(SOLVED) Solving the climate control crises

[MAGE]

They're extended video after use says that it only works for one person and if you're standing in front of it. The ice in this cooler from this video lasts for 2 days. I think this is going to work guys, my dad says he has some aluminum pipe I can use to try this out when my ICECO arrives. I'm very sad that I didn't get a chance to get the ICECO 3 in 1 for $299 on Indiegogo when I had the chance and now have to pay basically double the price.

Also in the video they said that their ducting that they used fills up with water as the ice melts so I want to make sure that mine doesn't get water in the duct (or the pipe) that I use.

I've settled on the type of fan that I'm going to use, it's going to be a low wattage AC fan. There simply aren't any good 12v fans that i have found that and quiet enough but this is the one that I'm going to get. Also I haven't found any quiet 12v marine inline fans that allow for continuous use like these do

Amazon.com: AC Infinity CLOUDLINE T4, Quiet 4” Inline Duct Fan with Temperature Humidity Controller - Ventilation Exhaust Fan for Heating Cooling Booster, Grow Tents, Hydroponics : Patio, Lawn & Garden

Amazon.com: AC Infinity CLOUDLINE T4, Quiet 4” Inline Duct Fan with Temperature Humidity Controller - Ventilation Exhaust Fan for Heating Cooling Booster, Grow Tents, Hydroponics : Patio, Lawn & Garden

www.amazon.com

It has variable temperature control, which seems pretty cool. No pun intended.

Can't wait to order this stuff and try it out!

 

[Supervstech]

The water in the pipe isn't from the ice melt, it is from the humid air being chilled...

 

[MAGE]

Oh true I guess I would have to dump that out every now and then. I think it's going to work though I'm shipping all this stuff to my dad's house I hope it works. The ducting that they used in this video isn't sealed though so I bet there must be a bit of water getting in there possibly but I'm not sure.

 

[curiouscarbon]

Volunteering randomly: people sometimes discuss what is the minimum BTU/hr needed to help someone be comfortable.

At rest, a single person emits 90-150 Watts of Thermal Energy. Multiply by 3.412 to get BTU/hr.

300-500 BTU/hr absolute minimum. This assumes all the air coming out of the unit goes directly to the person’s skin before interacting with the warm ambient air. Very generous assumption..

If you think of this 500 BTU/hr figure as a 100% delivery efficiency situation so to speak, 100% goes to cool the skin of the person 500/1.0=500BTU/hr. Now back to reality.

If we assume only 25% of the air will directly cool the person’s skin, then we need 500/0.25=2000BTU/hr.

All this ignores heat coming in from the walls. Strictly talking about mitigating heat coming from human body.

Basically, If I wore some weird suit that directly cooled my body, I would theoretically only need one 500BTU/hr air conditioner to satisfy the cooling requirement.

 

[Supervstech]

Volunteering randomly: people sometimes discuss what is the minimum BTU/hr needed to help someone be comfortable.

At rest, a single person emits 90-150 Watts of Thermal Energy. Multiply by 3.412 to get BTU/hr.

300-500 BTU/hr absolute minimum. This assumes all the air coming out of the unit goes directly to the person’s skin before interacting with the warm ambient air. Very generous assumption..

If you think of this 500 BTU/hr figure as a 100% delivery efficiency situation so to speak, 100% goes to cool the skin of the person 500/1.0=500BTU/hr. Now back to reality.

If we assume only 25% of the air will directly cool the person’s skin, then we need 500/0.25=2000BTU/hr.

All this ignores heat coming in from the walls. Strictly talking about mitigating heat coming from human body.

Basically, If I wore some weird suit that directly cooled my body, I would theoretically only need one 500BTU/hr air conditioner to satisfy the cooling requirement.

Yes, when performing a load calculation for locations, occupancy plays a huge part of the calculation, as does situation.
Restaurant capacity is a lower btu/person than dance club capacity...

 

[curiouscarbon]

Stillsuit

A stillsuit is a full body suit worn in the open desert of the planet Arrakis that was designed to preserve the body's moisture. It consisted of various layers that would absorb the body's moisture through sweating and urination, and then filter the impurities so that drinkable water would be...

dune.fandom.com

 

[RogerD]

Vacuum Insulated Panel

12 x 12 x 1 inch

R20

that’s a building block I plan on using to reduce thermal conduction between spaces

https://www.digikey.com/en/products/detail/panasonic-industrial-devices-fbd/TZB7880E/9558505

bought a few of these ^ panels to play with. they are made by wrapping a hollow fiberglass core with a sheet of mylar and pumping much of the air out and then sealing it. the lack of Air Inside The Panel reduces internal radiative transfer.

direct conduction still occurs near the edges.

they need padding to protect against mylar puncture which would introduce air back into the panel and reduce the insulation value from R60 at center, R20 average down to R5.

R20 in one inch is fricking good in my humble opinion.

I recently started looking into Vacuum Insulated Panel for an SUV build I'm doing and came across the same page.

What I don't understand is that regardless of the panel size at whatever thickness the center R-value is the same. One inch is 60 at the center for example. However, the effective R-value is much lower and varies based on the size of the panel. Larger panel - higher R-value. Smaller panel - lower R-value.

Why does the R-value vary based on size?

What exactly is effective R-value.

 

[curiouscarbon]

The fiberglass shell that has mylar wrapped around it to construct the Vacuum Insulated Panel conducts heat itself. It’s hollow in the center, that’s where the vacuum protects best. The edges are necessarily filled in and this reduces the insulation performance there.

The specific R value lowest near the edge because fiberglass direct conduction. Placing the center of the panel over something hot is the design directive that results from this.

Basically, if you have a hot spot on the outside (black patch of paint?) then you would want to place the Vacuum Insulated Panel so that the center of the panel is placed directly on where it’s hottest.

It can be R60 in the center the edge are much lower and average out to R20. Near the edges it behaves more like normal high end foam insulation. Near the center is where it performs best. The insulation value is not uniform throughout the material as one is accustomed to with foam.

Hope this helps @RogerD, good luck with your experiments and please share whatever you feel like!

one last thing.. i read that if the vacuum is lost/punctured the R value becomes something like R5. So you can imagine that the fiberglass itself is not such a great insulator without the vacuum. This is why padding the Vacuum Insulated Panel and protecting it from sharp objects from preparation to installation is critical for proper thermal performance.

 

[curiouscarbon]

Why does the R-value vary based on size?

What exactly is effective R-value.

it varies based on size because the vacuum void space in the center of the panel scales up. and by volume the void space dominates the volume taken up by the fiberglass.

effective R-value = average of local/spot R-value across entire face of panel. highest in center gradually becoming lowest on edges and corners.

with foam panels, this value is generally uniform throughout the material.

 

[curiouscarbon]

What I don't understand is that regardless of the panel size at whatever thickness the center R-value is the same.

It is the same because if you think of taking a cookie cutter to the panel you’ll find that at the center of the panel, the common thing is that there are no walls on the cookie.

At the edges this breaks down and you start to get walls included in the cookie. Then it’s a combination of fiberglass R value and raw Vacuum R-value.

Sorry if I spammed too much, this topic is very interesting to me as well and navigating the topic of R value and thermal conductivity has kept me on my toes so to speak.

 

[RogerD]

@curiouscarbon

Thanks for the input. Vacuum Insulated Panel is not a solution for what I'm looking to do.

 

[MAGE]

Together we will solve the climate control crisis. Spam away!

I’ve decided to go with the ICECO 60QT 3 in 1 since it’s on Indiegogo for $499. Gonna pack it to the brim with ice and run an aluminum pipe from my dads scrap metal for initial testing but it won’t arrive until October lol. O well. It would be $800 normally but I’m gonna early bird it up

In the meantime I’ll be messing around with some cheaper coolers and stuff...

 

[curiouscarbon]

i think the appeal of a box with tubes and ice is becoming more apparent to me.

if there’s enough electricity, pump heat through the freezer’s compressor

if there’s no electricity but enough money, buy a bag of ice and dump it in.

am i following properly? this use case sounds like it could be helpful for people with lower end van setup?

 

[MAGE]

Yep you got it curious! I've seen those types of setups run for a few days if the box is big enough, and considering I'm getting the big one from ICECO i'm really excited to see if I can make the ice last for....ever....

I plan to run the 4" fan and convert the aluminum tubing down to 3" as it will be made to run throughout the bottom of the ICECO and then come back out facing forward. I hope the ICECO heat outbput on the bottom can be easily pointed towards the cab and allow me to easily open it. I do think it's going to come down to me building my own custom lid to allow for the tubing to enter and exit one side and allow me to open up the other side for the food etc...

I settled on getting the Bluetti Maxoak 1500W since they're $999 now with the discount and because they allow for up to 400W solar charging. I'm getting around a 340 watt all black solar panel which will be compatible with the cable that comes with the bluetti. I'm going with all black for ultimate stealth mode since my Odyssey is dark grey and I want the black on the top not to look like a typical solar panel and someone just walking by won't even notice a solar panel up there, since it will be all black

 

[curiouscarbon]

combined food storage and air cooling is certainly an unexpected combination for me; the fundamentals seem sound of buffering compressor with specific heat capacity of water.

wishing you well with your HVAC experiments!

 

[MAGE]

Thanks! Yep I’m going to continue to post on this thread for all ideas of maximum efficiency and optimal products. I got an email back from Pecron so I’m actually wondering if I should go with the Pecron instead of the Bluetti. The Bluetti has an MPPT charge controller built in and the Pecron does not. But I did get a message back from Pecron yesterday. Here’s what it says

So now I’ve been looking for a 350 watt solar panel which can meet these requirements. The Pecron only weighs 27 lbs but the Bluetti weighs 65lbs. Considering I want to add a little weight and space as possible I’m actually leaning towards the Pecron now but finding the solar panel type I want seems like more of a challenge. I only want 1 panel (black).

 

[MAGE]

 

[MAGE]

That last post I made was for reference of how much solar is needed per BTU

here’s a guy that did it for a van. What a champ.

 

[curiouscarbon]

That last post I made was for reference of how much solar is needed per BTU

here’s a guy that did it for a van. What a champ.

finally watched this, really inspired design methinks.

thank you for sharing

 

[Evado]

There is another solution :