DC solar AC unit

[ub2slow2]

Does anyone have info on what a good brand/setup for a DC solar AC unit and cost? The one I’m looking at is a 12,000 BTU with (3) 340 watt panels, (4) 12V battery bank with charger controller for $4,200. Claim 9-10 hours run time with optimal sun and 4-5 hours run time at night off the batteries.

what do you all think of this package or are there better options you have experience?

 

[GMB]

That seems like a lot of $ for what you are getting. Do you have a link to this package so we can view all the details?

 

[ub2slow2]

That seems like a lot of $ for what you are getting. Do you have a link to this package so we can view all the details?

yes, here it is. Thank you

Solar DC Air Conditioning Systems

 

[GMB]

yes, here it is. Thank you

Solar DC Air Conditioning Systems

This is what they have listed on their website:

$1995 $ 800 $ 352 $ 790 $ 299 $4236

DC Solar Air Conditioner 12000BTU 3 x 340W PV Panels 3-panel Flush Mount Rail Kit (72C3) 4 x Trojan SCS225 12V 130AH batteries 1 x PWM Charge Controller ~Total System Estimated Cost *Wiring & connection materials not included. Includes estimated battery cost of $790, batteries supplied by customer and are not shipped or billed by HotSpot.

-You can obtain solar panels much cheaper than this. www.santansolar.com has new and used panels and craigslist may be on option in your area.
-Mounting can be done in a variety of cost saving ways including using super strut from your local big box store. Youtube has a lot of examples of ways to mount panels.
-$299 for a PWM charge controller is high and they don't mention the brand. You can obtain a top of the line Victron MPPT from Amazon or baymarinesupply.com.
-The batteries are lead acid in this example. Most here use LiFePO4 (Lithium Iron Phosphate). With lead acid you can only use about 50% and LiFePO4 you can use up to 100% (90% recommended). So they list four 12 volt batteries to make a 48 volt bank at 130ah. That equals about (48x130) 6240 watt hours. Now divide that 1/2 and that is around the actual usable watt hours, so 3120 watt hours. The spec sheet for the AC unit says it uses about 500 watts per hour under "normal" cooling conditions. So maybe about 5-6 hours of use when there is no sun. They mention that they do not sell these batteries and it's just an estimate, but they carry AGM batteries for sale. So you could supply your own here.

They also note that wires, fuses, shipping, etc are not included in this price. So you're probably realistically looking at around $5000.

I built out my system to run a 12,000 BTU portable AC unit and several other devices. It cost about $5700 and is about 3.5x as large as the one they list, but a lot of the cost is the AC unit in their estimate and mine was only $450. I assume that is a decent AC unit to cost that much.

I don't have experience with DC only AC units, so hard for me to give any advice here. Suggest reading reviews and buy the AC stand alone and build a system around it to save money. Will did a recent series on him running an AC unit in his shed that might help. It's rated at 440 watts, so right around what the one you listed uses. He uses all in one units and that save a lot of money as well, but do have drawbacks (fan noise, high idle consumption).

If you had this solar system, would it be just to run an AC unit or do you have a need for it to run other devices as well? Where is the AC being installed (garage, tiny home, etc.)?

My system as an example:

 

[RCinFLA]

Does anyone have info on what a good brand/setup for a DC solar AC unit and cost? The one I’m looking at is a 12,000 BTU with (3) 340 watt panels, (4) 12V battery bank with charger controller for $4,200. Claim 9-10 hours run time with optimal sun and 4-5 hours run time at night off the batteries.

what do you all think of this package or are there better options you have experience?

Put in a Grid tie system if you have grid. You will have to deal with permitting and approval outside of air cond install.

If you are truely off grid then battery is an option but expensive as the starting current requires a large inverter. There may be some things to help reduce startup current.

 

[ub2slow2]

This is what they have listed on their website:

$1995 $ 800 $ 352 $ 790 $ 299 $4236

DC Solar Air Conditioner 12000BTU 3 x 340W PV Panels 3-panel Flush Mount Rail Kit (72C3) 4 x Trojan SCS225 12V 130AH batteries 1 x PWM Charge Controller ~Total System Estimated Cost *Wiring & connection materials not included. Includes estimated battery cost of $790, batteries supplied by customer and are not shipped or billed by HotSpot.

-You can obtain solar panels much cheaper than this. www.santansolar.com has new and used panels and craigslist may be on option in your area.
-Mounting can be done in a variety of cost saving ways including using super strut from your local big box store. Youtube has a lot of examples of ways to mount panels.
-$299 for a PWM charge controller is high and they don't mention the brand. You can obtain a top of the line Victron MPPT from Amazon or baymarinesupply.com.
-The batteries are lead acid in this example. Most here use LiFePO4 (Lithium Iron Phosphate). With lead acid you can only use about 50% and LiFePO4 you can use up to 100% (90% recommended). So they list four 12 volt batteries to make a 48 volt bank at 130ah. That equals about (48x130) 6240 watt hours. Now divide that 1/2 and that is around the actual usable watt hours, so 3120 watt hours. The spec sheet for the AC unit says it uses about 500 watts per hour under "normal" cooling conditions. So maybe about 5-6 hours of use when there is no sun. They mention that they do not sell these batteries and it's just an estimate, but they carry AGM batteries for sale. So you could supply your own here.

They also note that wires, fuses, shipping, etc are not included in this price. So you're probably realistically looking at around $5000.

I built out my system to run a 12,000 BTU portable AC unit and several other devices. It cost about $5700 and is about 3.5x as large as the one they list, but a lot of the cost is the AC unit in their estimate and mine was only $450. I assume that is a decent AC unit to cost that much.

I don't have experience with DC only AC units, so hard for me to give any advice here. Suggest reading reviews and buy the AC stand alone and build a system around it to save money. Will did a recent series on him running an AC unit in his shed that might help. It's rated at 440 watts, so right around what the one you listed uses. He uses all in one units and that save a lot of money as well, but do have drawbacks (fan noise, high idle consumption).

If you had this solar system, would it be just to run an AC unit or do you have a need for it to run other devices as well? Where is the AC being installed (gar
Damn thank you so much. That was very helpful for sure!!

This is what they have listed on their website:

$1995 $ 800 $ 352 $ 790 $ 299 $4236

DC Solar Air Conditioner 12000BTU 3 x 340W PV Panels 3-panel Flush Mount Rail Kit (72C3) 4 x Trojan SCS225 12V 130AH batteries 1 x PWM Charge Controller ~Total System Estimated Cost *Wiring & connection materials not included. Includes estimated battery cost of $790, batteries supplied by customer and are not shipped or billed by HotSpot.

-You can obtain solar panels much cheaper than this. www.santansolar.com has new and used panels and craigslist may be on option in your area.
-Mounting can be done in a variety of cost saving ways including using super strut from your local big box store. Youtube has a lot of examples of ways to mount panels.
-$299 for a PWM charge controller is high and they don't mention the brand. You can obtain a top of the line Victron MPPT from Amazon or baymarinesupply.com.
-The batteries are lead acid in this example. Most here use LiFePO4 (Lithium Iron Phosphate). With lead acid you can only use about 50% and LiFePO4 you can use up to 100% (90% recommended). So they list four 12 volt batteries to make a 48 volt bank at 130ah. That equals about (48x130) 6240 watt hours. Now divide that 1/2 and that is around the actual usable watt hours, so 3120 watt hours. The spec sheet for the AC unit says it uses about 500 watts per hour under "normal" cooling conditions. So maybe about 5-6 hours of use when there is no sun. They mention that they do not sell these batteries and it's just an estimate, but they carry AGM batteries for sale. So you could supply your own here.

They also note that wires, fuses, shipping, etc are not included in this price. So you're probably realistically looking at around $5000.

I built out my system to run a 12,000 BTU portable AC unit and several other devices. It cost about $5700 and is about 3.5x as large as the one they list, but a lot of the cost is the AC unit in their estimate and mine was only $450. I assume that is a decent AC unit to cost that much.

I don't have experience with DC only AC units, so hard for me to give any advice here. Suggest reading reviews and buy the AC stand alone and build a system around it to save money. Will did a recent series on him running an AC unit in his shed that might help. It's rated at 440 watts, so right around what the one you listed uses. He uses all in one units and that save a lot of money as well, but do have drawbacks (fan noise, high idle consumption).

If you had this solar system, would it be just to run an AC unit or do you have a need for it to run other devices as well? Where is the AC being installed (garage, tiny home, etc.)?

My system as an example:
View attachment 18093

Thank you so much, that was very helpful.

 

[ub2slow2]

It is mostly a marketing thing to make tree hungers feel good. A couple of hundred watts of PV power on even a small 12k BTU unit is not going to contribute very much.

Lenox sells two panels on their 4 ton unit.

Put in a Grid tie system instead. You will have to deal with permitting and approval outside of air cond install.

If you are truely off grid then battery is an option but expensive as the starting current requires a large inverter. There may be some things to help reduce startup current.

ok makes sense and I’ve looked at the ac/dc options also. I am about to pull the trigger on a solar set up for the house and pool house so maybe I can have them help me do this and guide me.

 

[RCinFLA]

Battery capacity looks too small. 120vac 12k air cond is about 10 amps run. Have to know what duty cycle would be at night and day times which depends on area to be covered and its insulation.

With four 12v 100 AH x 80% depth of discharge that is about 4 kWH useable. Without too much other losses that is about 3.5 Hrs run time at 100% duty cycle. Maybe you could make 7-8 hours if duty cycle not too high.

 

[Johnny16]

To the original author of this thread, based on my newly installed system and your requirements, you will need at least 400ah 24v (10kw hour) lead acid battery bank. You can get away with less using lithium batteries.

I have (8) 270w solar panels generating approximately 1,650 watts max from 11am to 5pm. I think i can get away with only 6 pannels because after 1pm, 400watts to 900 watts of my solar energy is dump and not used because the solar charge controller thinks my battery bank is full. I also run a small 6000 btu (450watts) air conditioner for around 2 to 4 hours during the day.

My power usage after dark is around 2,200 watt hour or 90 amp Hour (according to my battery monitor), which is equivalent to running a 500w AC for 4 to 5 hours after solar cut off.

My new lead acid battery bank is 460 Amp Hour or 11kw hour. Regardless of the math. The real life results shows that battery is 24.5v in the morning which is 70% capacity left according to most charts. Based on the battery monitor, power usage is 20% or less, yet my battery bank only have less than 70% charge. From my observation, there is no way to get my Lead Acid Batteries to 100% charge on a daily basis. At the end of the day, my lead acid battery bank is only 90% charged even though solar charge controller show battery voltage as 27.5 to 28.4v for 4 continuous hours before sun goes down.

Right after solar stop charging, my battery bank drops to 25.8 volts which is 100% charged. However, if there is a few minute of 500 watt load, voltage goes to 25.2v (90%) once load is off.

 

[ub2slow2]

Thanks for all the helpful info. I don’t feel like I can really trust their package as advertised. I’m glad I asked for input. I’ll have my solar company help me finalize things for this Air conditioner in DC Mode and build it myself.

 

[Dacrockett001]

I am looking at this 48 volt 12,000 BTU DC air conditioner by Hot Spot Energy. I haven't reached out to them to see what the cost is yet, I am still getting my solar array set up. https://www.hotspotenergy.com/DC-air-conditioner/ I like the idea of not having to use a converter and have so much energy loss.

 

[cwstnsko]

On HotShots complete systems page they list the DC air conditioner as a $1995 item in the parts list

 

[ub2slow2]

I am looking at this 48 volt 12,000 BTU DC air conditioner by Hot Spot Energy. I haven't reached out to them to see what the cost is yet, I am still getting my solar array set up. https://www.hotspotenergy.com/DC-air-conditioner/ I like the idea of not having to use a converter and have so much energy loss.

That’s the same one i was looking at in the package they have for it. My solar guys just said they think they’ve found a cheaper option for me but are still looking and planning it out. I’m trying to keep it totally separate And stand alone from what they are doing for my house. I’m not going with a huge system for the house so I don’t want to steal power from it. It’ll be enough with battery back up to run our well, lights, couple freezers, fridge, water heater and outlets in an off grid situation for long term. I’m also getting a couple of the Yeti solar gens with home integration with battery banks to supplement power in a major power failure that would last months. Fun stuff but not cheap lol

 

[Dacrockett001]

On HotShots complete systems page they list the DC air conditioner as a $1995 item in the parts list

Yes, I thought that one time I had seen the price, but when I was just looking I didn't open the link that had the parts break down. I think 2K for an all DC air conditioner is decent. I live near Las Vegas, where I am setting my solar array I get a good 6+ hours of sun a day.

 

[JoeHam]

And it looks like you have to supply 48 VDC @ 20 amps max to the outside unit.

The inside unit is powered from there.

 

[Dacrockett001]

And it looks like you have to supply 48 VDC @ 20 amps max to the outside unit.

The inside unit is powered from there.

I have four 250 watt 24 volt 8.27 amp panels, I am doing this for my man shed, so mostly I want cooling for the day when the sun is beating on it, and the temperature is 115+ for days on end.