Portable Electric Air Conditioning from Peter Schiff

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RCG571

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rcg571
Has anyone purchased any one of the Peter Schiff portable AC units? I have a 182Q and Texas summers are brutal and the wife is very negative about sweating till altitude. I've tried the Arctic Air evaporative coolers and they just aren't suited for my mission. Lugging ice around and then draining at destination is pain. Then more ice is required at destination to come home. Booo.

Seems I'll need to upgrade to a 100A alternator since my plane is 12VDC, but I can't find any other suppliers for a solution like this. Not being STC'd, portable, and removable for the cooler months is a big plus in my book.

Any feedback or direction would be appreciated.

Portable A/C | Peterschiffaero

www.peterschiffaero.com www.peterschiffaero.com
 
tangential question - would a portable battery like https://www.amerescosolar.com/simpliphi-phi-1-2-kwh-high-output-lithium-battery that has the energy (this example doesn't have a voltage match to the 12V plane) required to run the unit for ~1hr be cheaper than upgrading the alternator?

It "seems" like a battery powered unit for peak usage that is charged at a rate the existing alternator can handle would be a far easier installation and truly portable between different planes.
 
I started looking at electric only AC systems for my plane also. I sent a few emails to a different vendor because, I could never get the answers to the BTU calculations to work out with 12V 65amp power draw. The best I could determine with an 85% efficiency rating was about 2300BTU, but the vendor was advertising 8,000 BTU. They never got back to me with anything except marketing materials.

I'd like someone with HVAC expertise to walk through the power consumption vs BTU production of any elec portable AC systems. As an example, I had one of those old style boat AC that sits on the foredeck of a cabin boat. It was rated at 5,000BTU. Plugged in to a 120VAC outlet, and took 10.8amps running. That's 1300W for 5,000BTU. Hmmm, but the plane AC is rating it 8,000BTU?

I used this as just a handy quick way to figure it out.

BTU to watts (W) conversion calculator

BTU per hour (BTU/hr) to watts (W) power conversion calculator and how to convert.
www.calculatorx.com www.calculatorx.com

8000BTU/hr works out to 2344W/hr. Maybe I'm doing it wrong?
 
Barrett50 said:
I used this as just a handy quick way to figure it out.

BTU to watts (W) conversion calculator

BTU per hour (BTU/hr) to watts (W) power conversion calculator and how to convert.
www.calculatorx.com www.calculatorx.com

8000BTU/hr works out to 2344W/hr. Maybe I'm doing it wrong?
Click to expand...
That is reasonable to approximate the performance of an electric heater, which is converting electrical energy to heat energy.

That is not reasonable for your application. Because of the laws of physics (entropy), you can't directly convert electricity to cooling like you can to heating. (Even with piezoelectric devices.) Most cooling systems are just moving heat from one place to another. The energy required to do that is used in the motors driving the fans/pumps/compressors and there is not a universal relationship between power consumption vs. amount of heat transferred--it depends on the system design, working fluid, and environmental factors.
 
Jim_R said:
That is reasonable to approximate the performance of an electric heater, which is converting electrical energy to heat energy.

That is not reasonable for your application. Because of the laws of physics (entropy), you can't directly convert electricity to cooling like you can to heating. (Even with piezoelectric devices.) Most cooling systems are just moving heat from one place to another. The energy required to do that is used in the motors driving the fans/pumps/compressors and there is not a universal relationship between power consumption vs. amount of heat transferred--it depends on the system design, working fluid, and environmental factors.
Click to expand...
Right, that's what I had decided, so I used another method that takes into account the efficiency of the conversion. Typical AC units are 83% efficient. Some are a bit more than that, and some a bit less. However, even the best of the best cannot come close to the best case Carnot engine conversion. Which is why I used the quick and dirty calc above.

If we use an efficiency of 85%, the vendor is promising 8,000BTU/hr. And, what will that be in terms of W/hr? My example of the boat AC is indicative that the conversion offered by the vendor is wildly optimistic. Anything else that can be provided for the conversion relationship in Carnot(entropy) terms will be appreciated. The different vendor I contacted didn't know, or didn't want to disclose.
 
Barrett50 said:
Right, that's what I had decided, so I used another method that takes into account the efficiency of the conversion. Typical AC units are 83% efficient. Some are a bit more than that, and some a bit less. However, even the best of the best cannot come close to the best case Carnot engine conversion. Which is why I used the quick and dirty calc above.

If we use an efficiency of 85%, the vendor is promising 8,000BTU/hr. And, what will that be in terms of W/hr? My example of the boat AC is indicative that the conversion offered by the vendor is wildly optimistic. Anything else that can be provided for the conversion relationship in Carnot(entropy) terms will be appreciated. The different vendor I contacted didn't know, or didn't want to disclose.
Click to expand...
Again, apples and oranges. You're not directly converting electricity into "cooling" like some kind of a reverse heater. That's why you don't hear AC vendors talk about their units being "85% efficient" and instead talk about more esoteric measurements like "SEER".

If you want to look at home air conditioners as a comparison, there are a bunch of HVAC sites that will give you ballpark electricity usage figures. Here are a couple:
learnmetrics.com

How Much Electricity (kWh) Do Air Conditioners Use? (Calc + Chart)

How much electricity do air conditioners use? Quite a lot, actually. According to EIA, US households used 235 billion kWh (kilowatt-hours) of electricity just for cooling in 2021. Of course, we are usually most interested in how many kWh does our air conditioner use. Most of us already know that...
learnmetrics.com learnmetrics.com
www.renewablewise.com

How Much Electricity (kWh And KW) Does An Air Conditioner Use? | RenewableWise

But how much electricity does an air conditioner use exactly?
www.renewablewise.com www.renewablewise.com

Even a low-efficiency 8000 BTU system would draw less than 1kW, and a typical modern system would more likely be closer to half of that.

Now, whether it makes sense to draw any comparison between a home AC system and the portable you're looking at using in your aircraft is another question. But the point is, you gotta stop thinking about direct conversions between BTU and watts times some efficiency factor. You need to know more about the mechanism the system is using to move the heat around, and some are more energy-costly than others.
 
To add to what's been said above, an air conditioner can move more than twice the amount of heat energy compared to the energy they consume. That's why people use heat pumps instead of resistive heaters.
 
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What I need, and I think the OP needs is the ampacity draw. If the 182 has a 12volt system, it's going to be rated at 12.5VDC which is the nominal voltage of a FLA cell at 90% SOC. If we use an EER of 12 which is a SEER(I don't need the seasonal, all I care about is the worst case summer number) of 13 - 14. We'll say it uses 850W, just to be safe, that's 850/12.5V = 68 amps. Finally something useful.

If we use the 80% rule for alternator loads, then a 68 amp draw by the AC would leave 32 amps left over for the remainder of the alternator output of 100 amp rating. However, the AC unit is advertised as being 'portable' and thus not subject to the 80% rule for aircraft alternator output. A plane with a 50A alternator would not work at all. A plane with an 80A alternator would work - barely and leave very little reserve for other loads on the plane.

For 68A load, we need 4Ga, or 2Ga wire would be better. The vendor says 35-75 amp draw for 12V system. It's doable, but I wouldn't want to try it on a 80A alternator. The time the AC is needed is on the ground, and on takeoff/landing. I'm going to need the 100A alternator, if there's an STC for that, and then add the big power cables from the batt to the AC unit.
 
I have an Ecoflow Wave 2 in my Mooney. It's not as effective as a car AC but, it's good enough to keep you from sweating during ground ops and climb out. Coupled with some static cling tint on the windows, it does a decent job.

I'm near San Antonio so, I understand Texas summers.

Sent from my Pixel 9 Pro XL using Tapatalk
 
I’m looking for an AC option for my 182 P. Seems there are options for 24 volts systems, but mine is a 12 volt. No engine driven compressors are available. I’m thinking a removable/portable AC unit is probably my best option, given the lack of STC options for a permanent installation.

This is interesting. As it has its own battery it can run while engine is at idle / taxi speed on ground or even pre cool before engine start. It can be re charged via 12 volts, when engine is making power at cruise, etc.

www.zerobreeze.com

[Pre-order] ZERO BREEZE Mark 3 AC

Meet ZERO BREEZE Mark 3, the most powerful portable AC yet. With 5,280 BTU cooling power and weighing under 22 pounds, it’s perfect for spaces up to 150 square feet. Set your ideal temperature between 61°F and 88°F and enjoy unmatched climate control wherever you go.
www.zerobreeze.com www.zerobreeze.com
 
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I think GA aircraft would benefit most from cooled/ventilated seats. Low power consumption with quicker results and no swampy back. It shouldnt be hard to use ducted foam, pc type fans and breathable fabrics to keep your keister cool without adding yuuge current demands to our primitive electrical systems. You could even take advantage of the 100mph+ wind blowing a few inches away to cool your seat. I'm working on ideas for my pickup, which has AC that blows plenty of frigid air at my face...but I still have a swampy back!
 
bcg-63M20C said:
I have an Ecoflow Wave 2 in my Mooney. It's not as effective as a car AC but, it's good enough to keep you from sweating during ground ops and climb out. Coupled with some static cling tint on the windows, it does a decent job.

I'm near San Antonio so, I understand Texas summers.

Sent from my Pixel 9 Pro XL using Tapatalk
Click to expand...
Interesting. I’ve never heard of it but it looks like a decent option. I’m in Puerto Rico and the heat and humidity have sapped some of my enjoyment of flying. I’ll have to look into it more.
 
Wrench978 said:
Interesting. I’ve never heard of it but it looks like a decent option. I’m in Puerto Rico and the heat and humidity have sapped some of my enjoyment of flying. I’ll have to look into it more.
Click to expand...

We have something similar in our 172 in the SAT area. Turn it on before you start the preflight and by the time you takeoff it’s tolerable.

You’ll likely need to find a way for the drain tube to make its way to the exterior and a way to vent the exhaust to the empennage so you don’t recycle hot air.

We went with a competitor simply because the Ecowave is bluetooth driven and one we got was an RF remote so we didn’t risk interference with the audio panel and transponder BT networks.
 
I run a Peter Schiff A/C in one of my planes. Very impressed with the little unit. It blows hard and has moderately cool air, the fan pushes a great deal of volume so for my that makes up for temperature.

In a 182, it will do really well, however it will eat up a little room. At least the version I have is about the size of a case of wine roughly.
 
Skymac said:
I run a Peter Schiff A/C in one of my planes. Very impressed with the little unit. It blows hard and has moderately cool air, the fan pushes a great deal of volume so for my that makes up for temperature.

In a 182, it will do really well, however it will eat up a little room. At least the version I have is about the size of a case of wine roughly.
Click to expand...
What kind of venting do you have for the compressor/condenser coils? Outside air in to cool the condenser cools, vent the hot air into the tail? How do you vent the condensation from the evaporator coils?
 
I have a factory installed a/c unit.
door.jpeg
 
WDD said:
What kind of venting do you have for the compressor/condenser coils? Outside air in to cool the condenser cools, vent the hot air into the tail? How do you vent the condensation from the evaporator coils?
Click to expand...

I’ll take photos today when I head out to fly and post them.

You don’t have to use fresh air in I don’t believe but they modified the plane for ducts in and out.
 
Skymac said:
I’ll take photos today when I head out to fly and post them.

You don’t have to use fresh air in I don’t believe but they modified the plane for ducts in and out.
Click to expand...
Much appreciated. I have a 182, and as a "transplanted Yankee with a U Haul" living in Atlanta, I do appreciate AC. I built an ice chest AC cooler that helps a lot, but is limited in how long it lasts, takes up a lot of the back seat, have to schlep a 5 gallon bucket of ice each time I use it, etc.
 
22c633201181c1efd44244ae575842bb.jpg
 
Sorry it took me a few days to remember, this is the Sofie Lite. unit.
 
It has 5 different names but more recently it’s a PAC E350 Expedition. They are a beast of an airplane! I’m very fond of it, just expensive like everything else these days. For me it’s a working plane, but I fly it XC all over the Southeast. 315HP / 142TAS and stalls around 45kt’s.
 
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