Powering a mini split

[Screwball]

My setup is fairly similar: 26 x 102 ctc with 2000w pv and most likely 24v 408ah lifepo4 ... 9000btu senville inverter heat pump split.
My goal is to run the split off of solar here in the west ... at least during sunny hot days (thankfully there is usually not much need for nighttime ac in the desert)
However, a Honda 2000i going thru the victron multiplus inverter is the backup plan ?

 

[iamrich]

I literally have no idea what inverter to use. But I do like the 6x350w style panels! And all I have on the roof is a standard vent. Nothing else.

Tough call because you can get the 250w panels (8) for half the price (maybe less), but that extra 100w is forever (or 25 years I guess ).

 

[Screwball]

Tough call because you can get the 250w panels (8) for half the price (maybe less), but that extra 100w is forever (or 25 years I guess ).

Just as a FYI for op in case your searching: just stumbled over these new 350w half cell REC locally ...

 

[chrisski]

Until you run the AC for 24 hours under different outside temp conditions.

I don’t buy that. There’s got to be a reasonable way to calculate this without doing government math of floating multiple credit cards until you’ve bought enough panels, SCC and wiring to run your A/Cs.

This is a little more than a backyard project you run back and forth to Home Depot for a few times to get a few screws and then return for washers, etc; this is a project that you could spend $10k on up to $25k to build a system from ground up.

There’s a way to reasonably estimate how much power your A/C requires. Probably a math formula involving BTU’s, seer rating, square feet.

 

[Bob B]

Maybe you can contact someone who has done it successfully .... someone like this guy.

 

[corporate.joe]

This couple shows the wattage while in using this mini-split. Read from their Victron system.

 

[Brasher801]

If money its not much of a problem, consider checking on higher SEER units.

For example, a 12K BTU inverter with 16 Seer would take around .75Kwh, for 8 hours, that's almost 6Kwh, so in my case 3 or 4 400W panels could make it.

There is 30 Seer inverters, so 3.2Kwh for the same 8 hours, almost half of energy and panels!, but around 500 - 800USD extra or more depending of the size.

Disclaimer: Maybe im wrong since i havent done this numbers in a while.

I believe the pioneer I bought is a 20 seer.

 

[Brasher801]

Maybe you can contact someone who has done it successfully .... someone like this guy.

Man!! This guy is a McGyver for sure!

 

[Brasher801]

This couple shows the wattage while in using this mini-split. Read from their Victron system.

Interesting Video. Pretty cool looking install also.

 

[RogerD]

Maybe you can contact someone who has done it successfully .... someone like this guy.

Nope, he will tell you there are too many variables. I contacted him when he first put that video out.

 

[Brasher801]

I have 8’ x 24’ I can use

Has anyone put a rack on top of a Cargo Trailer? I can't find any videos of it if they have. Mine has a flat roof.

 

[RogerD]

I don’t buy that. There’s got to be a reasonable way to calculate this without doing government math of floating multiple credit cards until you’ve bought enough panels, SCC and wiring to run your A/Cs.

This is a little more than a backyard project you run back and forth to Home Depot for a few times to get a few screws and then return for washers, etc; this is a project that you could spend $10k on up to $25k to build a system from ground up.

There’s a way to reasonably estimate how much power your A/C requires. Probably a math formula involving BTU’s, seer rating, square feet.

Outside temp and how well your rig is insulated needs to be added.

 

[Screwball]

Has anyone put a rack on top of a Cargo Trailer? I can't find any videos of it if they have. Mine has a flat roof.

I did twin 21' unistruts on custom Z's bolted to each roof bow... was painful to drill the seamless roof, but I rather be safe then sorry
Plus the panels shed almost all rainwater anyway, so im not concerned with leaks.

Running 8 x 250w for now ... thinking to may upgrade to 6 x 400w later down the road (nice thing on unistrut tracks is that your flexible for changes ?)

 

[iamrich]

So based off the video on page 2 it looks like they where pulling 500watts per hour for the most part. That's 12kwh per day, so with 2kw of panels and 5 hours of sun, you are still going to come up ~2kwh short everyday (and that assumes you use nothing else). So you either need to use the AC less than 24 hours, add more solar, or supplement with a generator. Based off the dimensions you might be able to squeeze 7 400w panels, but then you are stuck with running them all in parallel and that would be a big ass wire from the combiner box to the inverter. I think that would put you at ~42v and ~70a and you would have seven sets of wires on the roof.

 

[Brasher801]

So based off the video on page 2 it looks like they where pulling 500watts per hour for the most part. That's 12kwh per day, so with 2kw of panels and 5 hours of sun, you are still going to come up ~2kwh short everyday (and that assumes you use nothing else). So you either need to use the AC less than 24 hours, add more solar, or supplement with a generator. Based off the dimensions you might be able to squeeze 7 400w panels, but then you are stuck with running them all in parallel and that would be a big ass wire from the combiner box to the inverter. I think that would put you at ~42v and ~70a and you would have seven sets of wires on the

Holy Cow!! I think, realistically, that I will need the AC during the day and maybe a few hours at night. I will be chasing nice weather most of the time. But you can't always have nice weather!!!

 

[NMNeil]

I still think by now, someone has some data that can be used to really plan how much energy is used such as, "During the Maine summer day of 85° I used XXX watts per hour, to maintain a temp of 76°" or in my case, "On a hot summer night in Arizona of 91°, I used XXX watts per hour to maintain a temp of 80°." A couple of examples about the extremes in your area, in my case one for day and one for night, would narrow this down.

We can all read the start up amps, and figure out watt hours from there by guessing, but there has got to be a better way than, "You've got to build it to find out." After all, this is not Congress. I can't afford to buy into the idea of Air Conditioning without knowing what its going to cost, because unlike the federal government, I have to pay my bills.

There is no standard answer, sort of like how long is a piece of string?
If you're single, your power consumption may be low, if married, it will be a lot higher, as the temperature will never be quite right.
If your house is super insulated power consumption will be low, if the house leaks like a sieve, it's going to be higher.
Then there's simple economics. Over the years I've spent thousands on my solar system, so to save the $15 or so a month I paid to power my old central air would take decades to recoup.

 

[iamrich]

Holy Cow!! I think, realistically, that I will need the AC during the day and maybe a few hours at night. I will be chasing nice weather most of the time. But you can't always have nice weather!!!

I think it will be doable honestly. I think if you run a 2000w panel system, 400ah of 24v lifepo, and a decent all in one inverter you will have enough power. As long as you are conscious about your power use and don't sit in the trailer 24/7 your power usage is going to be lower. Turn the temp up to 80F if you are not in the trailer, make sure all the lights and anything unneeded are turn off. Lastly have that 2000w (or similar) generator stored for emergencies. You can run a quiet generator even in a camp ground from dusk to bedtime and that will both power your AC and charge your batteries to get you through the rest of the night. And if the camp ground has power available, even better.

 

[Freep]

I did twin 21' unistruts on custom Z's bolted to each roof bow... was painful to drill the seamless roof, but I rather be safe then sorry

Really? I'd rather not be sorry at all.

 

[Hendo7]

my opinion is you should of got a 110v mini that's 9k BTUs ,this way you are tunning all the power through one leg of 110v not two.
i run 1500 watts of solar through 4 x40 amp charge controllers and about 200ah of batteries,its able to run about 4 hrs into the night on hot days 100+
though i do wish i got a inverter mini split with a seer value more than 18,those things are amazing and use about half the power of a standard mini split.
in addition to the info above while i am running the ac in hot days i am still charging my batteries and half of my battery bank is golf cart sla which will be replaced with the 271,s once they get here

 

[Uoavitar]

There is no standard answer, sort of like how long is a piece of string?

Twice the distance from the center to either side.