Re: Also I tried to be open-minded, I tried splitting H2O tonight with 12V 120 amps,

On Dec 26, 4:08 am, Don Lancaster <d...@xxxxxxxxxx> wrote:
Robert Adsett wrote:
In article <a35e7f3f-2451-4afc-8339-
2a9afcb39...@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,  says...

On Dec 25, 8:04 am, Don Lancaster <d...@xxxxxxxxxx> wrote:

RadicalModerate wrote:

And for motor vehicle use, replacing gasoline and diesel fuel with
solar-generated hydrogen would pay big benefits in increased air quality
for our cities.

Enormously unlikley.
Also not even wrong.

There ALWAYS will be more intelligent things to do with high exregy
electricity than convert it into low grade hydrogn.

If all else fails, smelt some aluminum or refine some copper.
Or use pumped storage.

You talk elegantly of exergy - which doesn't have a definition in any
of the popular online dictionaries.  

Perhaps you need to widen your search a touch.  This pops up fairly
readily.

http://en.wikipedia.org/wiki/Exergy

I don't remember the term from any of my statistical thermodynamics
courses but it appears to be a real enough derived term

Robert

Exergy is a measure of the quality and thus the value of energy in its
present form. It is basically entropy with an economic value focus.

Exergy answers the question "How much is this stuff worth in its present
form?"


Could you give us a completely worked example, or a pointer to a
completely worked example?


An unstruck match has very high exergy; a slightly warmer room has very
little.

Why? A cold hospital room may have tremendous value to a feverish
patient and also a large cost to the hospital if poorly insulated and
rather large Is it worth it? Depends on how much the patient is
willing to pay for comfort and health in that moment. An unstruck
match may save a home from burning down. So, your generalities and
hand-waving aren't really of the nature of a precise definition.

I mean, I can say that kinetic energy equals one half mass times
velocity squared. That's a PRECISE definition of kinetic energy. I
can even work an example. a kilogram of mass moving at 10 meters per
second has 50 joules of kinetic energy. Talking about matches and
warm rooms and their relative value.

You have YET to propose a PRECISE definition that I would call
SCIENTIFIC.

Electricity is just about the highest exergy stuff around;

Depends on the details. Low voltage DC electricity whose efficient
production level varies with lighting conditions can't be as valuable
as AC electricity available on demand, if you want to keep things cold
in your freezer.

unstored
hydrogen gas is among the lowest.

What the hell is unstored hydrogen gas? Doesn't it depend on its
history? For example, hydrogen gas entering the fuel injection ports
during the intake cycle of a BMW Zentrum - is unstored - but strikes
me as being rather high value. What do you think? and more
importantly WHY!

You're still handwaving Don. You haven't impressed me yet with
anything that is REMOTELY SCIENTIFIC in your thought process. Just
words and handwaving.

The way you measure exergy is to convert the energy to a different form
and convert it back.

Why convert it back? and HOW? I take a gallon of gas and run it
through a 230 HP engine - and produce something like 30 MJ of
mechanical energy - driving over the Rocky Mountains at highway
speeds. Alright, HOW do I convert my speed and position BACK to
gasoline? I don't understand what you're saying.

DO YOU HAVE A PRECISE MATHEMATICAL WORKED EXAMPLE OF WHAT YOU ARE
TALKING ABOUT?

Then see how much you have left.

I have a gallon of gas at the bottom of the hill, and I'm cruising
along at highway speeds at the top of the hill, and the gallon of gas
is gone. What do I have left? How do I convert it back? Why?

Electricity to
hydrogen to electricity leaves you with less than zilch. Before
amortization.

Depends on the details. Variable intermittent DC power responding to
lighting conditions converted to chemical energy and then to AC power
on demand - could be of tremendous value. Like I said, I will tell
you EXACTLY how I compute things, you compute exergy and tell me
EXACTLY how its done. Let's go.

Here's mine

Solar panel - converts sunlight to DC electricity - drives a variable
load alkaline - aqueous - variable load - electrolyzer -

Solar --> DC Electricity 18%
DC Electricity --> Hydrogen gas 82%
Hydrogen Gas --> Transmission 80%
Burn Hydrogen --> Electricity 38%

Alright so a square kilometer of panels makes 180 MW under full
illumination in a spot, and in that spot produces on average 720 MWh
in a day. The cost of the array $12 million

These feed low cost variable load electrolyzers - that efficiently
load the panels based on lighting conditions. They produce a metrc
ton of hydrogen gas from 9 kL of water for every 50 MWh of DC
electricity they are provided from the solar panels. The cost of the
electrolyzers are $3 million. Attached to the aforementioned panels
they produce 14.4 metric tons of hydrogen in a day.

The hydrogen is compressed and transmitted by pipeline to a power
plant. The compressor and controls an all the rest use 2.4 metric
tons of the hydrogen transmitted in this way. The pipeline is 300 km
long and holds two days supply of hydrogen. It costs $30,000 per km -
a total of $9 million. This leaves 12.0 metric tons per day of
hydrogen gas delivered to a gas turbine adapted to burn hydrogen
instead of natural gas.

The turbine is 38% efficient at converting the 19.8 MW of heat energy
to 7.5 MW of AC electrical power sold on demand at a price of $0.15
per kWh. The cost of the gas turbine generator is $15 million.

For extra credit - compute the exergy of a square kilometer of 20
million year old biota producing a natural gas well to supply this
same generator.


Going from high value electricity (such as grid, pv, or wind) to low
value unstored hydrogen gas instantly and irreversibly destroys most of
the quality and thus most of the value of your energy.

I gave you a detailed example above - please show me where value is
destroyed. I am taking relatively low valued water and sunlight and
using $39 million worth of equipment and producing $27,000 worth of AC
electricity on demand every day. The hydrogen value is $9,600 per
day. The cost of capital at 8% for the $39 million is $8,500 per
day.


There ALWAYS will be more intelligent things to do with high value
electricity than destroying its value through electrolysis.

You are just waving your hands, work an example as I have above -
explain why Boeing for example is using electrolysis and onboard
storage of hydrogen AND oxygen to power aircraft. Why is that? Is
Boeing stupid? Or are you wrong?

http://www.boeing.com/news/frontiers/archive/2007/july/ts_sf06.pdf

Obviously Boeing isn't coming to the same conclusions as you are
regarding the low value of hydrogen.


The process
is very similar to 1:1 exchanging US dollars for Mexican Pesos.

So is burning gasoline to get mechanical energy - yet we do it because
we value the result.

Electrolysis for bulk energy hydrogen is ABSOLUTELY GUARANTEED to ain't
gonna happen.

Its already happening dog. As long ago as 1999 according to the NASA
report given below. Solar panels on wings of a large aircraft power
it through the night benefit of hydrogen stored on board made through
the day.

Regenerative fuel cells are used to turn windmills, pv panels, and
tidal power into baseload power. Regenerative fuel cells are used to
store energy as hydrogen and oxygen aboard aircraft so that it is
avaliable on demand.

http://www.gltrs.grc.nasa.gov/reports/1999/TM-1999-209429.pdf


By fundamental thermodynamics.

I have yet to see a worked thermodynamic problem. All I have heard is
a lot of generalities and hand waving. GIVE ME A PRECISE WORKED
EXAMPLE


Detailed analysis athttp://www.tinaja.com/glib/energfun.pdf

haha.. You cannot be serious Don. I looked at this web page. WHERE
IS THERE A WORKED EXAMPLE OF CALCULATING EXERGY OF A SYSTEM? There
isn't one. There isn't even a definition of exergy. So why are you
pointing to this as if it proves what you say about exergy? It is
totally silent on the subject.

As for what it DOES say... lol.

THIS WEB PAGE IS FULL OF LIES! It really is.

It says for example that embrittlement is an issue! Embrittlement was
cited as a reason for replacing pipes used in the very first
industrial hydrogen system in 1911 - that made ammonia fertilizers -
but that same report said that corrision in the wet German environment
was a greater problem for these very same pipes.

In 1958 when NASA created the first hydrogen supply chain to fuel
their hydrogen powered rockets, they cited embrittlement as a reason
for the higher than expected costs of the system. Embrittlement
isn't a show stopper - even then. Yet this web page - as just one
example of the lies it tells - suggests that embrittlement IS a show
stopper - which it isn't.

If that weren't enough the American Society of Mechanical Enginerers
adopted standards for hydrogen transmission and storage systems in
2006 - for example B31.12 - which relates the precise procedures for
creating pipelines and storage tanks for hydrogen that have 60 year
service lives - longer than any other tank or pipeline in service.
Yet here this web page is saying that embrittlement and permeation are
unsolved problems that make hydrogen fuel an impossibility.

Electrolysis fundamentals athttp://www.tinaja.com/glib/muse153.pdf

Lets look at real electrolysis units which even with low-cost aqueous
alkaline fuel cells under high pressure - operate at 65% combined
cycle efficiency.

Google shows 95,700 entries on exergy.

And 257,000 entries for face jesus clouds

The fact that Google shows 95,700 entries on exergy is not worth one
solid paper published by an engineering society. Do you happen to
have one of those? WITH A WORKED EXAMPLE?


A few of these are scholarly references of thousands or tens of
thousands of entries.

Give me ONE with a clear definition and a worked example - NO
HANDWAVING!


--
Many thanks,

Don Lancaster                          voice phone: (928)428-4073
Synergetics   3860 West First Street   Box 809 Thatcher, AZ 85552
rss:http://www.tinaja.com/whtnu.xml ; email: d...@xxxxxxxxxx

Please visit my GURU's LAIR web site athttp://www.tinaja.com- Hide quoted text -

- Show quoted text -

You're full of *** Don - the more you talk without saying anything of
substance - the clearer that becomes.
.