# Solar power update



## Chiefster23 (Feb 5, 2016)

I have posted about my solar setup on here before but I thought an update might be in order.

I have been using my setup to power a small freezer and it works quite well. But on sunny summer days my panels are capable of producing tons of power that I’m not using. I just bought a new window AC unit and I thought I might be able to power it during the day from my panels. I could not run it at night as my battery capacity is not big enough. The AC draws around 600 running watts and I have a Xantrex 2000 watt pure sine wave inverter. Things went well for a short time then the inverter tripped out. It turns out that the cheaper, ‘switching’ type inverters do not handle inductive loads (motors) very well. Motors draw 3 to 5 times as many amps on starting as they consume when running.

So I talked to my supplier and he recommends a transformer type inverter for motor starting loads. These inverters are heavier and of course more expensive. A lot more expensive. Most inverters (both switching and transformer types) advertise that they can handle higher transient starting loads (like those encountered during compressor starting). The devil is in the details. Just how much higher load and for how long is what really makes the difference. Of course higher transient loads for a longer duration means more expensive.

So in order for me to run my AC I’m looking at $1300 to $1700 for a Magnum or Outback inverter. I probably won’t live long enough to get my investment back on this purchase. So I must decide. The ‘return-on-investment’ sucks. But it would be nice to have the capability to furnish a solid 2000 watts of solar power to any appliance in my house. From a prepper standpoint this is a no-brainer. But from a $ standpoint, this requires some thought.

Anyone out there running their AC or water well pump from solar? Got any suggestions or input?


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## sideKahr (Oct 15, 2014)

Always enjoy your posts.

There are 'Soft Start' modules for sale that temporarily reduce the load on AC motors, allowing them to start with inverters that aren't rated for the peaks. I think they're about $300-400. Worth looking into.

https://www.gonewiththewynns.com/product/air-conditioning-off-grid


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## Malcom Renolds (Jul 14, 2017)

Capacitors. Hard start kit. Kinda like a battery JUST for startup.

https://www.amazon.com/Compressor-Saver-Start-Capacitor-Model/dp/B003FNJ37U


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## MountainGirl (Oct 29, 2017)

Chiefster23 said:


> So in order for me to run my AC I'm looking at $1300 to $1700 for a Magnum or Outback inverter. I probably won't live long enough to get my investment back on this purchase. So I must decide. The 'return-on-investment' sucks. But it would be nice to have the capability to furnish a solid 2000 watts of solar power to any appliance in my house. From a prepper standpoint this is a no-brainer. But from a $ standpoint, this requires some thought.
> 
> Anyone out there running their AC or water well pump from solar? Got any suggestions or input?


Mine's a non-technical thought: Life is short, $$ in the bank or stashed wont keep you cool, *and* there may come a time when you want/need the increased ability for other things as well - and wont be able to ramp up then (shtf). Forget return on investment, imo. If you're looking to sell later the bigger system will only up the overall value anyway. My 2-cents.


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## Chiefster23 (Feb 5, 2016)

The soft start ideas are interesting. I will look into that more. It sort of looks like they are not made specifically for window units but I don’t really see why I couldn’t use one in my window AC.

And I tend to agree with Mountaingirl. Having that extra capability would be great. The Outback inverters are very expensive, but they bring a lot to the table. They have an optimizer mode that maximizes the use of the energy from your solar panels and then automatically switches to grid feed when your batteries get low. They also have other modes that can give you lots of flexibility in how you operate your system. I’m pretty sure this brand is top of the line.

I have my kill-a-watt meter in use now to measure how much power the AC unit uses over time. Gotta do a little homework first to determine if this project is even possible with 800 watts of panels.


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## dwight55 (Nov 9, 2012)

Now, . . . first things first, . . . I've not done this.

BUT, . . . I have no doubt it is fully possible.

What you do is bring on the number of inverters you need, . . . for the load you have, . . . in just the same manner all the big power companies do it with their generators.

Also, . . . same way we did it aboard ships in Uncle Sam's Canoe club, . . . with their generators.

Check out some youtube videos on putting them "in parallel", . . . 

They then operate as one big unit.

May God bless,
Dwight


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## Chiefster23 (Feb 5, 2016)

Dwight55. In theory it’s a good idea, BUT! When you add more generators (or inverters) they must be in parallel with each other. The power each generates must be in phase with each other. That’s what a synchroscope is used for aboard ship. So if you want to run inverters (or generators) in parallel, they must be designed for that application. The Honda EU2000 generators can run like that because one genny is the master and the other is slaved to it. The Outback inverters can run like that, too. That’s one reason why they are so expensive.


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## budgetprepp-n (Apr 7, 2013)

You asked about pumping water? Depends if you are not lifting the water very far a R.V. does a nice job.
That's all I have been using for about 2 years and it gets used a lot.


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## Chiefster23 (Feb 5, 2016)

I was referring to an application with a heavy starting load, like lifting water out of a well.

I borrowed a good quality, clamp on amp meter and measured the peak starting amps on my AC, freezer, and fridge. WOW! Those machines all draw about 7 times running amps upon starting. So it is looking like I would need a soft-start kit AND a larger inverter to run my AC. So $300 for a soft-start kit, about $1800 for an Outback inverter, and unfortunately Outback makes you buy an extra device to program and monitor your inverter, another $300. Total $2400! It was a good idea but I don’t think this project is gonna happen.:vs_shocked:


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## Malcom Renolds (Jul 14, 2017)

Chiefster23 said:


> I was referring to an application with a heavy starting load, like lifting water out of a well.
> 
> I borrowed a good quality, clamp on amp meter and measured the peak starting amps on my AC, freezer, and fridge. WOW! Those machines all draw about 7 times running amps upon starting. So it is looking like I would need a soft-start kit AND a larger inverter to run my AC. So $300 for a soft-start kit, about $1800 for an Outback inverter, and unfortunately Outback makes you buy an extra device to program and monitor your inverter, another $300. Total $2400! It was a good idea but I don't think this project is gonna happen.:vs_shocked:


There is a difference between NOT having the money and not wanting to spend the money.
Indoor plumbing, Air Conditioning, Refrigeration, when the rest of the world doesnt have it is PRICELESS. 
At least that is how I "sell" it to Sparkle.

Dont give up on it, You will find a way to "skin that cat" that will work for you.
Some of those things only NEED to start once or twice a day, and you can control when they do that.


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## Chiefster23 (Feb 5, 2016)

I’m still thinking and figuring. LOL. I certainly don’t need an outback inverter. I could go cheaper there. But outback is supposed to be the best, so maybe not a good idea to skimp there. I could probably forgo the meter/controller in the beginning and put that off until later. And there is a ‘chance’ that the inverter may handle the start load without the soft-start kit. I’m going to ponder on it some more. I just thought that some of you solar enthusiasts might enjoy hearing about my schemes and ideas. (My beer keg hot water heater certainly worked out well)

There is no doubt that having this setup would be wonderful when the grid power is out. And I would love to screw the power company on my bill this summer! :vs_smirk:


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## budgetprepp-n (Apr 7, 2013)

Chiefster23 said:


> I was referring to an application with a heavy starting load, like lifting water out of a well.
> 
> I borrowed a good quality, clamp on amp meter and measured the peak starting amps on my AC, freezer, and fridge. WOW! Those machines all draw about 7 times running amps upon starting. So it is looking like I would need a soft-start kit AND a larger inverter to run my AC. So $300 for a soft-start kit, about $1800 for an Outback inverter, and unfortunately Outback makes you buy an extra device to program and monitor your inverter, another $300. Total $2400! It was a good idea but I don't think this project is gonna happen.:vs_shocked:


I only have about 1750 watts of solar panels and I can run my fridge just fine in the summer when we are having sunny days
I just have a 1500 watt pure sine wave inverter $100?


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## Chiefster23 (Feb 5, 2016)

I haven’t actually tried running my fridge on the panels yet, but I expect it will work just fine. I only have 800 watts of solar panels. Today is supposed to be sunny so I think today I will run my heavy duty extension cord and give it a test drive.


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## MountainGirl (Oct 29, 2017)

budgetprepp-n said:


> I only have about 1750 watts of solar panels and I can run my fridge just fine in the summer when we are having sunny days
> I just have a 1500 watt pure sine wave inverter $100?





Chiefster23 said:


> I haven't actually tried running my fridge on the panels yet, but I expect it will work just fine. I only have 800 watts of solar panels. Today is supposed to be sunny so I think today I will run my heavy duty extension cord and give it a test drive.


Hi guys - I might be missing something here... are you talking about solar _directly_ to the fridge?

My system is (simplified) panels > batteries > inverter > appliance. So everything starts & runs off the batts (which provide for the initial amps needed) and the batts are recharged from the panels.

In a few days I'll be installing a solar-direct fan in the new greenhouse (no batts, runs only when sunny-hot) - but the requirement for that little fan is much less than whats needed for a fridge.

What am I not seeing in your setups? Thanks!


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## Chiefster23 (Feb 5, 2016)

You’re not missing anything. I use panels, batteries, and inverter. Nothing is running off 12 volts direct.


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## MountainGirl (Oct 29, 2017)

Ah okay, you're just talking about your input meeting your demand. Cool. Thanks!


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## Malcom Renolds (Jul 14, 2017)

If I may, The issue we are talking about is the "Massive" start up load that occurs on many motors. Many times if a Fridge is rated at 800w and 7amps that is the running stats. That compressor motor will draw 15-20amps for a few seconds on start up, that info is usually on a sticker attached to the compressor and is in LRA or Locked Rotor Amps the draw of the motor when the Compressor is "bad". This extra draw of current has to be accounted for, for the "health" of the Fridge AND the inverters.

Well Pumps, Air Conditioners, and SOME lighting [Ballasted] have the same issue.


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## Chiefster23 (Feb 5, 2016)

Basically I’m just trying to find out what I can run (during daylight hours) from my 800 watts of panels. I have all this equipment and I am definately not using it to its fullest capacity.


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## Chiefster23 (Feb 5, 2016)

Malcom Renolds said:


> If I may, The issue we are talking about is the "Massive" start up load that occurs on many motors. Many times if a Fridge is rated at 800w and 7amps that is the running stats. That compressor motor will draw 15-20amps for a few seconds on start up, that info is usually on a sticker attached to the compressor and is in LRA or Locked Rotor Amps the draw of the motor when the Compressor is "bad". This extra draw of current has to be accounted for, for the "health" of the Fridge AND the inverters.
> 
> Well Pumps, Air Conditioners, and SOME lighting [Ballasted] have the same issue.


Correct. I can run a lot on 800 watts and a 2000 watt inverter. The problems arise upon motor starting. And I can't find any stickers on my appliances that show LRC.


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## hawgrider (Oct 24, 2014)

Chiefster23 said:


> Correct. I can run a lot on 800 watts and a 2000 watt inverter. The problems arise upon motor starting. And I can't find any stickers on my appliances that show LRC.


Electric motors and compressors will require 2.5 times the running amps to start that device.

Example- motor = 14A × 2.50 = 35A.


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## Chiefster23 (Feb 5, 2016)

hawgrider said:


> Electric motors and compressors will require 2.5 times the running amps to start that device.
> 
> Example- motor = 14A × 2.50 = 35A.


Yes, thats what the textbooks say. But I borrowed a very expensive, calibrated amprobe. And this is what I found:
Freezer. 0.9 running amps, 22 peak amps on starting
Fridge. 1.2 amps running. 24.6 peak amps on starting
AC. 6amps running, 44 peak amps starting

Those are amps measured on the "peak" setting on the amprobe. That's a hell-of-a-lot more than 2.5 times running amps. Now I realize that this is just an instantaneous measurement but it seems to be enough to overload the peak amps limit on an inverter and thats the critical factor I'm dealing with. Also, that 2.5 number just deals with the motor. I don't think it takes into account a compressor which may or may not be starting under full load.


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## hawgrider (Oct 24, 2014)

Chiefster23 said:


> Yes, thats what the textbooks say. But I borrowed a very expensive, calibrated amprobe. And this is what I found:
> Freezer. 0.9 running amps, 22 peak amps on starting
> Fridge. 1.2 amps running. 24.6 peak amps on starting
> AC. 6amps running, 44 peak amps starting
> ...


Its a general rule of thumb.

Other conditions may apply. Like a fridge or freezer that has seen better days will take more to start and get off the start windings.
if the equipment is old then the general rule of thumb may not apply. And thats what they make amprobes for. If in doubt then check it out.


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## MikeTango (Apr 13, 2018)

Chiefster23 said:


> Yes, thats what the textbooks say. But I borrowed a very expensive, calibrated amprobe. And this is what I found:
> Freezer. 0.9 running amps, 22 peak amps on starting
> Fridge. 1.2 amps running. 24.6 peak amps on starting
> AC. 6amps running, 44 peak amps starting
> ...


Let's take the 24.6 amp peak you tested on the fridge. I'd be willing to bet when it's plugged into the wall it's on a circuit with a 20amp breaker. Mine is, I just checked.

How is it the breaker doesn't fault every time the fridge starts?

I have a small inverter type gas powered generator rated at 2000 watts/16.7amps start up and 1600watts/13.3amps continuous running output.

It runs the fridge just fine and has never popped the breaker.

The fridge was manufactured November 2015 and the motor draws 6.0 amps according to the sticker inside the fridge.

I don't have access to a tester to see what the actual numbers look like on my fridge.

Would there be any difference between the inverter on my generator and the inverter you're using with batteries?

Something else I heard but haven't researched is newer electric motors in appliances operate with several stages to reduce the initial amp draw at startup.

How old is the fridge you're using?

Just throwing all this out there in hopes it helps somehow...

Sent from my iPhone using Tapatalk Pro


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## Chiefster23 (Feb 5, 2016)

The peak amps measured is an instantaneous load and only lasts for a few milliseconds. Certainly not long enough to trip any household circuit breaker. And my fridge isn’t tripping my inverter because I haven’t tried running my fridge on my solar system yet. I only gave those numbers to illustrate the peak starting load vs the running loads. I’m interested in running my AC on the inverter. I also have a 2000 watt inverter type generator that runs my fridge just fine.


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## MikeTango (Apr 13, 2018)

Chiefster23 said:


> The peak amps measured is an instantaneous load and only lasts for a few milliseconds. Certainly not long enough to trip any household circuit breaker. And my fridge isn't tripping my inverter because I haven't tried running my fridge on my solar system yet. I only gave those numbers to illustrate the peak starting load vs the running loads. I'm interested in running my AC on the inverter. I also have a 2000 watt inverter type generator that runs my fridge just fine.


I'm curious if you've tried to run your new AC unit off your 2000 watt inverter type generator? Just to see if it can handle the peak starting load.

Another thought; maybe you could find a used inverter type generator for sale that you could purchase for cheap and use the inverter out of it. I was thinking a 5000 watt model from a construction outfit or something. The engine may be shot but the inverter portion completely usable.

Sent from my iPad using Tapatalk Pro


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## MikeTango (Apr 13, 2018)

Obviously, I’m new to solar and have no experience what so ever. Eventually I’d like to learn enough to be able to build and implement a small system. I’m just throwing stuff out there in hope it helps...


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## budgetprepp-n (Apr 7, 2013)

Here's what I know for a fact,, I have a 1500 watt inverter and has a peremptory surge 
that's higher than 1500 (not sure what it is) and it runs my refrigerator ,TV, computer
and some small appliances just fine. And my fridge is not a tiny one.


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## Chiefster23 (Feb 5, 2016)

Yesterday was sunny here, so I hooked up my fridge to my existing 2000 watt inverter. It ran fine. I’m busy this weekend but next up I’m going to try running both my fridge and freezer at the same time. I suspect it will work, except if both try to start at the exact same time. We’ll see.


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## Chiefster23 (Feb 5, 2016)

Update! After some research I ordered an OUTBACK inverter. It is expensive but it has one feature that just exactly fits my plans. I can supply inputs into the inverter from both my batteries and the grid. Then I program the inverter to maximize the use of solar power until my batteries discharge to a certain setpoint (that I determine) then it will seamlessly switch the loads to grid power. As a bonus I’m pretty sure that this inverter will also power my AC unit. 

Since my battery bank is somewhat limited, I am frequently checking the state-of-charge. This new inverter should eliminate my worries as it will auto transfer to grid power when the batteries run down to a certain setpoint. I will probably set it to allow the batteries to discharge about 20%. After the new toy is up and running I will post my results and impressions.


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## soyer38301 (Jul 27, 2017)

Very nice...batteries are always my biggest worries. My first wind gen setup I had to check them several times a day. 
I am also looking at a solar setup for the new house that has Outback parts 8n the guts of it. I will be interested in any updates you post 
Thanks.

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## 0rocky (Jan 7, 2018)

Chiefster23 said:


> I have all this equipment and I am definately not using it to its fullest capacity.
> 
> Update! I can supply inputs into the inverter from both my batteries and the grid.


Just a thought but since you mentioned you are on the grid and you are under utilizing your solar cell power output; have you given any thought to hooking up a grid tie inverter and lowering your electric bill and recouping your equipment costs?


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## Chiefster23 (Feb 5, 2016)

I only have 800 watts of panels. And grid-tie involves additional expense. Plus the electric company doesn’t want to pay you squat for your power.


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## soyer38301 (Jul 27, 2017)

Chiefster23 said:


> I only have 800 watts of panels. And grid-tie involves additional expense. Plus the electric company doesn't want to pay you squat for your power.


Hardly worth it most of the time

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