How many solar panels

[RidgeTopWVA]

How many solar panels would it take to run a window air conditioner ?

 

[2manyrocks]

Will Prowse and CheapRV Living have a couple of youtube videos on this. Depends on the size of the window unit and how much start up power is required. The solar panels are relatively cheap. The storage batteries aren't.

 

[sea2summit]

Maybe only one of you have a big enough battery and you don’t want to run it often. If you mean how many will it take to run the AC directly from the panels, that’s almost impossible. Each panel only produces about .5 volts with varying watts depending on the size of panel. Really hard to get the power you need without a battery (bank) as ACs have pretty significant starting draws and are fairly power hungry in general.

 

[bnold]

Maybe only one of you have a big enough battery and you don’t want to run it often. If you mean how many will it take to run the AC directly from the panels, that’s almost impossible. Each panel only produces about .5 volts with varying watts depending on the size of panel. Really hard to get the power you need without a battery (bank) as ACs have pretty significant starting draws and are fairly power hungry in general.

0.5V??

Panels on my shop at 44VDC open circuit, 37VDC loaded.

Each string coming into inverter is ~ 530VDC open, 450VDC loaded

 

[sea2summit]

0.5V??

Panels on my shop at 44VDC open circuit, 37VDC loaded.

Each string coming into inverter is ~ 530VDC open, 450VDC loaded

Key word, panels. What is the cell voltage in your panels? It’s going to be between .5v and .6v. 37vdc is a sum of the output from the number of cells and number of panels. You obviously invested a lot in the system, so you probably understand this.

 

[RidgeTopWVA]

It doesnt sound feasible.

 

[Midniteoyl]

Key word, panels. What is the cell voltage in your panels? It’s going to be between .5v and .6v. 37vdc is a sum of the output from the number of cells and number of panels. You obviously invested a lot in the system, so you probably understand this.

You wrote 'panel' in your initial reply, instead of cells. Thats where the confusion came in.

Each panel only produces about .5 volts

 

[LittleBill21]

its actually been done for years... rv people do it all the time

here is the home version

DC Solar Air Conditioner Heat Pump | Solar Air Conditioning | Solar Heating | Manufacturers

 

[LittleBill21]

You wrote 'panel' in your initial reply, instead of cells. Thats where the confusion came in.

it doesn't matter, he's wasting people's time with his antics. no one gives a crap about cell voltage, as its completely irrelevant.

 

[sea2summit]

You wrote 'panel' in your initial reply, instead of cells. Thats where the confusion came in.

Grrrr, that's why you can't trust anything on the internet. Sometimes I iz we Todd did.

 

[dmccarty]

You cannot run the AC off the solar panels since any reasonable number of panels will not have enough watts. One would have to use solar panels to charge batteries which could then run the air conditioning.

The other problem is that solar panels produce DC power, and the air conditioning will need AC power, so an inverter will be needed. Then there is the startup power that is needed but there are ways to handle that requirement.

Even a small window air conditioning unit is going to use quite a bit of power, so a battery bank to run the unit will have to be quite large to run for a few hours. Regular lead acid batteries will require quite a few in the battery bank and they are large and heavy. If one used LiFePo batteries for the battery bank, the space needed, along with weight, is reduced, but decent LiFePo batteries are expensive. I would guess one would need at least a couple of batteries to run a very small AC unit for a couple of hours and these batteries are around $3,000 a piece.

Running air conditioning from solar panels is possible, but it is not cheap, and requires an inverter, solar panel battery chargers, a battery bank, etc., and one won't run the AC for long.

Then there is the issue of how many hours are there a day to charge the battery. In my area of NC, one gets about 5 hours a day winter and summer. If one goes farther north, they can get more hours during the summer but very little time in the winter.

 

[quicksandfarmer]

It doesnt sound feasible.

Are you grid-tied or off-grid? Does your utility offer net metering if you're grid-tied?

If you have net metering it's easy to do enough panels to cover air conditioning. If you're off-grid it gets more complicated.

 

[RidgeTopWVA]

Are you grid-tied or off-grid? Does your utility offer net metering if you're grid-tied?

If you have net metering it's easy to do enough panels to cover air conditioning. If you're off-grid it gets more complicated.

I was thinking about off the grid.

 

[RidgeTopWVA]

You cannot run the AC off the solar panels since any reasonable number of panels will not have enough watts. One would have to use solar panels to charge batteries which could then run the air conditioning.

The other problem is that solar panels produce DC power, and the air conditioning will need AC power, so an inverter will be needed. Then there is the startup power that is needed but there are ways to handle that requirement.

Even a small window air conditioning unit is going to use quite a bit of power, so a battery bank to run the unit will have to be quite large to run for a few hours. Regular lead acid batteries will require quite a few in the battery bank and they are large and heavy. If one used LiFePo batteries for the battery bank, the space needed, along with weight, is reduced, but decent LiFePo batteries are expensive. I would guess one would need at least a couple of batteries to run a very small AC unit for a couple of hours and these batteries are around $3,000 a piece.

Running air conditioning from solar panels is possible, but it is not cheap, and requires an inverter, solar panel battery chargers, a battery bank, etc., and one won't run the AC for long.

Then there is the issue of how many hours are there a day to charge the battery. In my area of NC, one gets about 5 hours a day winter and summer. If one goes farther north, they can get more hours during the summer but very little time in the winter.

WOW...thanks for info...

 

[quicksandfarmer]

The system linked to in post #8 is a good choice. Their page says they need a minimum of 1200 watts, which is about three panels. A one-ton (12,000 BTU) unit is $1895, most window units are about that size.

You just have to be OK with only getting cooling when the sun is out.

 

[RidgeTopWVA]

The system linked to in post #8 is a good choice. Their page says they need a minimum of 1200 watts, which is about three panels. A one-ton (12,000 BTU) unit is $1895, most window units are about that size.

You just have to be OK with only getting cooling when the sun is out.

If need be I can always get a generator for back up...

 

[LittleBill21]

If need be I can always get a generator for back up...

AS I said in post #8 this has been done for a while. There is a bunch of false info in this thread, that it can't be done. I personally know people with rv's doing it with batteries and solar, without issue.

Go on youtube and look for https://www.youtube.com/@engineer775

he routinely installs the unit I posted

 

[MAX-24-Dean]

its actually been done for years... rv people do it all the time

here is the home version

DC Solar Air Conditioner Heat Pump | Solar Air Conditioning | Solar Heating | Manufacturers

These are quality units. They were using Toshiba and/or Panasonic compressors in 2017.
They will answer your questions if you contact them.