What would you do?

[johnim]

I have one EG4 standard server rack 48V batt paired with the EG4 3000W inverter for my skoolie build and with 2 110V 12k mini splits I'm already seeing this set up will not be enough without significant power restraints when both minisplits are running or add another inverter/battery.

The mini itself runs about 1.2kw on the highest cool setting and less than half that typically. And that's fine if fully charged but as I'm seeing today when I'm waiting to recharge depleted batteries and it's an overcast day it's a long hot wait. So yea I need backup more than total power but I need more total power too.

Would you spend another $749 on another 3000W inverter and run it in parallel or get the 6.5kw big brother and maybe sell the 3000W inverter?

 

[rmaddy]

It sounds like you need more battery and solar, not more inverter.

 

[johnim]

solar is maxed out at 2880W on top of the skoolie with no extra room...battery I already mentioned

 

[rmaddy]

Can you explain what you think you will get out of adding another inverter? It sounds like your current inverter is fine since it can run your loads. You just don't have enough battery capacity on cloudy days. So adding more battery will give you more time. But without more solar you might not be able to recharge the increased battery capacity.

 

[GLC]

I have 14,400 watt hours of battery storage (12 Battleborn Batteries), 2/4000 watt inverters, 4100 watts of panels. I have two mini splits, No way will mine keep with that load and 90 percent of my 110 circuits. Just the mini splits use about 1200 watts in an hour x 2=2400 watts. Minus the hours that the sun is giving me PV which is about 7 hours, that means I need enough storage for 40,800 watt hours or 34 / 12 volt 100 AH batteries in a 24 hour period. Best be adding a lot of battery storage if you are planning to rely on solar 24 /7. Then if you have 40,800 watt hours of storage and are planning to charge them with PV and run your units while the sun is shining, then you will need 200 / 300 watt panels to charge the batteries and power the unit while the sun is shining. This is a tall order.

 

[johnim]

how in the heck would you need 40,000 watts per day when the average American household uses around 15kw per day if memory serves. remember the minis will be around 1.2kw load for about two hrs worst case scenario because we are talking a 95 degree bus but once it cools down a bit less than half that...maybe 600 max. for my solar system best case scenario is about 15kw generated per day...that's 2880W x6 hr at about 85% efficiency but it's better than that. in any event a working plan for 15kw/day is very attainable. so yea battery may be the biggest consideration right now but back to the 3000 watt inverter if there's a 2.4kw load just from the minis it doesn't give me as much wiggle room as I would like so a larger inverter has to be considered.

 

[rmaddy]

but back to the 3000 watt inverter if there's a 2.4kw load just from the minis it doesn't give me as much wiggle room as I would like so a larger inverter has to be considered.

OK, that answers my question. You have more than 3kW of loads you want to run at the same time.

Considering your current system can't handle 2.4kW of loads from the two mini splits, it seems odd to be asking about adding a bigger inverter so you can run even more loads.

To run more loads you need more battery and more solar. But it seems you can't add more solar as you state the roof is full. You could supplement with some ground mount panels you can put out when needed. Of course you need a place to store them when not in use. You add a separate solar charge controller just for the ground mount panels.

Once you have more solar and more battery that easily supports your 2.4kW loads then you would be in a position to consider supporting more loads with a bigger inverter.

Of course an alternative to adding more loads is to find a way to use less loads. Maybe turn off one mini split to run a microwave or whatever your extra AC loads are. Propane is the way to go for cooking and hot water. It's a matter of priorities and what you have to work with.

Just the mini splits use about 1200 watts in an hour watts x 2=2400 watts

Minor correction of units. The mini split uses about 1200 watts. In an hour it would use 1200 watt hours. In 17 hours your two mini splits use 40.8kWh (40,800 watt hours).

 

[JRH]

how in the heck would you need 40,000 watts per day when the average American household uses around 15kw per day if memory serves. remember the minis will be around 1.2kw load for about two hrs worst case scenario because we are talking a 95 degree bus but once it cools down a bit less than half that...maybe 600 max. for my solar system best case scenario is about 15kw generated per day...that's 2880W x6 hr at about 85% efficiency but it's better than that. in any event a working plan for 15kw/day is very attainable. so yea battery may be the biggest consideration right now but back to the 3000 watt inverter if there's a 2.4kw load just from the minis it doesn't give me as much wiggle room as I would like so a larger inverter has to be considered.

Not sure where you got the average American house uses 15 kw per day… that would be very difficult to achieve in average America unless you were living pretty bare bones for a family In a house , condo or trailer. I would look that up again…

 

[JRH]

I have 14,400 watt hours of battery storage (12 Battleborn Batteries), 2/4000 watt inverters, 4100 watts of panels. I have two mini splits, No way will mine keep with that load and 90 percent of my 110 circuits. Just the mini splits use about 1200 watts in an hour watts x 2=2400 watts. Minus the hours that the sun is giving me PV which is about 7 hours, that means I need enough storage for 40,800 watts or 34 / 12 volt 100 AH batteries in a 24 hour period. Best be adding a lot of battery storage if you are planning to rely on solar 24 /7. Then if you have 40,800 watts of storage and are planning to charge them with PV and run your units while the sun is shining, then you will need 200 / 300 watt panels to charge the batteries and power the unit while the sun is shining. This is a tall order.

man.. I love the sound of having a system like that… I’m envious… ?

 

[camelCase]

I would spend my summers at higher elevations/latitudes where I wouldn't need so much AC

 

[johnim]

okay how many times do I need to bring up I expect 2 hrs of 2.4k draw then 1.2 max and probably not 17 hrs

 

[GLC]

how in the heck would you need 40,000 watts per day when the average American household uses around 15kw per day if memory serves. remember the minis will be around 1.2kw load for about two hrs worst case scenario because we are talking a 95 degree bus but once it cools down a bit less than half that...maybe 600 max. for my solar system best case scenario is about 15kw generated per day...that's 2880W x6 hr at about 85% efficiency but it's better than that. in any event a working plan for 15kw/day is very attainable. so yea battery may be the biggest consideration right now but back to the 3000 watt inverter if there's a 2.4kw load just from the minis it doesn't give me as much wiggle room as I would like so a larger inverter has to be considered.

Even with my solar, i still used 1400 kilowatts of grid power in June . And yes you may be able to collect 15 kw per day. I harvest 19 kw per day with my systems and still can't keep up in the summer. I am married in a 2400 sq ft home.

 

[RV10flyer]

I have 20,640 W of PV, 134 kWh battery, 18,000W inverter output. We use 60-80 kWh/day in the summer with 6.25 tons of high eff hp's, all electric home.

 

[johnim]

ok I did check my numbers and they are wrong...I doubled checked my home bill and at over June I used close to 40kw per day so that's a shocker. that said I don't need to run my home just my skoolie and there will be some trade offs but running one ac in a not too hot night can probably be done for 300w and by 10 that's 3000w and can be done along with running essentials with one 4800 ah battery. the problem as I discovered today is that u can have too little battery or too little sun but if u have too little of both well thats not fun

 

[johnim]

rf10flyer wow that's some serious wattage but remember I'm limited to the top of my skoolie. I got a pallet of 20 240V panels from santan solar and 12 barely fit running 2 rows of 6 front to back. I have been contemplating running the remaining 8 as 4 on each side that remain retracted at the sides but are easily deployed to 90 degrees with the aid of hydraulic lifting arms. that would give a potential 4800 watts potential and after all can you ever have too much of a good thing.

 

[johnim]

camelcase just saw your post what a great idea

 

[camelCase]

camelcase just saw your post what a great idea

I'm enjoying a mild Western Washington summer evening camping out in my truck camper. My batteries are full and no AC was needed. I highly recommend the summers here.