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Peter_1
09-11-2015, 08:49 PM
Can someone explain this new technology to me?
I can't figure out the benefits of it.
For some reason, I can't stop thinking this is again something which never can work.
http://solarcoolenergy.com/the-science/

Rob White
09-11-2015, 09:49 PM
.

Right, I understand the principle and I am quite sceptical.
Adding extra heat to the discharge vapour is adding extra superheat, this superheated
vapour will require cooling before the vapour meets it's condensing temp?

This will require a larger surface area to the condenser or more air flow over the condenser
and then the refrigerant will condense. The added superheat would not increase pressure
much but if it did that would just add extra subcooling? So the system would balence out?

Increased installation costs, increased running costs with no real savings that I see,
increased mass flow rate maybe?

So I ask would increased mass flow reduce running costs sufficiently to outweigh increased
installation costs?

I don't know, but I do know the only real cost saving in running a fridge is if you reduce discharge
temps and increase evaporating temps anything else is just snake oil :D

Rob

.

Grizzly
10-11-2015, 06:05 AM
An Interesting link Peter.
Thank you!
I agree with you and Rob.
Snake oil being peddled in more sophisticated ways, is still snake oil.
Grizzly

Peter_1
10-11-2015, 07:03 AM
See you both have the same question marks in your head as I have. How can adding heat, increasing its internal energy at a point (immediately after compressing it to a temperature as low!! as possible to run economical) where you want to reject the extracted heat again as soon as possible be a benefit for a cooling cycle? Where you want that there is as less as possible heat added to the extracted heat? Seems for me they invented the hot water again.

mikeref
10-11-2015, 08:28 AM
Quote: The hotter the sun shines, the more the solar panel takes over the compressing of the gas and the more power is saved. The compressor acts now mainly as a pump, providing the necessary cycle flow....:confused:
--------------------------
Conventional discharge Temperatures would be in the 60 to 80 ish Deg C range.
Just how big would this Solar Panel have to be considering the volume of gas at say 70 C moving through it for commercial Refrigeration and A/C's? ( Any significant solar heat input?)

Rain would turn this setup into an expensive ineffective heat Exchanger.

Just for comparison, my solar hot water can heat 300 Litres of 24 C water to 88 Degrees C within 4 to 5 hours of continuous sunlight, in the middle of the OZ Summer.

Adding any heat to discharge gas only increases the load on the Condenser.:rolleyes:

HVACRsaurus
10-11-2015, 08:51 AM
A subsidiary of endocube corporation?

Combine with an xdx valve and arctic master to receive a free dolphin with each electricity bill

Peter_1
10-11-2015, 08:38 PM
A subsidiary of endocube corporation?

Combine with an xdx valve and arctic master to receive a free dolphin with each electricity bill
Perfect :rolleyes: a free dolphin LOL
Indeed, the Endocube and the XDX valve...I can't believe anyone believes one word of this.

frank
11-11-2015, 10:05 PM
Adding any heat to discharge gas only increases the load on the Condenser.:rolleyes:

I would also think that it would have an effect on current draw as the compressor tries to overcome the increasd pressure the other side of the discharge reed

NH3LVR
12-11-2015, 08:42 PM
"The compressor compresses the gas, it is easier for the compressor to compress a gas in comparison to a liquid which means less power is needed by the compressor."

This part is true, as anyone who has rebuilt a compressor that tried to pump liquid can tell you.
As Peter_1 suggested we need to combine this with the Endocube and the XDX Altered Bi-Phase Flow/High Vapor Fraction Turbulent technology that allows for increased heat transfer coefficients.
Let us not forget the Oil Catalyst as well.

My theory about the success stories are that the person who bought this cannot admit they got fooled.
Instead of a Dolphin can I have a Unicorn instead?

Six months retired and loving it.

Segei
16-11-2015, 12:10 AM
I agree that this is snake oil. Mass flow will not increase because it depends of compressor capacity. Additional heat (I'm doubt that anything can be added) added to discharge gas slightly increase load on condenser.

MikeHolm
25-11-2015, 11:32 PM
I've been trying to find a way to do this for years. What goes in must come out. To have a variable input evap you must use a VSD on the pot and a variable capacity condenser. Not an easy task and i've never figured out how to do it, much as I'd like to combine my panels with an ASHP

mikeref
26-11-2015, 07:49 AM
If i were to quote these two sentences only...
"The hotter the sun shines, the more the solar panel takes over the compressing of the gas and the more power is saved. The compressor acts now mainly as a pump, providing the necessary cycle flow."

Would it be possible this Solar Panel is nothing more than a power source for a high pressure Vapor Pump? If more sunlight were to reduce compressor load, something other than the Condenser would have to reduce head pressure at the point of origin.

Your thoughts fellow Tech's.:)

Segei
27-11-2015, 12:32 AM
I've been trying to find a way to do this for years. What goes in must come out. To have a variable input evap you must use a VSD on the pot and a variable capacity condenser. Not an easy task and i've never figured out how to do it, much as I'd like to combine my panels with an ASHP
I didn't get it. Did you try to heat discharge gas?

Segei
27-11-2015, 12:45 AM
If i were to quote these two sentences only...
"The hotter the sun shines, the more the solar panel takes over the compressing of the gas and the more power is saved. The compressor acts now mainly as a pump, providing the necessary cycle flow."

Would it be possible this Solar Panel is nothing more than a power source for a high pressure Vapor Pump? If more sunlight were to reduce compressor load, something other than the Condenser would have to reduce head pressure at the point of origin.

Your thoughts fellow Tech's.:)
Major misinterpretation in this "technology" is that heat compress the gas. This is wrong. Heat is byproduct of compression. We need compression to condense refrigerant. Heat on discharge side of the cycle will increase load on condenser but compressor load will not change. It is easy to test by installing electrical heater to heat discharge gas.

Magoo
27-11-2015, 04:23 AM
cannot understand how a solar panel that adds heat to discharge gas is efficient. Only positive is if I was selling solar panels, similar to that snake oil Ice COLD crap.
All we are doing is shifting heat from one point to another , adding more heat to do it.

Hi NH3LVR good to read you are enjoying retirement

Josip
27-11-2015, 07:56 AM
Hi all,

had not time to study this matter in detail, fortunately, from one of our valuable member got some links and some info he got from manufacturer ... seems this is only working when unit goes into heating mode .... and still without any reliable answer ... sounds more like marketing without any energy savings ...

anyhow, here are some links ....

https://www.youtube.com/watch?v=uQ92SNSln7Q

http://www.edwardmarcsphilinc.com/sedna-aire-solar-aircon-works-enhance-energy-savings-cooling-comfort/#!prettyPhoto

comments ....

Best regards, Josip :)

mikeref
27-11-2015, 08:42 AM
Major misinterpretation in this "technology" is that heat compress the gas. This is wrong. Heat is byproduct of compression. We need compression to condense refrigerant. Heat on discharge side of the cycle will increase load on condenser but compressor load will not change. It is easy to test by installing electrical heater to heat discharge gas.

We Know thermal energy relocation is our job.The conventional mechanical process is slowly moving forward so we use COP as a reference. Peter 1's link is somewhat BS...OR ..Am i missing out on buying a truck load of Shares. :cool:

hookster
27-11-2015, 08:27 PM
I don't think they are adding extra super heat to the high side but rather scaling back the compressor work and using the solar energy to increase heat of compression back up to design conditions.

It does sound a feasible principle but obviously there must be some sort of cost, complexity, patent costs and design issues that is not making it actually payback quick enough!

MikeHolm
15-01-2016, 12:49 AM
I didn't get it. Did you try to heat discharge gas?

Wow, I really haven't been on here for a while.

I looked at heating discharge gas and I looked at adding heat directly to the evap coils but couldn't make the energy balance work in any controllable way. The problem is the nature of solar and it's unpredictability. Anyway, it is on the back burner for now.

theboss
18-01-2016, 11:55 PM
The only way you can have a real solar assisted condenser is when you wire the fans to run out of Solar power...or hook up an on-grid inverter to live feed part of the load from solar.

LG has a home split unit with solar panel mounted on it but i wonder how much energy you are actually saving by diverting small indoor and outdoor motor to solar while the real energy hog is the compressor?

AC_From_Hell
20-01-2016, 07:12 AM
Id say that at the moment the only feasible solar assisted( or entirely solar ) system is an absotption chiller combined with solar thermal vacuum tube panels. I have seen this kind of installations and it works great. I will make one for me in the near future.

theboss
21-02-2016, 11:23 PM
I've been trying to find a way to do this for years. What goes in must come out. To have a variable input evap you must use a VSD on the pot and a variable capacity condenser. Not an easy task and i've never figured out how to do it, much as I'd like to combine my panels with an ASHP

You can build a condenser with small tube and multiple circuit with a check valve on the exit of each circuit into common header. The inlet is control by electronic valve. Together with an intelligent logic control the condenser inlet valve respond to load conditions and vary or shut off refrigerant flow to each circuit.

theboss
21-02-2016, 11:27 PM
Id say that at the moment the only feasible solar assisted( or entirely solar ) system is an absotption chiller combined with solar thermal vacuum tube panels. I have seen this kind of installations and it works great. I will make one for me in the near future.

I am working on a prototype unit which is powered directly by solar and stores cold as ice for off-sun use.
This allows maximum power tracking of solar and run the compressor at peak output according to available solar energy...the cold is stored as ice and can be used at night to air condition the bedroom for sleeping...

There are DC drives available which can take direct solar DC power in the range of 450-600 VDC and turn it out into AC 3 Phase. Variable speed compressor would be best for this!

theboss
22-02-2016, 09:46 PM
Add heat to discharge by solar is doing exactly this!



Operation of an air conditioner at elevated ambient temperatures inherently results in a lowercoefficient of performance (COP). This conclusion comes directly from examining the Carnotcycle. The COP relation, COP=Tevap/(Tcond-Tevap), indicates that the COP decreases when thecondenser temperature increases at a constant evaporation temperature. This theoreticalindication derived from the reversible cycle is valid for all refrigerants. For refrigerantsoperating in the vapor compression cycle, the COP degradation is greater than that for the Carnotcycle and varies among fluids. The two most influential fundamental thermodynamic propertiesaffecting this degradation are a refrigerant’s critical temperature and molar heat capacity. (e.g.,McLinden 1987, Domanski 1999). For a given application, a fluid with a lower critical temperaturewill tend to have a lower COP

http://fire.nist.gov/bfrlpubs/build02/PDF/b02186.pdf