Jeff writes:

But the spec sheet says "Average current consumption for 12 VDC
systems over 24-hour period." This is the number of interest to most
boaters, and the proper measure is Amp-Hours.

No it isn't. Current is measured in amps. Amp-hours are not a measure
of current. Nothing could be simpler, and nothing more can really be
debated about it. This is not an oversight, it shows the author is a
fraud or a fool.

While R-134a is safer than other refrigerants it is still illegal to
vent and difficult to handle properly. Its toxic and corrosive, and
anyone who has had a larger refrigeration system serviced understands
from the amount of gear the technician hauled down to the boat that
these are not trivial procedures. A CO2 system, on the other hand,
can be vented freely, and recharged with a simple cartridge. No
license or special training is required. If this does not look like a
significant advantage to you, then you should not be posting in a
"cruising" forum.

You are in your typical error about the "simple cartridge" as a
comparative advantage. A cartridge for CO2 at 1000 psi is not "simple"
in comparison to ordinary refrigerants at 100 psi. Whatever
"simplicity" advantage you are imagining, it inheres more in the usual
refrigerants. The fact that it is *harder* to store CO2 in a cartridge,
yet this is claimed as an "advantage", just further shows the stupidity
and/or deceit of the claims.

"Vented freely" is a political, not a technical advantage.

CO2 is lousy refrigerant for all but a few unusual applications, because
of its material properties, such as high saturation pressure, and low
critical temperature. It does not fit ordinary refrigeration
applications, and it cannot be engineered to do so. It only "works" as
a political force-fit, like when Coca-Cola wants PR for the Athens
Olympics.

But you didn't base your argument on weighing pros and cons, you
claimed that CO2 refrigeration was impossible, a hoax, and likened it
to "perpetual motion machines." Thank you for admitting you were
wrong, however obliquely.

No, I said that this "tropikool" gadget amounts to perpetual motion
claims, and that CO2 efficiency was a hoax, that efficiency (relative
to, say, R-134a) was impossible. That politicians let you vent CO2 but
not R-134a says nothing about their respective material properties as a
refrigerant. I never said CO2 refrigeration was impossible in
principle, just impossible that it would be practical in ordinary
applications.

You might as well claim that a steam engine is better than gasoline
internal combustion, because we can fuel it with grass clippings instead
of that expensive petroleum. Yes, it is possible to get steam power
from grass clippings, but it is impossible that it could work better
than a gasoline engine.

Now I will admit I was wrong, in that if a politician holds a gun to my
head and insists that CO2 is all you seem to be claiming, then yes, CO2
is just great. Since we still haven't reached quite that point, I
regret I must maintain that the OP points to a product that is a phony
based on either fraud or foolishness.

Richard J Kinch wrote:
Jeff writes:


But the spec sheet says "Average current consumption for 12 VDC
systems over 24-hour period." This is the number of interest to most
boaters, and the proper measure is Amp-Hours.


No it isn't. Current is measured in amps. Amp-hours are not a measure
of current. Nothing could be simpler, and nothing more can really be
debated about it. This is not an oversight, it shows the author is a
fraud or a fool.

Yes current is measured in amps. But to be useful you need another
measurement, time. That gives amp hours. Battery capacity is rated in
amp hours, usually at a 20 amp rate. If I want to know what size
batteries I need to supply my house load I measure the current used by
each device, i.e. lights, fans, reffer, etc and determine the
approximate time used by each device and compute total amp hours load
over a 12 or 24 hour period. Multiply the amp hour load by two and use
that size battery. So while you are correct that the measurement of
current is amps, if a manufacturer list a spec of 54 amp hours usage in
24 hours it tells me a lot more than just 4 amps compressor draw.
krj


While R-134a is safer than other refrigerants it is still illegal to
vent and difficult to handle properly. Its toxic and corrosive, and
anyone who has had a larger refrigeration system serviced understands
from the amount of gear the technician hauled down to the boat that
these are not trivial procedures. A CO2 system, on the other hand,
can be vented freely, and recharged with a simple cartridge. No
license or special training is required. If this does not look like a
significant advantage to you, then you should not be posting in a
"cruising" forum.


You are in your typical error about the "simple cartridge" as a
comparative advantage. A cartridge for CO2 at 1000 psi is not "simple"
in comparison to ordinary refrigerants at 100 psi. Whatever
"simplicity" advantage you are imagining, it inheres more in the usual
refrigerants. The fact that it is *harder* to store CO2 in a cartridge,
yet this is claimed as an "advantage", just further shows the stupidity
and/or deceit of the claims.

"Vented freely" is a political, not a technical advantage.

CO2 is lousy refrigerant for all but a few unusual applications, because
of its material properties, such as high saturation pressure, and low
critical temperature. It does not fit ordinary refrigeration
applications, and it cannot be engineered to do so. It only "works" as
a political force-fit, like when Coca-Cola wants PR for the Athens
Olympics.


But you didn't base your argument on weighing pros and cons, you
claimed that CO2 refrigeration was impossible, a hoax, and likened it
to "perpetual motion machines." Thank you for admitting you were
wrong, however obliquely.


No, I said that this "tropikool" gadget amounts to perpetual motion
claims, and that CO2 efficiency was a hoax, that efficiency (relative
to, say, R-134a) was impossible. That politicians let you vent CO2 but
not R-134a says nothing about their respective material properties as a
refrigerant. I never said CO2 refrigeration was impossible in
principle, just impossible that it would be practical in ordinary
applications.

You might as well claim that a steam engine is better than gasoline
internal combustion, because we can fuel it with grass clippings instead
of that expensive petroleum. Yes, it is possible to get steam power
from grass clippings, but it is impossible that it could work better
than a gasoline engine.

Now I will admit I was wrong, in that if a politician holds a gun to my
head and insists that CO2 is all you seem to be claiming, then yes, CO2
is just great. Since we still haven't reached quite that point, I
regret I must maintain that the OP points to a product that is a phony
based on either fraud or foolishness.

Richard J Kinch wrote:

Jeff writes:


But the spec sheet says "Average current consumption for 12 VDC
systems over 24-hour period." This is the number of interest to most
boaters, and the proper measure is Amp-Hours.



No it isn't. Current is measured in amps. Amp-hours are not a
measure of current. Nothing could be simpler, and nothing more can
really be debated about it. This is not an oversight, it shows the
author is a fraud or a fool.

Yes current is measured in amps. But to be useful you need another
measurement, time. That gives amp hours. Battery capacity is rated in
amp hours, usually at a 20 amp rate. If I want to know what size
batteries I need to supply my house load I measure the current used by
each device, i.e. lights, fans, reffer, etc and determine the
approximate time used by each device and compute total amp hours load
over a 12 or 24 hour period. Multiply the amp hour load by two and use
that size battery. So while you are correct that the measurement of
current is amps, if a manufacturer list a spec of 54 amp hours usage
in 24 hours it tells me a lot more than just 4 amps compressor draw.
krj

Ya know, this thread keeps gettin sillier and sillier. Amp-hours, if
anyone cares to look it up instead of just flappin, is a measurement of
current. And I defy anyone, including Mr. Kinch, to find a way for
current to flow without time. If current was without time, it could not
possibly *be* current. It would then be reduced to "...potential for
current to flow, which when flowing would be measured in amp-hours..."
Current is a verb, it defines an action. Without the action, there's no
flow. Without the flow there's no "amps", which is always measured
against a unit of time - the convention being hours (notice I said
'convention'- you could use any time measurement, days, U-seconds,
etc.). It cannot be measured without time - ever. Therefore, "amps" by
itself, does not describe anything. You could say there is a measurement
of an *instantaneous current* but that would still be just a snapshot of
the presently measured current-against-time. Amp-hours is and has been
the correct term because a "1 amp" device is defined by convention as a
device that passes a current of 1 amp during the course of an hour. The
term "1 amp" is simply a contraction for "device that passes 1 amp of
current during the period of one hour" Now, isn't that a mouthful?
Jeesh! The engineers and tech's of old used to actually *say*
"amp-hours" when describing current, and all my old electronics
textbooks use that term exclusively.

So if Mr. Kinch wants to call all my electronics professors frauds or
fools, so be it. But then I'll challenge him to come over and put his
instruments where his mouth is and show us all how he manages to measure
"amps" without time for the electrons to flow.

Or was that holes flowing... hmmm...

Sailaway wrote:
....

Ya know, this thread keeps gettin sillier and sillier. Amp-hours, if
anyone cares to look it up instead of just flappin, is a measurement of
current. And I defy anyone, including Mr. Kinch, to find a way for
current to flow without time. If current was without time, it could not
possibly *be* current. It would then be reduced to "...potential for
current to flow, which when flowing would be measured in amp-hours..."
Current is a verb, it defines an action. Without the action, there's no
flow. Without the flow there's no "amps", which is always measured
against a unit of time - the convention being hours (notice I said
'convention'- you could use any time measurement, days, U-seconds,
etc.). It cannot be measured without time - ever. Therefore, "amps" by
itself, does not describe anything. You could say there is a measurement
of an *instantaneous current* but that would still be just a snapshot of
the presently measured current-against-time. Amp-hours is and has been
the correct term because a "1 amp" device is defined by convention as a
device that passes a current of 1 amp during the course of an hour. The
term "1 amp" is simply a contraction for "device that passes 1 amp of
current during the period of one hour" Now, isn't that a mouthful?
Jeesh! The engineers and tech's of old used to actually *say*
"amp-hours" when describing current, and all my old electronics
textbooks use that term exclusively.

Sorry, I don'[t think you have it quite right. "Current" is an
instantaneous rate of charge flow. Although formally defined in terms
of forces in wires, it is better understood as a change in charge, as
in coulombs/second. Since Coulombs can be thought of as a number of
electrons (6.24E+18), Amps are "electrons per second" ignoring the
constant factor. Amps-hours thus represent a number of electrons.
However, the spec sheet said "Average current consumption for 12 VDC
systems over 24-hour period" which is "Amp-hours/day" - for some
reason Kinch keeps ignoring this even though is is clearly stated.
This is measure of charge flow, simply scaled up by 24 from amperes.


So if Mr. Kinch wants to call all my electronics professors frauds or
fools, so be it. But then I'll challenge him to come over and put his
instruments where his mouth is and show us all how he manages to measure
"amps" without time for the electrons to flow.

Measuring something is different from stating its instantaneous
property. Velocity is stated for a moment in time, but is real hard
to measure without considering a change in position over time, or by
using some other technique that considers time.



Or was that holes flowing... hmmm...

Jeff said:
Sorry, I don'[t think you have it quite right. "Current" is an
instantaneous rate of charge flow. Although formally defined in terms
of forces in wires, it is better understood as a change in charge, as
in coulombs/second. Since Coulombs can be thought of as a number of
electrons (6.24E+18), Amps are "electrons per second" ignoring the
constant factor. Amps-hours thus represent a number of electrons.
However, the spec sheet said "Average current consumption for 12 VDC
systems over 24-hour period" which is "Amp-hours/day" - for some
reason Kinch keeps ignoring this even though is is clearly stated. This
is measure of charge flow, simply scaled up by 24 from amperes.

snip


Measuring something is different from stating its instantaneous
property. Velocity is stated for a moment in time, but is real hard
to measure without considering a change in position over time, or by
using some other technique that considers time.


You've said (pretty obliquely) some of the same thing ("electrons per
second"), and I agree with your statement about measurement being
different than describing an instantaneous property.
Current is flow. Flow is not stagnant. Flow cannot be anything else
but flow. For flow to happen in this case, electrons have to move. When
they move, it is called "current". Think of a river - can "current" flow
without movement? You can describe the amount of electrons existing in a
conductor at any one instant in time as a snapshot of an amount of
electrons existing in a conductor, but that amount is the result of the
electrons having flowed through that part of the conductor during some
amount of time however small or large. Just measuring or calculating the
number of electrons present in a conductor is not a measure of current
in and of itself, because current is a measure or calculation of the
number of electrons having flowed through a conductor during a given
specific amount of time.

What you are describing is the *rate* of flow as a snapshot of some
instant in time. But to get that snapshot of the rate of flow, you must
first have current, measured in amp-hours. What you alluding to is not a
measurement, it is a description of a rate of measurement at one
instant. Mr. Kinch talked about a piece of equipment should be rated at
(x) amps, but the term *amps* is in this case a *new terminology*
contraction for amp-hours, or it wouldn't make any sense. We all assume,
consciously or unconsciously, when reading a current rating listed on
any equipment when listed as *amps* to actually be amps-per-hour (the
*rate*) which is the current standard convention.
The time used for your measurement, however, is irrelevant, it is just a
way to determine how many electrons have flowed through the conductor
during that time. So if you used average current over one hour, or one
day, or one year, etc., you still have the same exact same type of
measurement; amps-per-whatever. But average measurement does not
describe what the flow is at any one instant in time, which is what you
were alluding to.
Electrical "pressure" is the old terminology for voltage, described as
"potential". This is not current, but influences current as described by
ohm's law.
Charge is a different entity entirely and is not current.
Velocity is not current, but can influence current. The term can also
seem confusing. If you have a large diameter pipe and have 1 gallon per
hour of water flowing through it, and you have a very small diameter
pipe and have 1 gallon per hour flowing through it you will have two
very different velocities. But if current is the measurement of
units-of-something-per-time, then the *current* is the same in both
pipes, although the *pressure* will necessarily be different (just like
ohm's law). But if the velocity of current, that is, if electrons are
limited in the actual speed each can flow through a given conductor
regardless of pressure (IE: speed of light in a perfect conductor), then
the number of electrons that can flow through a conductor in a given
time is limited at least by the size of the conductor, regardless of the
pressure (voltage). So *velocity* can be an imprecise term to describe
current if you label the amount of current flow as speed of flow (speed
of each electron moving), rather than the total number of
electrons-per-unit-of-time. Of course, exceeding a conductor's ability
to pass a certain number of electrons in a given amount of time will
result in excessive heat which may result in damage, hence the need to
describe a conductor's ability to handle a specific *rate* of current
flow. Most conductors will destruct due to heat before actually
exceeding its max rate of flow of electrons. That is why cooling a
conductor allows more current to be applied through it before self
destructing.
When measuring current with a meter, all U.S. meters that I have seen
and used measure in amps per hour averaged. Meters cannot take a
snapshot in time, because no matter how short the cutoff, it is still time.
If you'd like, you are invited over to look at any number of textbooks
I have (several lockers full) that will describe it for you more
eloquently and completely than I will here. Although my textbooks are
written in the "old" language of electronics - you know; amp-hours,
cycles per second, etc.

Sailaway writes:

Amp-hours, if
anyone cares to look it up instead of just flappin, is a measurement of
current.

No. Amp-hours is a unit of charge. Not current.

Your post is a schizoid rant of physical gibberish.

So if Mr. Kinch wants to call all my electronics professors frauds or
fools, so be it.

If you are claiming to be consulting authorities, I suspect the problem is
your muddled misunderstanding of them.

That's Dr, not Mr, by the way, when it comes to engineering and physics.

Mr. Kinch foamed thusly:
Your post is a schizoid rant of physical gibberish.

Ya caught me!

I've always believed if you can't dazzle 'em with brilliance, then
baffle 'em with bull****.

Have a nice day.

Richard J Kinch wrote:
Jeff writes:

But the spec sheet says "Average current consumption for 12 VDC
systems over 24-hour period." This is the number of interest to most
boaters, and the proper measure is Amp-Hours.

No it isn't. Current is measured in amps. Amp-hours are not a measure
of current. Nothing could be simpler, and nothing more can really be
debated about it. This is not an oversight, it shows the author is a
fraud or a fool.

Time to put you out of your misery, Richard. "Amp-hours per day" is a
measure of current, just the same as Amps. Think about it. Do the
dimensional analysis - hours per day, that's just a conversion factor,
and what's left? Amps!

Anyone who has a fridge on a boat knows that the instantaneous current
in not important, its the average. And the most useful way to state
that is in Amp-hours per day, a perfectly valid way to measure current.

This is not an oversight, it simply means you're the fraud or fool.




While R-134a is safer than other refrigerants it is still illegal to
vent and difficult to handle properly. Its toxic and corrosive, and
anyone who has had a larger refrigeration system serviced understands
from the amount of gear the technician hauled down to the boat that
these are not trivial procedures. A CO2 system, on the other hand,
can be vented freely, and recharged with a simple cartridge. No
license or special training is required. If this does not look like a
significant advantage to you, then you should not be posting in a
"cruising" forum.


You are in your typical error about the "simple cartridge" as a
comparative advantage. A cartridge for CO2 at 1000 psi is not "simple"
in comparison to ordinary refrigerants at 100 psi. Whatever
"simplicity" advantage you are imagining, it inheres more in the usual
refrigerants. The fact that it is *harder* to store CO2 in a cartridge,
yet this is claimed as an "advantage", just further shows the stupidity
and/or deceit of the claims.

In the manual it says that PFD inflation cartridges between 33 and 37
grams may be used. Don't you feel like a real idiot just now?


"Vented freely" is a political, not a technical advantage.

Its also a legal issue. And some of us don't want to vent a gas that's
1300 times worse than CO2 for global warming.


CO2 is lousy refrigerant for all but a few unusual applications, because
of its material properties, such as high saturation pressure, and low
critical temperature. It does not fit ordinary refrigeration
applications, and it cannot be engineered to do so. It only "works" as
a political force-fit, like when Coca-Cola wants PR for the Athens
Olympics.

Political or not, r-12 was phased out and r-134a will likely be phased
out. In spite of your claims, there seem to be lots of sources that say
the efficiency is not a big problem.



But you didn't base your argument on weighing pros and cons, you
claimed that CO2 refrigeration was impossible, a hoax, and likened it
to "perpetual motion machines." Thank you for admitting you were
wrong, however obliquely.


No, I said that this "tropikool" gadget amounts to perpetual motion
claims, and that CO2 efficiency was a hoax, that efficiency (relative
to, say, R-134a) was impossible. That politicians let you vent CO2 but
not R-134a says nothing about their respective material properties as a
refrigerant.

Actually, it has more do do with the environmental issue.

I never said CO2 refrigeration was impossible in
principle, just impossible that it would be practical in ordinary
applications.

Using terms like "hoax" "fraud" and "perpetual motion" is tantamount to
claiming its impossible. And given that there are a number of systems
in use, including refrigeration and automobile A/C, it would appear that
your assertion is incorrect. In fact, in my limited research I found a
number of studies that implied there was no major efficiency issue, that
even in the worst cases co2 was within 10%-20% of r134a, and in some
configurations it was more efficient. Small boat systems aren't really
that efficient, so there's plenty of room for improvement.



You might as well claim that a steam engine is better than gasoline
internal combustion, because we can fuel it with grass clippings instead
of that expensive petroleum. Yes, it is possible to get steam power
from grass clippings, but it is impossible that it could work better
than a gasoline engine.

That's a pretty poor analogy - its more like claiming hybrid cars can
work; they seemed a bit silly when first proposed, now they make a bit
more sense. (I'm sure you'll now claim they're a hoax ...)


Now I will admit I was wrong, in that if a politician holds a gun to my
head and insists that CO2 is all you seem to be claiming, then yes, CO2
is just great.

I have not made any claim. I am curious to see how it works out. I
don't know if it is more efficient than the alternatives, but to claim
its a "hoax" and "fraud" without any evidence seems reprehensible.

Since we still haven't reached quite that point, I
regret I must maintain that the OP points to a product that is a phony
based on either fraud or foolishness.

And I must maintain that your close minded approach marks you as a
foolish fraud.

Jeff writes:

"Amp-hours per day" is a measure of current, just the same as Amps.

Specifying "hours per day" is meaningful? You're just compounding the
absurdity.

PFD inflation cartridges between 33 and 37 grams may be used.

Which as containers are inferior (cost, weight, capacity) to a $7 can of
R-134a, because CO2 is inherently harder to contain.

And some of us don't want to vent a gas ...

You may be of that political view, but it doesn't change the dismal
physics and economics of CO2 as a refrigerant. You may force CO2
refrigeration to replace R-134a, but don't pretend that it works better
or doesn't cost more.

Using terms like "hoax" "fraud" and "perpetual motion" is tantamount
to claiming its impossible.

I said the efficiency claims were not credible and foolishly misstated.
Don't twist that into anything more. Perpetual motion machines are
impossible, not all machines that produce motion.

[hybrid cars] seemed a bit silly when first proposed, now they make
a bit more sense. (I'm sure you'll now claim they're a hoax ...)

They're a hoax in claiming or implying a better lifetime cost per mile.

I am curious to see how it works out.

Sure, I am too. And having experienced the 1970s as an engineer, I am
confident I know how it will work out. About as well as synthetic
fuels.

... your close minded approach ...

Be closed-minded about errors in technology. These are not unscientific
opinions or tastes. Those of us who do genuine engineering research and
devlopment for a living don't call it "closed-minded", we call it "not
beating a dead horse". CO2 is a dead horse, it was killed in the 1930s,
and resurrected and killed all over again in the 1980s with the CFC
mania.

There is no virtue in being open-minded about stuff like CO2
refrigeration that can't possibly work well. Look at it in the lab,
learn what you can about it, but don't pretend that somehow vacuous
optimism will someday yield anything practical, if we just keep
tinkering with it.

Richard J Kinch wrote:
Jeff writes:


"Amp-hours per day" is a measure of current, just the same as Amps.


Specifying "hours per day" is meaningful? You're just compounding the
absurdity.

No, you're simply showing that you actually have no real training or
experience in engineering. If you did, you would understand that
"amp-hours per day" is a measure of current.

"Hours per day" is simply a non-dimensional constant, normally given
as 24. Thus, what remains is a measure of current.

Why don't you go down to your community college and enroll in Physics
101, you might learn something.

Anyone curious about "dimensional analysis" could google it or look at:
http://www.physics.uoguelph.ca/tutorials/dimanaly/


PFD inflation cartridges between 33 and 37 grams may be used.

Which as containers are inferior (cost, weight, capacity) to a $7 can of
R-134a, because CO2 is inherently harder to contain.


Whatever you say Richard, I'm sure that the difficulty in making CO2
PFD cartridges will be the ultimate downfall of CO2 refrigeration.

And while it might be fairly simple to charge up a leaky auto A/C
circuit with a can of r134a, properly recovering and recharging a
system requires about $500 of gear and a license. Fixing a simple
leak in a marine system costs at least a few hundred dollars, and
can't be done by the average cruiser.

And some of us don't want to vent a gas ...

You may be of that political view,

So are you claiming that global warming and losing the ozone layer are
just a "political view"? Are you claiming that we should feel free to
vent r134a because the restrictions are just "political"? Or are you
confessing that you flaunt the law in spite of the rather stiff fines?

but it doesn't change the dismal
physics and economics of CO2 as a refrigerant. You may force CO2
refrigeration to replace R-134a, but don't pretend that it works better
or doesn't cost more.

On average perhaps it doesn't, although even the pro-R134a association
only claimed CO2 was slightly less efficient. However, small
systems are very inefficient, so there's no reason why this system
might not equal or better the competition. Further, having only 2
moving parts and user serviceability are a major advantage. Being
skeptical about a product doesn't give you the right to label it as a
"hoax" or "fraud."


Using terms like "hoax" "fraud" and "perpetual motion" is tantamount
to claiming its impossible.


I said the efficiency claims were not credible and foolishly misstated.
Don't twist that into anything more.

Your first post included "Idiotic nonsense" and "either a fraud, or a
nutcase"

You said "My point is, the spec sheet uses gibberish" when in fact the
spec sheet uses the proper terminology, properly labeled. You are
simple not sufficiently well-versed in engineering to understand it.

Perpetual motion machines are
impossible, not all machines that produce motion.

You referred to this as "It is a mad inventor's perpetual motion machine"

Why are you trying to deny what you said just yesterday?



[hybrid cars] seemed a bit silly when first proposed, now they make
a bit more sense. (I'm sure you'll now claim they're a hoax ...)


They're a hoax in claiming or implying a better lifetime cost per mile.

These "claims" are only in your imagination. I believe the economy
and cost of the vehicles are public information. As with much new
technology, early adopters pay a premium for the privilege. However,
the price is declining steadily, and the fuel cost is rising, so its
possible that hybrids will actually have a better lifetime cost per
mile in a few years. Actually, just going by the MSRP and EPA mileage
its getting close to break even now.

I am curious to see how it works out.

Sure, I am too. And having experienced the 1970s as an engineer, I am
confident I know how it will work out. About as well as synthetic
fuels.

Syn fuels are predicted to be roughly 10% of domestic oil production
in 25 years; perhaps even double that if the high price stays with us.
In this "high price" model, a quarter of the coal mined would go to
syn fuel. That would fund my retirement.

This is from recent DOE testimony before a Senate committee. I
believe (though I'm not sure) that this assumes there is no subsidy
for syn fuel, because the price of oil is above the cutoff.


... your close minded approach ...

Be closed-minded about errors in technology. These are not unscientific
opinions or tastes. Those of us who do genuine engineering research and
devlopment for a living ...

You really have a problem convincing anyone that you ever did any
engineering, given that you don't know what dimensional analysis is.
If you had, you would understand that "amp-hours per day" is a measure
of current.