ScottCrane
New Member
- Joined
- Sep 28, 2020
- Messages
- 3
Been reading about cooling panels. Best/cheapest DIY approach appears to be the water spray idea. To me, using collected rainwater would make it feel less wasteful of H20. Other new idea is to use a phase change material on the bottom to absorb and release heat. Lastly, is making some kind of water jacket; like those CPU/GPU coolers. Sounds expensive to me.
But, the water jacket had me thinking about perhaps using Pex Al Pex with aluminium fins to cool the bottoms. Pex Al Pex is a special Pex/Aluminium/Pex construction made for radiant heating and cooling. The "fins" are approx 4" wide and 2' or 4' sections of aluminium flashing type material. The fins are put thru a former to bend a half radius in the middle to fit the Pex-Al-Pex into. The idea is warm (or cold) water is passed thru the Pex and transferred to the fins. Thus warming your tootsies on a cold winter's night Google pex al pex fins and you will see what they look like.
So, as you may have guessed, the idea is to run the Pex-Al-Pex up and down the backside of the panels with fins attached to help with the transfer to heat from the panel to the fins to the cooling water. What would even be a bonus with this idea is if the panels could heat the water up enough to make it worth capturing and saving in a thermal storage for hot water usage.
I'm guessing in your head you are wondering: Dude sounds cool, how much is this gonna cost ya? Well, 1/2" Pex-Al-Pex runs about $0.42/ft (link). The 1/2" PEX Aluminum Heat Transfer Plates, I call them fins, (link) run just under $0.25/ea for a 4' chunk. So, back of the napkin says I want to run four lengths of Pex-Al-Pex up and down my 6' panels. And have four of the 4' fins. So, roughly $10 for the Pex-Al-Pex and another $1 for the fins. Probably add a few more $ for in/out connectors. Then some inexpensive "master controller" Arduino setup, or maybe a Wifi enabled Pi. Of course a warm water pump and cooling, etc.
Without some serious number crunching on the sizing, I picked 4 long runs of the Pex-Al-Pex per panel. To reduce the cost per panel, I might try just a pair of runs on one panel and four on another. Then capture/save/plot the difference between the uncooled panel and its neighbor one with two and four runs. Then compare all three panels apples to apples conditions. If would also be nice if I could find a way to figure out what each panel is putting out by themselves even when wired in series/paralleled in an array. I suppose measuring voltage wouldn't be an issue and current could be done with an external inductance measuring coil type sensor. The assumption is the cooled panels ought to be pushing out more and this should be proportional to the amount of cooling.
This way I get real world data and not just some theoretical guess. And it would help in determining if spending the extra $ for this type of cooling is feasible and what the payback would be. Since I also already have some of the water spray equipment (my drip garden left overs), it wouldn't be difficult to try it on one of the other panels was well. Part of me likes the closed loop Pex-Al-Pex system, but the spray beats it price wise. Let's see what the real world results are going to be.
But, the water jacket had me thinking about perhaps using Pex Al Pex with aluminium fins to cool the bottoms. Pex Al Pex is a special Pex/Aluminium/Pex construction made for radiant heating and cooling. The "fins" are approx 4" wide and 2' or 4' sections of aluminium flashing type material. The fins are put thru a former to bend a half radius in the middle to fit the Pex-Al-Pex into. The idea is warm (or cold) water is passed thru the Pex and transferred to the fins. Thus warming your tootsies on a cold winter's night Google pex al pex fins and you will see what they look like.
So, as you may have guessed, the idea is to run the Pex-Al-Pex up and down the backside of the panels with fins attached to help with the transfer to heat from the panel to the fins to the cooling water. What would even be a bonus with this idea is if the panels could heat the water up enough to make it worth capturing and saving in a thermal storage for hot water usage.
I'm guessing in your head you are wondering: Dude sounds cool, how much is this gonna cost ya? Well, 1/2" Pex-Al-Pex runs about $0.42/ft (link). The 1/2" PEX Aluminum Heat Transfer Plates, I call them fins, (link) run just under $0.25/ea for a 4' chunk. So, back of the napkin says I want to run four lengths of Pex-Al-Pex up and down my 6' panels. And have four of the 4' fins. So, roughly $10 for the Pex-Al-Pex and another $1 for the fins. Probably add a few more $ for in/out connectors. Then some inexpensive "master controller" Arduino setup, or maybe a Wifi enabled Pi. Of course a warm water pump and cooling, etc.
Without some serious number crunching on the sizing, I picked 4 long runs of the Pex-Al-Pex per panel. To reduce the cost per panel, I might try just a pair of runs on one panel and four on another. Then capture/save/plot the difference between the uncooled panel and its neighbor one with two and four runs. Then compare all three panels apples to apples conditions. If would also be nice if I could find a way to figure out what each panel is putting out by themselves even when wired in series/paralleled in an array. I suppose measuring voltage wouldn't be an issue and current could be done with an external inductance measuring coil type sensor. The assumption is the cooled panels ought to be pushing out more and this should be proportional to the amount of cooling.
This way I get real world data and not just some theoretical guess. And it would help in determining if spending the extra $ for this type of cooling is feasible and what the payback would be. Since I also already have some of the water spray equipment (my drip garden left overs), it wouldn't be difficult to try it on one of the other panels was well. Part of me likes the closed loop Pex-Al-Pex system, but the spray beats it price wise. Let's see what the real world results are going to be.