(SOLVED) Solving the climate control crises

[MAGE]

Looks like the solar voltage has to be more than 45 volts won't work with the LG solar panels...if anyone has any recommendations for a 300+ solar panel compatible with this solar generator lmk...

 

[noenegdod]

There's other variables at play, what climate are you in? Are you in the desert where evaporative cooling is quite effective but requires a ready supply of water, or are you in hot / humid climates where you need active moisture removal? My personal suggestion is to use an inverter based AC unit, in particular the Midea 8k BTU U-style window unit. I have the same unit in my room that Will has in his. These AC units are awesome. These have a "special" feature in them as they use their condensation to sling water onto the condenser coils getting a little boost in performance that no other AC unit (outside of water slinging window units) can obtain. The best part of this is that you can boost performance on-demand, (1)just dump in 20oz of filtered water.

All AC units have curves showing their capacities. (2)The hotter the inside and outside temps, the less cooling capacity they have. This plagues all units, there's no way around this. However, having a unit that can utilize condensate to hack the curves drastically changes things. Suddenly a 100 degree day isn't a 100 degree day for the AC unit that's able to utilize evaporative cooling on its condenser. It gets a huge bump in efficiency / capacity. You can apply this hack to other AC units by way of a mist system, but you must use (1)filtered water to feed it as mineralization and bleach are bad for units. (3)AC units that are simply on or off (traditional) don't really get a bump in power usage realm, just the frequency at which they turn on and off (saving total usage power, but not running power). For inverter units on the other hand, the computer will see it's doing a great job and can slow down the pump thus using less energy to produce the same amount of cooling.

The window units are gravity drained like all window units and need to have the rear lower than the front. Not drastically, but a condition that must be met at all times during operation. There's no easy inside (as of from the inside portion of the unit) way of adding additional water to them, but a 1/4" line could be run to them where you can periodically turn on water to fill its basin. As mine is a window unit, and the benefit of these as window units allows you to retain opening the window, I just open the window and dump in some water if I want a boost in capacity. I envision these being installed in-place and then closing in the pass through. (google midea U inverter ac if you're not sure what they are, and what I mean by closing it back up, see crude drawing attached)

I am just going to point out a few errors to prevent misinformation.

1."Filtered" water. What most people think of when you say "filtered" is not acceptable. It must have a TDS of 0 PPM if it is going to be used in this application with any frequency. The only acceptable "filtered water" would be water that has traveled through an RO fliter and then through a demineralizing cartridge to remove the last 5% TDS. Distilled would be the only other option.
Running an element type humidifier is another way to introduce solids free water into the air that will then condense on the evaporator and then to the condenser to help reject heat.

2.The colder the inside and hotter the outside temps, the less cooling capacity any given unit has. Its all about pressure differential between the 2 coils and the hotter the condenser coil (outside temp) and colder the evaporator coil is (inside temp), the harder the compressor has to work.

3. This is not correct. Regardless of whether they cycle on and off or vary their output, they both see the exact same benefit. The colder the condenser coil is the less power they consume. Also, the greater the temperature difference between the two coils, the greater the proportion of the coolant is required to flash to simply get the incoming refrigerant down to condenser temp. Another loss regardless of type of compressor/drive helped by evaporative cooling on the condenser side.

 

[HammaMan]

I am just going to point out a few errors to prevent misinformation.

1."Filtered" water. What most people think of when you say "filtered" is not acceptable. It must have a TDS of 0 PPM if it is going to be used in this application with any frequency. The only acceptable "filtered water" would be water that has traveled through an RO fliter and then through a demineralizing cartridge to remove the last 5% TDS. Distilled would be the only other option.
Running an element type humidifier is another way to introduce solids free water into the air that will then condense on the evaporator and then to the condenser to help reject heat.

2.The colder the inside and hotter the outside temps, the less cooling capacity any given unit has. Its all about pressure differential between the 2 coils and the hotter the condenser coil (outside temp) and colder the evaporator coil is (inside temp), the harder the compressor has to work.

3. This is not correct. Regardless of whether they cycle on and off or vary their output, they both see the exact same benefit. The colder the condenser coil is the less power they consume. Also, the greater the temperature difference between the two coils, the greater the proportion of the coolant is required to flash to simply get the incoming refrigerant down to condenser temp. Another loss regardless of type of compressor/drive helped by evaporative cooling on the condenser side.

No, you don't need that level of filtration. Zero water's filtration level is plenty -- I use britta activated carbon filtered water. The moisture in your air is not 'just' moisture. It's got all kinds of things in it, the AC unit itself also has dust and pollen in it (we've got red clay dust around here, it's full of iron). The unit will be replaced before there's even remotely any issue using brita / zero water level of filtration. Distilled waters only uses are medical / lab. Don't need it in batteries, don't need it in radiators, just filter it as described and it's PLENTY. 2 decades doing this stuff with activated carbon filtered water -- no issues. Don't use softened water, and don't use excessively hard water.

 

[noenegdod]

No, you don't need that level of filtration. Zero water's filtration level is plenty -- I use britta activated carbon filtered water. The moisture in your air is not 'just' moisture. It's got all kinds of things in it, the AC unit itself also has dust and pollen in it (we've got red clay dust around here, it's full of iron). The unit will be replaced before there's even remotely any issue using brita / zero water level of filtration. Distilled waters only uses are medical / lab. Don't need it in batteries, don't need it in radiators, just filter it as described and it's PLENTY. 2 decades doing this stuff with activated carbon filtered water -- no issues. Don't use softened water, and don't use excessively hard water.

Sorry buddy but that is flat out wrong. You can do it and I really dont care how you treat your equipment but recommending others do it is a different story.
The moisture in the air doesn't have anything of consequence "in it". Its a gas. There is some garbage floating along with it but the calcium and magnesium (which is the issue) that is in regular tap water was left behind when it phase changed from liquid to gas. The water in the air is literally distilled water, it is just contaminated with dust and other garbage that easily washes off the condenser. The problem with using water with dissolved solids in it is that Calcium and magnesium chloride does not wash off easily at all. It requires a low ph to dissolve it. Using CLR or a similar product isnt good for aluminum or copper which you condenser is made of. Having even a thin layer of solids on the coil has a substantial impact on heat transfer making evaporative cooling a necessity to recover this loss.

If you are going to use tap water run through a britta (shakes head), do use water that has been softened. Water that has been softened has had its calcium and magnesium ions exchanged for sodium. Instead of calcium and magnesium chloride, Sodium chloride is the solid that will build up on you coils and is much easier to wash off.

 

[MAGE]

Just wanted to check with you guys and ask if 3 of these Harbor Freight panels in series will be compatible with the SungTzu 2500. I finally found this youtube video that lets me see the specs of the panel.

18V-24 VDC Harbor Freight Panels. The SungTzu is rated for 45VDC ~ 80VDC at 500 Watts.

It was hard to find the specs on the Harbor Freight site but I did find them in the youtube video.

100 Watt Monocrystalline Solar Panel

Amazing deals on this 100W Solar Panel Monocrystalline at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

Does anyone know what cables I would need to set all 3 of these panels up in series? Will I need the $21 charge controllers as well? I can actually go pick these up at Home Depot where I live lol...

I picked these because they will be easy to fit on my Odsyssey

 

[Supervstech]

Just wanted to check with you guys and ask if 3 of these Harbor Freight panels in series will be compatible with the SungTzu 2500. I finally found this youtube video that lets me see the specs of the panel.

18V-24 VDC Harbor Freight Panels. The SungTzu is rated for 45VDC ~ 80VDC at 500 Watts.

It was hard to find the specs on the Harbor Freight site but I did find them in the youtube video.

100 Watt Monocrystalline Solar Panel

Amazing deals on this 100W Solar Panel Monocrystalline at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

Does anyone know what cables I would need to set all 3 of these panels up in series? Will I need the $21 charge controllers as well? I can actually go pick these up at Home Depot where I live lol...

I picked these because they will be easy to fit on my Odsyssey

Harbor freight stuff is designed to work with their pwm controllers, and are not designed to be run in series.
To use them in series, may require diodes be installed etc…

windy nation panels are same price, and easily operate in series, come with mc4 connections, and have a track record.

 

[MAGE]

I need panels where the dimensions fit on my van inside the racks. 38.5 is the max and I need another couple inches for the mount pieces. How about Grape panels from Harbor Freight?

 

[MAGE]

Maybe 4 of these will work!

75W 12V Monocrystalline Solar Panel

Newpowa 75W Mono 12V Solar Panel is ideal for harvesting energy to power small electronics. This module is commonly paired with RV, marine, gate opener, traffic signals, and various off-grid applications. Top branded, 2 years warranty, Free Shipping!

www.newpowa.com

 

[Homeless HVACtechTX]

I've been in the HVAC industry for 30 years. The first step to increasing efficiency of an HVAC system is to minimize the load as much as possible. If sun is hitting any part of an RV, it will heat the RV quickly. Try to block sun from hitting the RV, especially in the less insulated areas like the door. Parts of the RV that must receive sun should be painted white or have a highly reflective coating. (Set white and black objects in the sun and feel the difference) Next, you should make sure to seal ALL air leaks from inside to outside air wherever possible. This mostly partains to older RVs. An air compression test might need to be conducted to find as many leaks as possible. Last but not least, make sure to insulate any areas that might transfer heat to inside the RV. Insulating and making the RV airtight will help cooling and heating efficiency. I know people like to mount panels to the top of RVs, but I personally believe that having the RV in shade is much more useful in very hot climates. I also know that it's not always an option to park the RV in shade, but RV parks need to consider the power consumption of their tenants. Reducing the heat load is the most cost effective way to increase cooling efficiency and lower the demand on the cooling system as well as your power source.

 

[MAGE]

 

[curiouscarbon]

Body Cooling Vests | Personal Air Conditioner System

Keep your employees cool & comfortable in extreme temps with personal body cooling vests.

www.vortec.com

Vortec Dual Action Personal Air Conditioner Protects Workers in both Hot and Cold Environments

Cincinnati, OH (PRWEB) February 13, 2013 -- Workers can now easily fend off the effects of working in extreme temperatures resulting in increased productivity,

www.prweb.com

alert: not practical for most

personal body cooler with vortex tube.

1500 and 2500 BTU/hr ratings

 

[robby]

I love the enthusiasm in this thread but I am not really seeing any hard numbers for this project.
If your going to start something like this you need to know what the Temperature and humidity of the Van is in the day and the night on a typical or better yet worst case day without any cooling system and then you need to know the amount of area that requires cooling. These are things one needs to know just to see if it is even an achievable goal.

It's a real stretch to imagine being able to mount enough solar cells on a Van to not only run the system during the small 5 hour window of good solar production but also charge the batteries enough to go through the remaining hours that the AC will be on.
Cooling the AC condenser coils with regular water is a terrible idea as pointed out by @noenegdod as you will be battling calcium and other mineral build ups on a monthly basis. Using RoDI water is also a bad idea as it is highly corrosive to metal and just about anything else it comes in contact with. RoDi water is so pure that it is desperately trying to strip away atoms from anything it comes in contact with. I doubt your coils would last a year before they are oxidized to the point of leaking gas! The use of distilled or plain RO water with a TDS of 5-10 would be your best bet. Once again you run into loads of problems on practicality versus the results you will achieve.

Using Ice is another one of those things that just seems to be really impractical unless you can get Ice for free and the supply is close by. The advice about using good insulation and super efficient items and blocking as much sunlight is one of the best ideas to start achieving any kind of good result but is that something that is possible for you to do.

Honestly I think this is one of those free energy type ideas if your Temperature Delta required is too high. If the heat that is needed to be removed is small then maybe it can work with panels and a very small AC system and some good LIPO4 battery packs.

 

[MAGE]

The latest plan is to modify the new 60QT ICECO which will be plugged into the 2024Wah Leoch running on 300 watts of solar from 3 100 watt HQST panels in parallel. I’ve settled on the Leoch for now since it’s LifeP04 and has 300 watts solar input. It also has two AC wall chargers that I can just run on an inverter when I’m driving or can run the engine plus the solar if I need a faster charge. I expect the ice to melt at some point in which case I can shut the duct fan attached to the aluminum pipe/duct running through the bottom of the ICECO. I’ll have to wait until November for all of this stuff to be shipped to me lol.

 

[noenegdod]

Using RoDI water is also a bad idea as it is highly corrosive to metal and just about anything else it comes in contact with. RoDi water is so pure that it is desperately trying to strip away atoms from anything it comes in contact with. I doubt your coils would last a year before they are oxidized to the point of leaking gas!

Thank you for pointing that out. I kind of forgot about that.

You can use deionized water for evaporative cooling but you have to do it right. Liquid water cannot come in contact with the coils. It needs to evaporate fully and cool the air, then travel through the coils as a gas

6 houses ago I built a cooling tower for a conventional residential AC unit. It was 9' tall, the ac unit sat in side it at the top and the walls of the tower were 12" from the sides of the ac unit. 12" of the bottom of the tower were open for air to enter and just above the open sides (inside the tower) was a motor with a spinning disk that RO water dripped on. It would use ~5 gallon of water/hr. There was really no visible corrosion on the disk after 5 years and the AC coils looked fine. The waste water from the RO was used to water the lawn so it wasnt a waste. It should also be pointed out that this works well in a dryer climate. You wouldnt waste you time or money doing this in a humid climate.

Having typed all this, I Just realized I did not have a demineralizing cartridge in this system so TDS was probably in the 5-15 PPM range anyway. 25 years ago demineralizing cartridges were not readily available to consumers.

 

[toms]

An option that is being used in trucks in Australia is the all in one LiNMC / DC split system aircon.
Check out:

Truck Sleeper Cab Cooling System | Coolabah DCAC | Our Unit

Sydney's finest sleeper cab cooling system fitters. Solely powered on lithium batteries, the Coolabah DCAC makes a statement in a class of its own.

www.coolabahdcac.com

for more details.

 

[curiouscarbon]

A research paper reminded me of this thread.

Numerical Simulation of Internal Melt Ice-on-Coil Thermal Storage System​

The main purpose of this paper is to simulate the charging and discharging process of internal melt ice-on-coil thermal storage system
Its mathematic model is built and the results of the simulation and experiment are compared for verifying the simulation.

 

[acdoctor]

You may need a lot of ice. A “ton” is one of the most important terms to know, because it is the way in which air conditioning units are measured. A ton represents the total cooling capacity that an AC system has to offer. One ton is equivalent to how much heat is required (288,000 BTU) to melt one ton of ice over the course of 24 hours.

 

[Hedges]

Not so much.
1 ton = 2000 lbs. 1 gallon = 8 lbs. 1 ton = 250 gallons.
1 cubic foot = 8 gallons. 1 ton = 31 cubic feet. A bit over 3' cube, about 1 meter cube.
So a couple cubic meters of ice should hold a days air conditioning?

Seems to me it is easy to extract cold with melting, because icewater flows. Harder to freeze, ice has some insulating value. Need tubes or fins spanning much of the volume. Maybe a serpentine sheet of aluminum, joined to a refrigerant tube.

 

[rcrracer]

that sounds delightfully frustrating! i’ve heard many sad stories of single tube type and the way they pull hot air from outside to move air.

if a dual hose type is properly configured, i would assume it should be better behaved than the single tube type.

but i only have experience with Dual Tube and U shaped (midea) so far.

definitely would want to place the hot condenser outside to begin with

i’ve also read about corrosion of the condenser coil when it’s used to evaporate condensate, in models that do not have some anti corrosion coating such as epoxy

i’m still seriously considering building my own device from parts using water and corn glycol as heat exchange work fluid.

https://www.amazon.com/AB-Exchanger-Heating-Outdoor-Furnace/dp/B07BB26LGF

easier for me to engineer a pleasant mount for that thin radiator than a mini split

of course this isn’t for everyone, don’t overcomplicate! but i sure as heck like DIY so it’s important for me to mention for other DIY minded HVACkers

Midea now has a two hoser, inverter technology, with compressor heat. https://www.amazon.com/Midea-Conditioner-Dehumidifier-sq-ft-works-Assistant/dp/B091CKVY9F
It is re-branded as a Toshiba, which is white and about $100 cheaper.
Single tube portables make a low pressure inside the house which sucks in the outside hot air.

 

[rcrracer]

A research paper reminded me of this thread.

Numerical Simulation of Internal Melt Ice-on-Coil Thermal Storage System​

View attachment 60593
View attachment 60594

Ice Bear® Storage Module

Thermal Energy Storage for Light Commercial Refrigerant-Based Air Conditioning Units

www.energy.gov