Refrigeration To Reduce Battery Size / Overall Energy Storag

>"Several patents cover PV on motor vehicles powering a small freezer >for instant cold ac."

I got into a van once that seemed to have instant cold air. It had sat for a while. The only thing I can think of is they shut off a valve and maintain the pressures in the refrigeration system. Automotive compressors have no problem starting under load. The house units have little starting torque so that would be impossible unless maybe you use a DC motor.

If you are a thermodynamics guy I have a question. It is one of those "Will this contraption work ?". I am pretty sure it would be impractical with today's technology, but is the principle sound ?

Air conditioning that simply uses air. You know how a diesel engine works. It is not friction that heats the air it is the fact that you are squeezing the same BTUs of heat into a much smaller space.

So, take a high pressure air compressor and pump up a heat exchanger (like a condenser but does not condense), stick in front of the car or whatever to cool and then just let the air out at whatever CFM you want for the cooling.

I understand the difficulty in getting a compressor that can deliver that much air at that pressure, but if you could would it work ? Or are there inefficiencies of which I am unaware that make it totally unworkable ?

Don't mean to hijack but the topic has to do with air conditioning so...

>"There should always be a cold non alcoholic drink at the ready >near the front seat."

Isn't there a luxury car out there somewhere with a cooled drink holder ? I know it is possible but I would not attempt to use a Peltier in it. You would have to water cool that or it would melt the pimp rest.

If such a thing were developed I had another harebrained idea for it. A gimbal type mechanism that makes a cover unnecessary. I used to take lunch with this guy we called Smitty who drove like a maniac. Like in my younger day at the tire shop the wear charts that told you if you had bad ball joints or whatever, mine were always "excessive speed on turns". Sometimes we ate in his car and even with the cover sometimes a drink would spill some. So I developed a technique of kinda holding it at the top and let the cup tilt to let it cancel out the Gforces produced. So I was thinking of some sort of mechanism that would do that.

Couple a device like that with a cooling system of some sort and I think maybe Benz or Rolls would buy it. I am fairly whelmed by the stuff they put on regular cars. Luxury cars going for well into the six figure range should have more going for them.

>"Several patents cover PV on motor vehicles powering a small >freezer for instant cold ac. Shorter trips are very common so it >would save a considerable amount of fuel. "

In the old days I was told that a car AC takes about 12 HP. I do not know how accurate that is but we are talking back in the days when we had V8 engines, which before the were detuned didn't even need a kick up for the idle to stop them from stalling. I had many cars with over 300 HP and a few with over 400. That puny compressor didn't mean shit to a power plant like that..

But those AC systems were different. They had an accumulator, because everyone knew almost all of them leaked. I had ONE CAR that did not leak Freon and considered it a fluke. They also had thermostatically controlled expansion valves. The newer cars, sometime in the 1980s they got cheap and it became a critical charge cap tube system.

Anyway, PV system running a freezer or whatever, so it runs all the time ? I imagine it would be thermostatically controlled and when you are not pumping hot air through there it probably shuts down just to save wear and tear..

Are they actually on any vehicles on the road or is this just more of those patents sitting on the shelf kike for the water injection carberator ? I would think some of these Emirs and Sheiks in the middle east who are made of money might have something like that.

Another thing about PVs, it is probably not recommended for places like Ohio because we have to sweep feet of snow off the cars in the winter. Are they adversely affected by the cold itself though ?

The other thing about the PVs running the AC all the time is that some people actually put their car in the garage. I am pretty sure that in the US most people don't, and use the garage for storage and whatever. Hell I have parties in mine.

In fact I would like to have a way to cool the garage without using a to of electricity. It already costs a fortune just to cool the house. When giving direction to people who have never been here I tell them to look for the house they think has the highest heating and cooling bills on the street. I got the wintertime beat with the wonder of propanium. Only went through three tanks last winter. But cooling is a big problem. And I am pretty sure it is too humid here to use a swamp cooler. Plus, even though I rewired the garage all in conduit and it could handle many amps, the feed from the house can't, plus I don't want to use them.

If I could get enough PVs on the roof of the garage and use something like that patented gizmo for cars it would probably work. Hell with PVs I could just put a thermostat in there and let it run all the time. But how bad it the wear and tear factor here ?

Just some ideas...

 

"You can freeze during the day - there is a less popular heat pump
refrigeration type that uses ammonia and no moving parts - it simply >has a
thermostatically controlled heating element at a specific point in >the
plumbing. "

I have read about those and actually always wanted one. They are called absorption and there is water in the system, so the material used must withstand that because you REALLY do not want a leak. Also there is a limit as to how far the condenser and evaporator can be, and they must be positioned to take advantage of gravity. I don't believe they had to be perfectly level, but that property made them unsuitable for some applications.

Don't take all that to the bank, I read that stuff at least 20 years ago.

 

[Ian Field]

"Tim Wescott" <tim@seemywebsite.com> wrote in message
news:eYSdnQW7IMVYo_bKnZ2dnUU7-bmdnZ2d@giganews.com...

On Wed, 22 Jun 2016 16:47:45 -0700, Jim Thompson wrote:

On Wed, 22 Jun 2016 18:41:59 -0500, Tim Wescott
seemywebsite@myfooter.really> wrote:

On Wed, 22 Jun 2016 16:14:18 -0700, Bret Cahill wrote:

90% of the electric bill in the desert at this time of the year is
HVAC.
The rest of the house doesn't need so much power and only requires a
small low cost battery for night time.

Freeze about 2 tons of water during the day and then sink heat into
the ice at night. Maybe 2/3rds of the solar power goes to running
the conventional AC or heat pump during the day and 1/4 goes to
freezing water for evening and night time cooling.

Load level with the freezer unit and the much smaller battery. When
the power from the PV is temporarily reduced by clouds the freezer
unit would cut off while the heat pump would remain running. The
clouds should cool things off anyway.

In winter the heat pump would melt a tank of paraffin for night time
heating.


Bret Cahill

Sounds good. You got room for that much water? IIRC, there's energy
losses involved in pushing a given amount of heat farther than it
'needs' to be -- so it may be more efficient to find a substance that
freezes at 60 degrees F or so, is cheap, easy to handle, has a
significant heat of fusion, and isn't something that would turn the
entire neighborhood into a superfund site if the tank leaks. Maybe some
other wax, from the same place you're getting your 80-degree (or 100
degree, or whatever) paraffin.

Note that I managed to dodge taking thermodynamics in school -- so go do
your own math on this.

If it was a good idea someone would be already doing it. Daytime power
is at ON-Peak rates. You'd be better off to use night-time OFF-peak
rates to freeze some ice for you to sit on during the daytime ;-)

Since I'm now chief cook and bottle-washer while my wife recuperates
from 5 hours of back surgery, I do all clothes and dish-washing in the
early morning... (summer) ON-Peak here is 1PM to 9PM.

...Jim Thompson

I think Bret was thinking of off-grid stuff.

But yes, freeze over night, melt during the day if that's what's
favorable.

You can freeze during the day - there is a less popular heat pump
refrigeration type that uses ammonia and no moving parts - it simply has a
thermostatically controlled heating element at a specific point in the
plumbing.

A small array of curved reflectors/collectors would suffice to focus a beam
of sunlight on the bit that needs to get hot.

 

[Bret Cahill]

"Several patents cover PV on motor vehicles powering a small freezer >for instant cold ac."

I got into a van once that seemed to have instant cold air. It had sat for a while. The only thing I can think of is they shut off a valve and maintain the pressures in the refrigeration system. Automotive compressors have no problem starting under load. The house units have little starting torque so that would be impossible unless maybe you use a DC motor.

If you are a thermodynamics guy I have a question. It is one of those "Will this contraption work ?". I am pretty sure it would be impractical with today's technology, but is the principle sound ?

Air conditioning that simply uses air. You know how a diesel engine works.. It is not friction that heats the air it is the fact that you are squeezing the same BTUs of heat into a much smaller space.

So, take a high pressure air compressor and pump up a heat exchanger (like a condenser but does not condense), stick in front of the car or whatever to cool and then just let the air out at whatever CFM you want for the cooling.

I understand the difficulty in getting a compressor that can deliver that much air at that pressure, but if you could would it work ? Or are there inefficiencies of which I am unaware that make it totally unworkable ?

Don't mean to hijack but the topic has to do with air conditioning so...

Gas is actually a better working fluid than liquid/vapor from a pure thermodynamic cycle POV, refrigeration or heat engines.

The reason vapor wins out in refrigeration is the same as for external combustion, steam power v Stirling: The heat transfer coefficient is much higher with a liquid than a gas.

Looking at a thermocycle only makes sense if you have infinite surface areas, an infinite amount of time to waste, etc.

"There should always be a cold non alcoholic drink at the ready >near the front seat."

Isn't there a luxury car out there somewhere with a cooled drink holder ? I know it is possible but I would not attempt to use a Peltier in it. You would have to water cool that or it would melt the pimp rest.

If such a thing were developed I had another harebrained idea for it. A gimbal type mechanism that makes a cover unnecessary. I used to take lunch with this guy we called Smitty who drove like a maniac. Like in my younger day at the tire shop the wear charts that told you if you had bad ball joints or whatever, mine were always "excessive speed on turns". Sometimes we ate in his car and even with the cover sometimes a drink would spill some. So I developed a technique of kinda holding it at the top and let the cup tilt to let it cancel out the Gforces produced. So I was thinking of some sort of mechanism that would do that.

Couple a device like that with a cooling system of some sort and I think maybe Benz or Rolls would buy it. I am fairly whelmed by the stuff they put on regular cars. Luxury cars going for well into the six figure range should have more going for them.

An acquaintance claims his BMW condenses drinking water from AC.

BMW likes to attempt new stuff like that.

"Several patents cover PV on motor vehicles powering a small >freezer for instant cold ac. Shorter trips are very common so it >would save a considerable amount of fuel. "

In the old days I was told that a car AC takes about 12 HP. I do not know how accurate that is but we are talking back in the days when we had V8 engines, which before the were detuned didn't even need a kick up for the idle to stop them from stalling. I had many cars with over 300 HP and a few with over 400. That puny compressor didn't mean shit to a power plant like that.

The ice wouldn't last forever. It would be mostly for 1 or 2 short trips/day.

But those AC systems were different. They had an accumulator, because everyone knew almost all of them leaked. I had ONE CAR that did not leak Freon and considered it a fluke. They also had thermostatically controlled expansion valves. The newer cars, sometime in the 1980s they got cheap and it became a critical charge cap tube system.

Anyway, PV system running a freezer or whatever, so it runs all the time ? I imagine it would be thermostatically controlled and when you are not pumping hot air through there it probably shuts down just to save wear and tear.

Maybe size the ice part large enough so it runs whenever the sun is up.

Are they actually on any vehicles on the road or is this just more of those patents sitting on the shelf kike for the water injection carberator ? I would think some of these Emirs and Sheiks in the middle east who are made of money might have something like that.

Another thing about PVs, it is probably not recommended for places like Ohio because we have to sweep feet of snow off the cars in the winter. Are they adversely affected by the cold itself though ?

PV loses up to 20% efficiency in the desert heat.

The other thing about the PVs running the AC all the time is that some people actually put their car in the garage. I am pretty sure that in the US most people don't, and use the garage for storage and whatever. Hell I have parties in mine.

In fact I would like to have a way to cool the garage without using a to of electricity. It already costs a fortune just to cool the house.

When giving direction to people who have never been here I tell them to look for the house they think has the highest heating and cooling bills on the street. I got the wintertime beat with the wonder of propanium. Only went through three tanks last winter. But cooling is a big problem. And I am pretty sure it is too humid here to use a swamp cooler. Plus, even though I rewired the garage all in conduit and it could handle many amps, the feed from the house can't, plus I don't want to use them.

If I could get enough PVs on the roof of the garage and use something like that patented gizmo for cars it would probably work. Hell with PVs I could just put a thermostat in there and let it run all the time. But how bad it the wear and tear factor here ?

That's why the no moving parts refrigeration + solar thermal could be cheaper than a conventional compressor + PV. The only moving part other than a blower would be for solar tracking.

Maybe they'll come out with an efficient thermo electric freezer that would eliminate all moving parts except the blower.


Bret Cahill

 

>"Maybe they'll come out with an efficient thermo electric freezer >that would eliminate all moving parts except the blower."

Maybe. But right now IIRC a Peltier cooler for the microprocess in a computer pulls about 70 watts, which is more than most of them pull unless under extremely heavy load.

But they do have them in some portable refrigerators or coolers. I do not know what they pull but it must be quite a bit.

However running a compressor is not cheap either. Between friction and the inertia of the piston(s) that is a load. In fact that is the limiting factor in a car engine except for valve float and that has been practically eliminates by new valve train designs with roller lifters and all that. We did a head job on an Ecotech and the valve train almost has no mass. /there is also something known as the desmodramic valve train which does not use springs, at least not mainly. The cam is slotted and actually pulls the valves closed. However none of this gets rid of the problem of piston mass, which is the ultimate end of the horsepower curve.

There are also newer compressor designs like scroll compressors. Even though at 1,750 RPMs the piston mass is not that much of a factor, it is still there. Scroll compressors are only used in very large installations. That is when it makes a difference that is measurable.

One thing I wonder, why can't they just use a friggin DC motor in a sealed compressor in a car ? These wiggers etc. have car stereos that pull 60 or 70 amps. That should be enough. Also, could use PVs to run it when the car is off and/or charge the battery. I mean the ones going down the road sounding like they are about to blow the trunk lid off.

I bet it would be alot less of a hassle in a hybrid, which I imagine has a hell of alot beefier electrical system. And once we get to the point where totally electric cars are economically viable it seems that is the way to go.

And electric cars are. Even though we can't do it now, it is the future. You eliminate the transmission because the low end torque starts at zero RPM. One concept car had a motor for each wheel which eliminated any differential gearboxes further reducing weight. It might be a good idea to still have driveshafts to reduce unsprung weight, it depends on how small they can make the motors.

Plus when it comes to AC, if there is no idle there would be no AC the way it is now.

They got pretty good insulating materials now, even without PV an electric car should handle instant AC. But it is going to take ten years to get electric cars into the mainstream. People simply canot afford them, the cheapest Tesla is seventy grand.

You know, they had electric cars back in the early 1900s. I'll have to find the book on it, which was printed back then so it is definitely not bullshit, of just the accelerator pedal switch. It had countless connectors on it as it rearranged the windings of the motor to achieve speed control. Of course now we got FETs, in fact banks of FETs like those RC cars they race around with. And though it is hard to implement, brake recharging.

So with a system like that, electric AC is obviously the only way to go. However, we need a shitload of nuclear power plants do supply the electricity to charge them.

Even hear of thorium reactors ? There is enough thorium around to last a long time. It has different properties and there is something about its operating temperature, makes it very attractive. However countries are not developing it because they do not want to lose the ability to make weapons grade fissibles. I shit you not, look it up on wiki. I forgot what the difference is but it has to do with the cooling process. As a thermodynamics gguy you know that heat will not really produce power, it is the differential of heat. Take a Stirling engine and have both sides the same temperature and see what doesn't happen. It is the differential that makes things happen.

Some scientists say thorium would be more efficient than what we got got. Some also say it would be safer. But nobody is working on it because they want the weapons grade breeded or centrifuged or whatever plutonium. And at least the US wants the depleted uranium for use in ballistic weapons because it can pierce armor.

Nuclear is the only place I see that is dominated by the want for weapons. All other alternatives are simply not viable right now. The technology is not there yet. Oil companies are not addicted to oil, they are addicted to money. If anything was price comparable they would be selling it yesterday. In fact being publicly traded they are compelled to do so. If anyone ever found out they were hiding a viable alternative energy and not developing and selling it because they love kissing that Saud's hand they could be accused of conflict of interest, accused of taking bribes, investigated, all their bank records examined. That is how business is when you are on the stock market. So they would have no choice.

So right now, the electric car is out. First of all the batteries are an environmental nightmare. Fuel cells are also a mess, we experimented with cracking water and it is dangerous. And PV is simply not powerful enough to drive a car the way people want to drive. And though I do not know it because I am not a thermodynamics guy, for some reason nobody is getting into thorium.

If all that was economically viable they would be selling it now.

 

[Jasen Betts]

On 2016-06-29, jurb6006@gmail.com <jurb6006@gmail.com> wrote:

"You can freeze during the day - there is a less popular heat pump
refrigeration type that uses ammonia and no moving parts - it simply >has a
thermostatically controlled heating element at a specific point in >the
plumbing. "

I have read about those and actually always wanted one. They are called absorption and there is water in the system, so the material used must withstand that because you REALLY do not want a leak. Also there is a limit as to how far the condenser and evaporator can be, and they must be positioned to take advantage of gravity. I don't believe they had to be perfectly level, but that property made them unsuitable for some applications.

Don't take all that to the bank, I read that stuff at least 20 years ago.

As I recall "adsorbtion" and the pipes contain, ammonia, water, and
hydrogen.

--
This email has not been checked by half-arsed antivirus software

 

[Bob Masta]

On Tue, 28 Jun 2016 17:04:05 -0700 (PDT), jurb6006@gmail.com
wrote:

"Several patents cover PV on motor vehicles powering a small freezer >for =
instant cold ac."

I got into a van once that seemed to have instant cold air. It had sat for=
a while. The only thing I can think of is they shut off a valve and mainta=
in the pressures in the refrigeration system. Automotive compressors have n=
o problem starting under load. The house units have little starting torque =
so that would be impossible unless maybe you use a DC motor.=20

If you are a thermodynamics guy I have a question. It is one of those "Will=
this contraption work ?". I am pretty sure it would be impractical with to=
day's technology, but is the principle sound ?

Air conditioning that simply uses air. You know how a diesel engine works. =
It is not friction that heats the air it is the fact that you are squeezing=
the same BTUs of heat into a much smaller space.=20

So, take a high pressure air compressor and pump up a heat exchanger (like =
a condenser but does not condense), stick in front of the car or whatever t=
o cool and then just let the air out at whatever CFM you want for the cooli=
ng.=20

I understand the difficulty in getting a compressor that can deliver that m=
uch air at that pressure, but if you could would it work ? Or are there ine=
fficiencies of which I am unaware that make it totally unworkable ?=20

I recall a Popular Science article from the mid-late '60s
that featured a "direct air" car air conditioner, which
supposedly got cold super fast and actually created frost on
the air outlet.

Alas, as with most of the PS articles of the era, that was
the last anyone heard of that "amazing new invention"...
<g>

Best regards,


Bob Masta

DAQARTA v9.20
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Scope, Spectrum, Spectrogram, Sound Level Meter
Frequency Counter, Pitch Track, Pitch-to-MIDI
FREE 8-channel Signal Generator, DaqMusiq generator
Science with your sound card!

 

[Bret Cahill]

"You can freeze during the day - there is a less popular heat pump
refrigeration type that uses ammonia and no moving parts - it simply >has a
thermostatically controlled heating element at a specific point in >the
plumbing. "

I have read about those and actually always wanted one. They are called absorption and there is water in the system, so the material used must withstand that because you REALLY do not want a leak. Also there is a limit as to how far the condenser and evaporator can be, and they must be positioned to take advantage of gravity. I don't believe they had to be perfectly level, but that property made them unsuitable for some applications.

Don't take all that to the bank, I read that stuff at least 20 years ago.

As I recall "adsorbtion" and the pipes contain, ammonia, water, and
hydrogen.

OSHA thinks it's OK for the local produce coolers to use huge ammonia systems with a lot of fork lifts operating nearby. It's easy to tell a cooler from a warehouse in the desert by all the thick power lines coming from the substation on the adjacent lot.

Properly contained with a thermo fluid oil delivering the heat from the collectors to the sealed refrigeration loop it could be made safe enough for household use, as safe as a Li-Ion PowerWall.

How costs would compare with PV powered refrigeration on any volume basis is a big messy job but the parts for a PV prototype for motor vehicles are actually cheaper than to have a new conventional AC installed.

It would be best if first tried on a small cab PU with a topper. Glue PV cells on the topper so the resale value of the truck doesn't drop too much, put the freezer and inverter in the bed.


Bret Cahill

 

On Wednesday, June 22, 2016 7:58PM, Jim Thompson
<To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:

On Wed, 22 Jun 2016 20:43:33 -0500, Tim Wescott <t...@seemywebsite.com
wrote:

On Wed, 22 Jun 2016 16:47:45 -0700, Jim Thompson wrote:

On Wed, 22 Jun 2016 18:41:59 -0500, Tim Wescott
seemywebsite@myfooter.really> wrote:

On Wed, 22 Jun 2016 16:14:18 -0700, Bret Cahill wrote:

90% of the electric bill in the desert at this time of the year is
HVAC.
The rest of the house doesn't need so much power and only requires a
small low cost battery for night time.

Freeze about 2 tons of water during the day and then sink heat into
the ice at night. Maybe 2/3rds of the solar power goes to running
the conventional AC or heat pump during the day and 1/4 goes to
freezing water for evening and night time cooling.

Load level with the freezer unit and the much smaller battery. When
the power from the PV is temporarily reduced by clouds the freezer
unit would cut off while the heat pump would remain running. The
clouds should cool things off anyway.

In winter the heat pump would melt a tank of paraffin for night time
heating.


Bret Cahill

Sounds good. You got room for that much water? IIRC, there's energy
losses involved in pushing a given amount of heat farther than it
'needs' to be -- so it may be more efficient to find a substance that
freezes at 60 degrees F or so, is cheap, easy to handle, has a
significant heat of fusion, and isn't something that would turn the
entire neighborhood into a superfund site if the tank leaks. Maybe some
other wax, from the same place you're getting your 80-degree (or 100
degree, or whatever) paraffin.

Note that I managed to dodge taking thermodynamics in school -- so go do
your own math on this.

If it was a good idea someone would be already doing it. Daytime power
is at ON-Peak rates. You'd be better off to use night-time OFF-peak
rates to freeze some ice for you to sit on during the daytime ;-)

Since I'm now chief cook and bottle-washer while my wife recuperates
from 5 hours of back surgery, I do all clothes and dish-washing in the
early morning... (summer) ON-Peak here is 1PM to 9PM.

...Jim Thompson

I think Bret was thinking of off-grid stuff.

But yes, freeze over night, melt during the day if that's what's
favorable.

Do they buy energy back during on-peak at on-peak pricing?

I don't do solar... solar is for fairies >:-}

Just google 'shopping' and 'solar air conditioner'.

 

seb
jurb...@gmail.com wrote:

I got into a van once that seemed to have instant cold air. It had sat for a while. The only thing I can think of is they shut off a valve and maintain the pressures in the refrigeration system. Automotive compressors have no problem starting under load. The house units have little starting torque so that would be impossible unless maybe you use a DC motor.

If you are a thermodynamics guy I have a question. It is one of those "Will this contraption work ?". I am pretty sure it would be impractical with today's technology, but is the principle sound ?

Air conditioning that simply uses air. You know how a diesel engine works.. It is not friction that heats the air it is the fact that you are squeezing the same BTUs of heat into a much smaller space.

I heard a couple of truck-drivers talking about how marijuana-seed oil has a similar octane effect.