Passive energy storage
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curiouscarbon
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great video!
technology connections is always pumped to talk about heat transfer!
technology connections is always pumped to talk about heat transfer!
One of my favorite channels.
curiouscarbon
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From another great channel
Same channel.
curiouscarbon
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It’s their secondary channel!
Yup, his deep thought channel. Love it.
55 gallon plastic drums filled with water. $10 each around here. IBC totes, cage won't fit through the doors. Build interior walls in house thick/deep enough to load with 2 liter pop bottles filled with water. Phase change sheetrock is probably too expensive
Somebody needs to take a wall mount mini split, rotate it 90 degrees, remove the fan blade, immerse it in water. Use it to heat or cool water, a chiller. Zero idea as to if this is possible.
Somebody needs to take a wall mount mini split, rotate it 90 degrees, remove the fan blade, immerse it in water. Use it to heat or cool water, a chiller. Zero idea as to if this is possible.
Short_Shot
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It's possible but you need to circulate the water through the evaporator or you'll have a bad time.
You're far better off just plumbing in an evaporator designed to pump water through it if you're going to rip the whole thing apart anyways.
You can then use that thing to chill a whole bank of drums down over the course of the day....
Or just buy an actual water chiller expressly designed for this purpose. Getting a 1 ton chiller running on solar can't be too difficult and they're already designed to work with your system of pipes and/or reservoir.
I was fortunate enough to spec out a 40 ton unit (2x circuits for redundancy with 2x 10 ton compressors each circuit) about two years ago and it's been running like a top since.
We keep 550 gallons of water at 50F +/- 1F year round for production. But I digress.
But you can do the same thing with geothermal (in certain regions) just by pumping water down into the cool ground and back again in a closed loop without any phase change compressor system involved.
However, there are some rather important concerns which must be properly engineered when using geothermal to prevent fun things such as melting permafrost (if you're in such an area) and sinking your house. And this solution may not work well in every climate.
Natural convection should disperse heat such that a pump isn’t needed.
No pumping needed for our 800 gallon Solartechnics thermal storage tank for DHW needs which is paired with our indoor wood boiler, tank temps range from 150-180f over the course of a fire in the boiler.
I’ve thought about pairing some thermal solar collectors, but the cost wasn’t there and just opted for a hybrid hot water heater, which works great as a basement dehumidifier.
No pumping needed for our 800 gallon Solartechnics thermal storage tank for DHW needs which is paired with our indoor wood boiler, tank temps range from 150-180f over the course of a fire in the boiler.
American Solartechnics, LLC.
Last Updated: March 6th, 2024 December 2nd, 2022 - Between the fire we had this summer and our other business endeavors keeping us busy, we have been considering stepping back from the Heat Bank...
www.americansolartechnics.com
I’ve thought about pairing some thermal solar collectors, but the cost wasn’t there and just opted for a hybrid hot water heater, which works great as a basement dehumidifier.
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Short_Shot
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That's not the case with an evaporator coil. You're likely to freeze the water around it without flow. Even if you don't freeze it you'll likely under load the system such that the compressor is forced to slow down (or just shut off if it's single speed) to let the evap side catch up, assuming the system has appropriate sensors in place.
We've had many evaporators freeze up or otherwise cool down too much and cause the system to shut down as a result of insufficient water or air flow in our building.
The older ones that lacked any way to tell what's going on would just turn into an ice block, and mind you this is using an air conditioner that's not designed to go below freezing normally.
This is very, very different from heating.
Or the delta t of the water of isn’t large enough. Larger mass, greater Delta less freezing.
Same thing for heating, undersized the thermal storage tank or the coil and you’re return temps will spike and you won’t absorb the heat.
Same thing for heating, undersized the thermal storage tank or the coil and you’re return temps will spike and you won’t absorb the heat.
Short_Shot
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Sure. On the surface this is of course true.
If the system is capable of getting the evap circuit below freezing though, it absolutely will start to do so and this will cause a feedback loop of continously decreasing available surface area to do the convection with.
I still have an AC system at work that does this every humid day because it's ancient blower has never had enough cfm to keep the evaporator temp above freezing. The other two in that room are less than 2 years old and work great.
If it can't get the evap that cold no matter what then it'll run forever and you'd definitely be right.
curiouscarbon
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Neato!! H2O’s specific heat capacity per cost is so great! ?
This chiller device states 0.25 ton (3000BTU/hr) using 460W input power. Estimated CoP of 1.9. Suggested 40-90 gallons of water volume to cool. Suggested water flow rate 400-900 gallon / hour circulation.
I got one and plan on experimenting with using it as a daytime fixed load to cool down some insulated buckets of water.
Arduino monitoring temperature of multiple locations (evaporator box, ambient air, water evap inflow, water evap outflow, condenser, etc..) and N-channel MOSFET to switch pump(s) on and off.
At 460 W input from AC power I’ll have to eat the inverter losses and CoP of 1.9 is just okay. Thanks for sharing your experience!
I looked at chillers. Commonly used in bars for beer taps. None seemed to be very efficient especially for the price and none used inverter technology. Somebody needs to make a inverter technology reverse cycle chiller.
Arctic Heat pumps - Cold Climate Air to Water Heat Pumps for Homes and Pools
Arctic series cold climate heat pumps are both advanced and cost effective air source heat pumps with the ability to heat your home, office, pool and more.
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Arctic Heat pumps - Cold Climate Air to Water Heat Pumps for Homes and Pools
Arctic series cold climate heat pumps are both advanced and cost effective air source heat pumps with the ability to heat your home, office, pool and more.
www.arcticheatpumps.com
Split System Heat Pump Water Heaters
Split system heat pump water heaters are super-efficient options that are rare in North America. Here, we look into how they work and which are best.
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Short_Shot
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Yeah. I can believe that.
If you really want one though I don't see why you can't just convert one to a water heat exchanger, assuming you are or know an hvac pro.
Short_Shot
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Just remember to keep that heat outside lol
curiouscarbon
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the cool new thing on the block is fluid sinking air heat sinks so i was thinking of turning the compressor upside down to get thermal dissipation with the water ?jk
got any recommendations for titanium evap chillers that run off dc?
Keep in mind, the mini splits use variable speed compressors and condenser fans, so to get the mini operating on a water coil would require a variable speed water pump, compatible with the condenser controller, and the precise heat transfer of the air coil, adapted to water heat transfer characteristics… we HVAC pros don’t have that kind of skills… that would need a manufacturing engineer…
curiouscarbon
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this thread has me thinking..
why not cool down a large insulated mass of paraffin or water at night by running coolant through a radiator outside and blowing cool outdoors air across the radiator all night. that would be low power draw at night to diffuse the heat into atmosphere.
then during day either directly run the same coolant to indoor radiator to cool down living space, or use that coolant as a mass to pump heat into..
why not cool down a large insulated mass of paraffin or water at night by running coolant through a radiator outside and blowing cool outdoors air across the radiator all night. that would be low power draw at night to diffuse the heat into atmosphere.
then during day either directly run the same coolant to indoor radiator to cool down living space, or use that coolant as a mass to pump heat into..
