50 years ago a CoP of 4 was magic. Now mini-split achieving those regularly.
Right?? CoP of 4 feels like an incredible feat to have normalized.
Have you seen Solar Thermal Hybrid A/C units?
Systems that use additional heat from the sun to increase dissipation and extract work? Never in person, only read about the concept of heat flow being proportional to delta T and solar thermal collector allows increasing of delta T and therefore increase heat flow..? Maybe I am still misunderstanding some aspects.. It’s a concept I want to learn more about, because it’s so interesting efficiency wise.
Some commercial places use water as a thermal buffer, freeze ice at night and thaw at day to quench heat load. That’s super neat because H2O is abundant and it sidesteps need for batteries.
Solar Thermal Hybrid AC sounds really interesting in a similar spirit of using a relatively accessible and affordable technology to improve the overall efficacy of the system.
Thanks for sharing!!
The Solar Air Conditioning unit works on a hybrid principle. It absorbs solar energy to heat the inside medium by utilizing a vacuum solar collector. The refrigerant from the compressor goes through a copper coil inside the collector and undertakes a heat exchange. The heated refrigerant then goes through a cycle inside the system for not only for heating but also for cooling too. Energy from the sun is fully utilized so therefore less power is required from the mains in this process, this, in turn, allows for smaller compressors to be installed that offer even better savings on power consumption. This system adopts a four-fold type heat exchanger as one of the core components of this air-conditioner. Its heat effective area is increased by 20-30% versus the usual V-type and flat plate heat exchanger, which greatly increases cooling efficiency.
found this helpful document about hybrid AC btw. warning: pdf link
https://pdf.indiamart.com/impdf/8960243397/MY-1848302/hybrid-solar-air-conditioner.pdf
It is like your car going down a gentle slope. You can take your foot off of the accelerator for a longer period as gravity helps your car keep moving. Therefore it is using less energy for a longer period and will lower your power bills even further. But how do Solar Thermal Air conditioners do this? They absorb solar energy by using a thermal collector with copper heat conducting inner coils. The preheated refrigerant from the collector feeds directly into the compressor to reduce the amount of work needed and saves power.
excerpt:
![Screenshot 2021-07-11 at 04-54-48 Hybrid Solar Air Conditioner - PDF Catalogue.png Screenshot 2021-07-11 at 04-54-48 Hybrid Solar Air Conditioner - PDF Catalogue.png](https://diysolarforum.com/data/attachments/55/55788-0451a84c1864e61f21d87958603803ea.jpg)
most of the ones in that brochure seem to be CoP 3.6-3.9. I wonder how the solar collector works into the ratings and stuff.
Like, without the extra heat from outside, it will run at CoP 3.5-4 e.g. at nighttime.
Then during day it maybe run at CoP 4+++ :D
This might sounds weird but it reminds me of
Marx generator. Due to using a weak potential (compressor) combined with a some natural phenomenon (heat flow proportional to delta temperature) to achieve a strong potential (more cooling than compressor alone).
Cheers!
edit: Originally overlooked this part you mentioned about the heat causing the refrigerant flow itself, that sounds super fun! Two fans and a thermal collector and an expansion valve or something..? With a compressor for kickstart or auxiliary use at night.? Cool! Copper heat pipes with low pressure atmosphere and a bit of water and a wick seem to do something similar. Really interesting concept module to try and integrate.
There was also a video on youtube of a liquid pump that was actuated by the phase change from liquid to gas convection but can’t find right now. The fluid seemed to be some high volatility liquid like alcohol or something. they said they don’t know what it’s charged with, but guess that it’s a low boiling point material. edit: found it. warning: linus tech tips. very commercial channel.
video link to time where they start talking
Suppose for now I will have to abandon all hope of using
magnetohydrodynamic drive based compressor ?