dies in a gas explosion.
Mind you, since staic discharge is enough to set off hydrogen, no way do I
want it in my house. The end of the garden is fine for me though.

Glenn Martin
 
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Glenn Martin

Jan 1, 1970
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Don Lancaster said:
Exergy is a measure of the thermodynamically reversibly recoverable
energy fraction.

Don, what does this mean? What is an enrgy fraction? What does "reversibly
recoverable" mean?

Why do you apply "amortization"; a financial term, to physical measurements
of energy conversion efficiency?

Glenn Martin
 
D

Don Lancaster

Jan 1, 1970
0
Dan said:
I've recently, and in the past repeatedly, posted them. I guess I'll
have to put it in a webpage. (like so many page I'd like to get done.)


5% of the heating value of coal gets to the wheels of a vehicle via
hydrogen.

Best, Dan.

Before amortization.

Less than zero of the heating value of coal gets to the wheels of a
vehicle via hydrogen when full burden accounted for under today's
economics.

--
Many thanks,

Don Lancaster
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
voice: (928)428-4073 email: [email protected]

Please visit my GURU's LAIR web site at http://www.tinaja.com
 
D

Don Lancaster

Jan 1, 1970
0
Dan said:
Latch on to what you want 'to hear', or, do some research and quit trolling.

Best, Dan.

It is interesting to try and buy an electrolysizer.
Chances are overwhelming they will not even tell you how much they cost.

--
Many thanks,

Don Lancaster
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
voice: (928)428-4073 email: [email protected]

Please visit my GURU's LAIR web site at http://www.tinaja.com
 
D

Don Lancaster

Jan 1, 1970
0
OK Here's the million dollar question. How do I make a profit by paying
for conventional power?
Glenn Martin

Obviously, you make a profit by paying LESS for conventional power than
you do for solar pv and similar energy sink alternates.

--
Many thanks,

Don Lancaster
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
voice: (928)428-4073 email: [email protected]

Please visit my GURU's LAIR web site at http://www.tinaja.com
 
D

Don Lancaster

Jan 1, 1970
0
william said:
I've already said do
the math without calculating the time value of money, the point still
stands.

The time value of the money IS the math.
Everything else is totally bogus.

--
Many thanks,

Don Lancaster
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
voice: (928)428-4073 email: [email protected]

Please visit my GURU's LAIR web site at http://www.tinaja.com
 
D

Don Lancaster

Jan 1, 1970
0
Glenn said:
Colourants and odorants are to allow easy detection of leaks. Natural gas
is odorless. It has a rotten egg-like smell added so leaks can be instantly
noticed. There are cases every year where someone who's lost the sense of
smell dies in a gas explosion.
Mind you, since staic discharge is enough to set off hydrogen, no way do I
want it in my house. The end of the garden is fine for me though.

Glenn Martin

You must have a very large garden.
The DOT Orange Book recommends 2600 feet from any occupied structure.
Daytime, nowind.

--
Many thanks,

Don Lancaster
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
voice: (928)428-4073 email: [email protected]

Please visit my GURU's LAIR web site at http://www.tinaja.com
 
D

Don Lancaster

Jan 1, 1970
0
Glenn said:
Don, what does this mean? What is an enrgy fraction? What does "reversibly
recoverable" mean?

Why do you apply "amortization"; a financial term, to physical measurements
of energy conversion efficiency?

Glenn Martin

This is all carefully explained in
http://www.tinaja.com/glib/energfun.pdf
Or http://www.tinaja.com/glib/hack64.pdf for a thermodynamics intro.

A reversible thermodynamic process kicks off zero unrecoverable low
grade heat.
If you go electricity ---> room heat ----> electricity, you get
virtually none of your electricity back because Carnot's Law prevents
even a theoretical low delta-T recovery of more than a percent or two.
Going electricity ---> hydrogen ---> electricity is considerably WORSE
than this today.

Exergy is the measure of this fraction and thus the energy value. If you
can convert the present energy form into another and back again with
most of it left, you have high exergy. If not, you have low exergy or
(in the case of hydrogen) negative exergy.

Exergy is also easily quantifiable. The Gibbs Free Energy is one
pre-amortization measure that applies to certain classes of fuels.

The amortization directly enters into the recoverable energy fraction
you can get back.
If you get back two cents worth of electricity and the interest on the
system is three cents, you have a net energy sink and are destroying
gasoline.

The equivalance between dollars and energy can be observed by the large
sign out front that says UNLEADED $1.97. Ultimately all of economics is
dictated by the underlying net energy sources.

Yes, if the price of gas goes up, the exergy of hydrogen goes down.
That is the beauty of exergy. It tracks the true costs of reversible
fraction recovery.

See http://www.fes.uwaterloo.ca/u/jjkay/pubs/exergy/ for an independent
tutorial.

There are also something like 17,000 Google hits on exergy.

Exergy is THE measure of the competitive viability of an energy delivery
system.

And positively, emphatically, and absolutely GUARANTEES us that
electrolysis from high value grid or pv sources for bulk hydrogen energy
flat out ain't gonna happen.

--
Many thanks,

Don Lancaster
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
voice: (928)428-4073 email: [email protected]

Please visit my GURU's LAIR web site at http://www.tinaja.com
 
D

Dan Bloomquist

Jan 1, 1970
0
Ray said:
I briefly looked through energyforfun.pdf, and it looked interesting --
but I didn't find the actual efficiency of electrolysis. In any case,
multiply that by about 0.65 (the efficiency of a decent fuel cell)...

Graham has more than once searched the available PEM efficiency. The
very best he could find was in the low 30% range. Once again, our
majority source of electrical energy is coal at 30% heating value. So
hydrogen in a vehicle is:

coal -> hydrogen -> wheels.

If you do the math, you find 5% of the heating value of that coal gets
to the wheels.
Ray Drouillard

Best, Dan.
 
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Ray Drouillard

Jan 1, 1970
0
Eric Gisin said:
You won't get more than 40% back, less if compact storage required. Worse than
any battery.


40% Is a whole lot better than the "less than none" that Don Lancaster
keeps quoting. As a matter of fact, I'm beginning to believe that he
has the whole spiel stuck in a text file for quick addition to his
prose.

I still want more details about that 40%. I'm hearing figures anywhere
between 60% and 90% for both electrolysis and fuel cells. Where is the
hard data? Yes, I can google until I'm blue in the face and crippled
from carpel tunnels, but some of those quoting the efficiencies ought to
have real data somewhere.

If we have electrolysis going at 80% efficiency, and a 70% efficient
fuel cell (just to throw in some reasonable numbers). you have a total
efficiency of better than 50% (allowing for some modest storage losses).

If you want to compress the hydrogen to store it, and if the energy cost
of that is significant, you can recover some of the energy by using an
'air engine' to decompress the hydrogen before it is fed into the fuel
cell.

Also, in a solar energy system, you are going to be getting more energy
in the summer than in the winter. That means that you will be using the
fuel cell in the winter if your solar array is sized such that you need
to store power in the summer for use in the winter. In that case, the
heat that is generated by the fuel cell can be used to heat the house.
In that way, you can use 100% of the energy that you have stored in your
hydrogen tanks. Any inefficiencies end up heating the house, or maybe
even cooking the meals (depending on how 'retentive' you want to be when
designing the system)

Certainly, the cost of photovoltaics makes the system uneconomical now.
But, this is rec.arts.sf.science, so speculation of future advances in
the art are definitely on topic.

If I could go out and buy a bunch of plastic sheeting that converts
light into electricity with an efficiency of about 8% for a few cents a
watt, what would I do with it? Putting it on the roof would be a good
start. Storing power in batteries short-term for use at night would
also be a good idea. In fact, I can save on the cost of an inverter if
I use a bunch of batteries in series and store it at 180V, then just use
some MOSFETs to generate a pseudo sine wave output -- no up-converting
switching regulator, no muss, no fuss.

Of course, if the photovoltaics are that cheap, it makes more sense to
hang enough of it to generate all my needs on the shortest day of the
winter than to pay a bunch of money for a fancy fuel cell.


Ray Drouillard
 
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Ray Drouillard

Jan 1, 1970
0
Don Lancaster said:
You won't even get ZERO percent back.
You will get less than zero back under today's economics when full cost
accounted.

http://www.tinaja.com/h2gas01.asp

Why do we keep switching from economic to engineering considerations and
back?

Anyhow, there is no question that it is uneconomic to try to get energy
from solar cells -- even if you can use the energy right away. The
things are just too expensive. They are useful for things like solar
calculators and some areas where you can't tap into the grid -- like the
ISS, for instance.

The "less than zero" statement I keep seeing does not have the word
"economic" coupled to it. Now that I know that you mean "economic", I
have to agree. Photovoltaics are not economical except in certain
limited instances (like solar calculators, the ISS, or a cottage out in
the middle of nowhere).

Now, if you already have the photovoltaics installed (your fairy
godmother gave them to you and installed them), and you have excess
power, what are you going to do with it? That sets up another set of
assumptions when you do your economic calculations.

Let's say you decide to be a hermit and get that off-grid cottage in the
middle of nowhere. Suddenly, you can't compare your power cost with
that of grid power. In that case, you have yet another set of
assumptions for your economic calculations.

Just saying "less than none" on a generic basis without publishing your
assumptions isn't really going to work.


Ray Drouillard
 
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Ray Drouillard

Jan 1, 1970
0
Dan Bloomquist said:
Quit yapping. Where are you going to get the hydrogen?


Best, Dan.

That's discussed elsewhere in the thread.
 

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