About to spend $ on EG4-6000XP - sanity check?

[azscooby]

I’m a newbie to solar, but not to DIY. I expect to be able to self install this entire setup, I’ve got the tools and skills (mostly.). I’ve spent the last two weeks watching all of Wills videos as well as dozens of others. I’ve got most of the basics.

Some background - I live in the Phoenix metro area. Home built in 1979 that’s fairly well insulated, 2000 sq ft, radiant barrier, attic fan with 4ton American Standard two stage heat pump. My equalizer SRP (local utility company) would be $250, winter this year averaged around $100 while summer is $250-$335. I’m a single dad who has my kids half of the time (14 and 11). When they’re not here I spend probably 90% of the day in one room and the nights in the MBR. I’m paying a lot to cool a home that’s mostly empty.

My goal is to become somewhat independent from grid power (for the inevitable zombie apocalypse of course) and to increase comfort (cooling) during summer without having to scream at the kids to close the door (I think every generation gets that, lol.) . I do not plan to be grid free, not for some time at least. I understand this project likely won’t save me any money for a decade or so. I’m not here for ROI. That’s fine. I understand what I’m paying for but I would like to maximize my purchases and setup for that end goal. Nothing is getting cheaper and I’m an idiot for waiting…..but here we go.

What I’d like to do is put 12k mini splits in the 3 rooms where we spend our time. Ideally the main 4ton unit would be cranked up to 85/90 during the day and then back on after 8PM (time of use plan.). When I’m home alone, I could very comfortably live with just two rooms being cooled (2x 12kton minis).

I did end up buying an Airspool 12k Hybrid unit for the family room (400 sq ft), more as a “get my feet wet” and now I’m hooked and see the potential solar seems to have finally cracked the AC issue. It’s up and running on 5 x 400 watt Alexus panels and I’m freezing, it’s great so far.

But after reading here and doing the math, I’m much better off buying an inverter, a few batteries, and panels but then using regular non hybrid minisplits for each room remaining. Those units can be had for as little as $400-$700 vs the $2k for the EG4 and Airspool Hybrids.,..that’s a huge difference. A difference that another poster pointed out would be much better spent on inverter, batteries and panels as the extra solar could be used to run other circuits when not being sent to the minisplits. Plus I could use batteries until they ran out.

So, my preliminary shopping list looks like this.
EG4-6000XP (got quote from Santan solar for $1529 OTD, local pickup). better deals elsewhere?
Minimum 200AH batteries according to what I can find (need help on this)
Solar panels to run it all (local to Santan so should be able to find good deals)
Wiring/boxes, etc
3 x 12k ton minisplits (non hybrids to run from inverter)

Assuming I have the correct number of panels, wiring, tools, batteries etc, am I missing any major components? The EG4-6000xp has the MPPT and SCC all in one, right?

I want to make sure I understand how the 6000XP works. The 6000xp will accept grid power input, I know that, but, does this mean that once my batteries are depleted (at min SOC) it will power whatever I have on it from the grid?

So if I have a mini split or two plugged into the inverter (6000xp) I should be able to run whatever I have plugged into (assuming I’m not over max withdrawal) from solar during day, then to batteries and then to grid? Meaning, the minisplits should be able to run 24/7 if I’ve set it up properly? This is my biggest concern/question.

As far as the batteries, what does 200AH of batteries look like price wise ( cheap wise)? And what voltage should those batteries be? Guessing 48 volt? Do the cheaper Amazon LiFePO4 batteries fit that bill? How many would I need as a minimum to get started? Cost? This is the one unknown cost I haven’t accounted for yet. I understand I can add them as I go, so I just want the minimum (or minimum recommended) to get me started,

Am I missing anything? Am I on the right path? I want to avoid nickel and diming it as these projects often go.

Wanted to thank a fellow local here on the forum who’s been especially helpful via DM. He’s the one who made me realize the hybrids aren’t necessarily the best way to go. (Smith AZ or something like that.)

 

[Rocksnsalt]

I’m no expert but 200ah of 48v or 10.24kwh of batteries seems a bit light for running ac and other loads in the Phoenix area. Though the mini splits are certainly more efficient.
Will it help, heck yeah, sure.

Have you figured out projected
1) Average daily kw use
2) Average daily of solar kw input
3) Night kw use?
I’d be looking at something more like 2 of the EG4 Wall mount 14.8kwh batteries or similar.
So you can crank temps down nice and chilly to combat those 117F and humid august or “monsoon season” temps
Or 1 battery to start, but shipping costs…

With Phoenix heat, I would assume that batteries will live in an at least somewhat cooled space?

The the 6000xp is an off grid all in one

EG4 6000XP Off-Grid Inverter | 8000W PV Input | 6000W Output | 480V VOC Input | 48V 120/240V Split Phase | All-In-One Solar Inverter

EG4 6000XP Off-Grid Inverter: 6000W output, 8000W PV input, 480V VOC, and 48V split-phase 120/240V. Efficient power for off-grid setups. Available now at Signature Solar.

signaturesolar.com

And

Re “3 x 12k ton minisplits (non hybrids to run from inverter)”
This should be written as 12kbtu (or 1 ton)

 

[chrisski]

I don’t have good data yet for my mini-split in phoenix, but I expect each unit to pull 20 kWh per room per day in the summer.

I can tell you that from April 6 - 30, I pulled 100 kWh for a two car garage set to 80 degrees. That’s about 5 kWh per day for a month that mostly saw below 80 degrees.

 

[Rocksnsalt]

Yikes.
What size mini splits and how’s your insulation, glass area, and any shade on the house?

 

[HarryN]

Rough energy budget numbers, each of the mini-splits will use ~ 1 kW average to keep 1 - 2 rooms cool, assuming that the rest of the house is warm but not hot.

( 200 amp-hrs ) x ( 50 volts ) ~ 8 kW-hrs, so that is ~ 8 hrs run time for one unit assuming that the batteries are full when you start.

Using solar to power to generate power all day long will take ~ 1.5 kW of panels facing the sun all day long, so nominally 1.5 kW facing each direction morning, mid day and late afternoon.

The most expensive power is in the late afternoon, so you could start there and mount panels to face the sun starting around 2 or 3 in the afternoon until the sun goes down as a starting point.

Perhaps charge up the batteries from the grid overnight when rates are lower.

 

[chamilun]

current connected may have it cheaper. Id reach out to eg4 and see if they would pricematch.

 

[fmeili1]

So if I have a mini split or two plugged into the inverter (6000xp) I should be able to run whatever I have plugged into (assuming I’m not over max withdrawal) from solar during day, then to batteries and then to grid? Meaning, the minisplits should be able to run 24/7 if I’ve set it up properly? This is my biggest concern/question.

Yes, that's correct.
Depending on the setting, the inverter uses PV/battery until the SOC (or voltage) of the battery reaches a low trigger value which closes the internal grid bypass relay and the connected loads will be driven by the grid.
Depending on the grid charge settings in the inverter, the battery may be recharged from the grid in parallel while grid is used to drive the load - but this is optional. If the batteries reach a trigger SOC (or voltage) configured in the settings (recharged by PV or grid) the bypass relay will switch off and the inverter will drive the load again from PV/battery.

 

[1201]

I’m a newbie to solar, but not to DIY. I expect to be able to self install this entire setup, I’ve got the tools and skills (mostly.). I’ve spent the last two weeks watching all of Wills videos as well as dozens of others. I’ve got most of the basics.

Some background - I live in the Phoenix metro area. Home built in 1979 that’s fairly well insulated, 2000 sq ft, radiant barrier, attic fan with 4ton American Standard two stage heat pump. My equalizer SRP (local utility company) would be $250, winter this year averaged around $100 while summer is $250-$335. I’m a single dad who has my kids half of the time (14 and 11). When they’re not here I spend probably 90% of the day in one room and the nights in the MBR. I’m paying a lot to cool a home that’s mostly empty.

My goal is to become somewhat independent from grid power (for the inevitable zombie apocalypse of course) and to increase comfort (cooling) during summer without having to scream at the kids to close the door (I think every generation gets that, lol.) . I do not plan to be grid free, not for some time at least. I understand this project likely won’t save me any money for a decade or so. I’m not here for ROI. That’s fine. I understand what I’m paying for but I would like to maximize my purchases and setup for that end goal. Nothing is getting cheaper and I’m an idiot for waiting…..but here we go.

What I’d like to do is put 12k mini splits in the 3 rooms where we spend our time. Ideally the main 4ton unit would be cranked up to 85/90 during the day and then back on after 8PM (time of use plan.). When I’m home alone, I could very comfortably live with just two rooms being cooled (2x 12kton minis).

I did end up buying an Airspool 12k Hybrid unit for the family room (400 sq ft), more as a “get my feet wet” and now I’m hooked and see the potential solar seems to have finally cracked the AC issue. It’s up and running on 5 x 400 watt Alexus panels and I’m freezing, it’s great so far.

But after reading here and doing the math, I’m much better off buying an inverter, a few batteries, and panels but then using regular non hybrid minisplits for each room remaining. Those units can be had for as little as $400-$700 vs the $2k for the EG4 and Airspool Hybrids.,..that’s a huge difference. A difference that another poster pointed out would be much better spent on inverter, batteries and panels as the extra solar could be used to run other circuits when not being sent to the minisplits. Plus I could use batteries until they ran out.

So, my preliminary shopping list looks like this.
EG4-6000XP (got quote from Santan solar for $1529 OTD, local pickup). better deals elsewhere?
Minimum 200AH batteries according to what I can find (need help on this)
Solar panels to run it all (local to Santan so should be able to find good deals)
Wiring/boxes, etc
3 x 12k ton minisplits (non hybrids to run from inverter)

Assuming I have the correct number of panels, wiring, tools, batteries etc, am I missing any major components? The EG4-6000xp has the MPPT and SCC all in one, right?

I want to make sure I understand how the 6000XP works. The 6000xp will accept grid power input, I know that, but, does this mean that once my batteries are depleted (at min SOC) it will power whatever I have on it from the grid?

So if I have a mini split or two plugged into the inverter (6000xp) I should be able to run whatever I have plugged into (assuming I’m not over max withdrawal) from solar during day, then to batteries and then to grid? Meaning, the minisplits should be able to run 24/7 if I’ve set it up properly? This is my biggest concern/question.

As far as the batteries, what does 200AH of batteries look like price wise ( cheap wise)? And what voltage should those batteries be? Guessing 48 volt? Do the cheaper Amazon LiFePO4 batteries fit that bill? How many would I need as a minimum to get started? Cost? This is the one unknown cost I haven’t accounted for yet. I understand I can add them as I go, so I just want the minimum (or minimum recommended) to get me started,

Am I missing anything? Am I on the right path? I want to avoid nickel and diming it as these projects often go.

Wanted to thank a fellow local here on the forum who’s been especially helpful via DM. He’s the one who made me realize the hybrids aren’t necessarily the best way to go. (Smith AZ or something like that.)

I really think you'll be better off with a hybrid inverter like the growatt sph10k hu us and an interconnection agreement. It would be a simple agreement if there is no rooftop PV in the plan(you can add that later)

The hybrid can support ALL your loads, not just the mini splits. Even your 4 ton.

Also, surges are not a thing with a hybrid since the grid handles the surges.

Finally it's not switching back and forth between inverter and grid. They are both connected all the time.

 

[azscooby]

I’m no expert but 200ah of 48v or 10.24kwh of batteries seems a bit light for running ac and other loads in the Phoenix area. Though the mini splits are certainly more efficient.
Will it help, heck yeah, sure.

Have you figured out projected
1) Average daily kw use
2) Average daily of solar kw input
3) Night kw use?
I’d be looking at something more like 2 of the EG4 Wall mount 14.8kwh batteries or similar.
So you can crank temps down nice and chilly to combat those 117F and humid august or “monsoon season” temps
Or 1 battery to start, but shipping costs…

With Phoenix heat, I would assume that batteries will live in an at least somewhat cooled space?

The the 6000xp is an off grid all in one

EG4 6000XP Off-Grid Inverter | 8000W PV Input | 6000W Output | 480V VOC Input | 48V 120/240V Split Phase | All-In-One Solar Inverter

EG4 6000XP Off-Grid Inverter: 6000W output, 8000W PV input, 480V VOC, and 48V split-phase 120/240V. Efficient power for off-grid setups. Available now at Signature Solar.

signaturesolar.com

And

Re “3 x 12k ton minisplits (non hybrids to run from inverter)”
This should be written as 12kbtu (or 1 ton)

Thanks for the reply!

To clarify - I don't plant to go off grid, entirely. Only to run specific loads during my peak production (running mini split full tilt while solar is maxed and then using what little battery will produce and then finally back to grid.) I don't think it's even $ reasonable given power is relatively cheap in PHX. In the winter, without any HVAC needed, my bill rarely exceeds $100. Granted winter rates are a bit lower. But for the months of June, July, August, September and NOW October (last year half of october was 110+)

SRP does not seem to encourage solar, they seem openly hostile to be honest (but I've recently learned alot and understandy why), so I do not want to deal with a grid tie to backfeed to the grid.

I do want an inverter unit that will allow me to fallback on grid power, which is my main question with the EG4-6000xp - I think that's been answered.

Yes - batteries will live inside a room I have planned that will be cooled. I actually install remote systems for data collections (AZ Water resources) using solar/battery setups and we understand very well how long batteries last in AZ heat....so for sure will be keeping them cool.

I don't plan to run the minisplits from battery for any real amount of time, at least at the beginning. This is why I wanted to make sure that the priority for draw from the inverter could be programmed such that it would draw from PV first, then to batteries, then to grid without having to manually switch anything. Ideally, the batteries would last at least until 8PM when energy costs go down quite a bit.

I understand batteries seem to be the biggest expense and are an ongoing expense given their lifespan.

"Re “3 x 12k ton minisplits (non hybrids to run from inverter)”
This should be written as 12kbtu (or 1 ton)" - Yeah - my bad. I knew that, just way too many numbers and new acronyms for me to

 

[chrisski]

Yikes.
What size mini splits and how’s your insulation, glass area, and any shade on the house?

For me, the insulation is non existent, in the wall and Maybe 24 SqFt of glass. The garage door is uninsulated and plenty to leak out.

The AC is to keep the batteries cool.

 

[Adam De Lay]

So, my preliminary shopping list looks like this.
EG4-6000XP (got quote from Santan solar for $1529 OTD, local pickup). better deals elsewhere?

Current Connected has them for $1,411.99 if you create a website account plus free shipping on them for the month of May.

 

[azscooby]

I don’t have good data yet for my mini-split in phoenix, but I expect each unit to pull 20 kWh per room per day in the summer.

I can tell you that from April 6 - 30, I pulled 100 kWh for a two car garage set to 80 degrees. That’s about 5 kWh per day for a month that mostly saw below 80 degrees.

Good to know.
I don't expect to be able to cool the entire 2000 sq ft entirely, at least initially, from solar and batteries alone. I think I'm being realistic in what I expect.

For fun - here's my SRP usage for the past 30 days or so. The 4 Ton heat pump is barely running these days.

Can you guess which days I have the kids? Most of their usage is those GAMING PCS! I'm actually shocked to see how much

Yes, that's correct.
Depending on the setting, the inverter uses PV/battery until the SOC (or voltage) of the battery reaches a low trigger value which closes the internal grid bypass relay and the connected loads will be driven by the grid.
Depending on the grid charge settings in the inverter, the battery may be recharged from the grid in parallel while grid is used to drive the load - but this is optional. If the batteries reach a trigger SOC (or voltage) configured in the settings (recharged by PV or grid) the bypass relay will switch off and the inverter will drive the load again from PV/battery.

Great! This is what I’ve been trying to find out!

So ideally, I want to have enough panels to drive 3-4 12k btu minisplits during the day, then switch to battery which ideally would run until 8PM when my “time of use” rates get cheaper. I understand that amount of batteries may be cost prohibitive (for me.)

Can someone give me an idea of what the minimum battery requirements look like? Like literally what batteries do I need (how many, what voltage, amp hours, etc.?). I know the manuals says 200Ah but I didn’t look at what volatile.

So, will the cheap Amazon LiFePo4 batteries for $150 work? And how many of them?

Thanks again

 

[azscooby]

Current Connected has them for $1,411.99 if you create a website account plus free shipping on them for the month of May.

I will check them out! That’s a lot cheaper than Santan and they have to order them.

 

[chrisski]

So ideally, I want to have enough panels to drive 3-4 12k btu minisplits during the day, then switch to battery which ideally would run until 8PM when my “time of use” rates get cheaper. I understand that amount of batteries may be cost prohibitive (for me.)

What is your budget?

To run this overnight on power will be pricey. It’s likely each mini split will require 10 kWh of batteries to run overnight in the summer months when AC runs 24/7. This isn’t Maine, AC needs to run 24/7 for 6 months a year.

A battery installed for that will run you $12k installed to cover the power required to run a single AC overnight.

That $12k per battery includes permitting and inspection and a decent safe install. That’s about the market rate to have a Tesla powerwall installed.

I’m guessing if you know what you’re doing, $6k will get you the battery, parts and tools for the install for DIY. I doubt an individual in the city could easily do a DIY permitted build.

I think with panels and all, you’re looking at $50 k DIY or $100 k installed for you. This would cover your ACs with battery power.

Probably much cheaper to pay for electricity than go completely off grid for those ACs.

 

[azscooby]

I don’t have good data yet for my mini-split in phoenix, but I expect each unit to pull 20 kWh per room per day in the summer.

I can tell you that from April 6 - 30, I pulled 100 kWh for a two car garage set to 80 degrees. That’s about 5 kWh per day for a month that mostly saw below 80 degrees.

Good to know.
I don't expect to be able to cool the entire 2000 sq ft entirely, at least initially, from solar and batteries alone. I think I'm being realistic in what I expect.

For fun - here's my SRP usage for the past 30 days or so. The 4 Ton heat pump is barely running these days.

Can you guess which days I have the kids? Most of their usage is those GAMING PCS! I'm actually shocked to see how much

 

[chrisski]

I don’t see any statement.

Good to know.
I don't expect to be able to cool the entire 2000 sq ft entirely, at least initially, from solar and batteries alone. I think I'm being realistic in what I expect.

For fun - here's my SRP usage for the past 30 days or so. The 4 Ton heat pump is barely running these days.

Can you guess which days I have the kids? Most of their usage is those GAMING PCS! I'm actually shocked to see how much

With out running “off grid,” Will be much cheaper.

Once you figure out your kilowatt and kilowatt hour requirement, you can figure exactly what you need.

My guide for prices of an installed system, fairly accurate for the Phoenix Area:

1) Batteries $1k per kWh.
2) Solar Panels $3 per Watt.

10 kW of panels and a 10 kWh battery will really cut into your bill. Not like your neighbors who had it for years tell you they have no bill, they have a NEM1 type good deal contract with the Power Company, the new obene is a NEM3 POCO friendly contract.

The bare minimum 10 kWh battery is the smallest you want installed for a hybrid, DC coupled system. For me, 10 kW of Panels made 30 kWh a Day in the shortest days of the year and 60 kWh in the longest day of the year. Compare that to your actual usage from your bill. Just choose an extreme month like July and extreme on the other end like December, and figure how much that cuts into your daily usage.

Also keep in mind you only have about 5 kWh of useable battery pack going into the night, so most of the savings will go into the day. Maybe about 70% of what any easy math tells you what to save.

My guess is your winter bills with gas heat and cooking will drop to about $20 to $40 per month, and your summer bills will drop to about $100-$150. I’m assuming your winter bill is around $75 per month and the summer bill is $330 per month.

 

[ksmithaz1]

Just to be clear, by "During the day" in Phoenix we would be talking until TOU ends at 20:00, so about 5 hours after solar output starts it's steep decline, depending on panel placement. My first setup had 30KWH of battery, which always lasted until 10PM, with the 4T running wide open. From a major cost savings standpoint you are looking at window from 15:00-20:00, so even if the batteries don't make it past 18:00-19:00 your savings are significant. ROI is another matter. Just buying splits, and letting the rest of the house roast while holing up the the cold room would save the most money.