Help finding an inverter based upon features and quality

[LTC-J]

I'm in the process of designing a semi-whole house solution that I'm planning to use as a big UPS... fridge, freezer, well pump, 3kw computer equip, and 2-3 rooms. I get winter power outages(snow + trees) and summer wind outages.

Initially, charging will be grid when available and generator when power is out. As things allow, I'll add in solar and potentially windmill(a bit of wind in my area) or water wheel(small year round creek on property)

Right now, I'm starting research/shopping for an inverter. I believe I want a 48v system. I believe I want split phase(240V single phase) I believe I'm looking for 12kW or more inverter capacity.

First thing I'm looking for is quality. Are there must avoid companies? What about 'must do' companies? I won't say cost isn't an issue but I will 100% pay extra for quality. I'm talking about internal components as well as 'external' connections/lugs.

Second thing I'm looking for is regular hardwired/networked interface; I want it plugged into my 'diag' network that I've got a computer plugged into. I have less than zero interest in blue tooth interface or using my phone for setup, monitoring, or diagnosis. I realize this is probably an impossible but this is strong wish.

Third thing I'm looking for is simple/basic in terms of features. If I could find a black/yellow box that says inverter, I'm sold

<first post, thanks Will for the videos and pointing people here>

 

[sunshine_eggo]

Link #1 in my signature - Energy audit.

You must define your loads and energy requirements as accurately as possible.

 

[danrclem]

Link #1 in my signature - Energy audit.

You must define your loads and energy requirements as accurately as possible.

I went to the link and downloaded it. It didn't come out in English letters. What am I doing wrong?

 

[Hedges]

Sunny Island (available liquidation prices on eBay) could make a 12kW or 24kW UPS.

Commercially available lithium batteries supporting closed-loop BMS with SI are more expensive than others. There are DIY options. I'm using AGM because grid-backup, infrequent cycling.

Supports AC and DC coupling of sources.

Its firmware does not have the peak shifting options that many newer models/brands do.

 

[Rocketman]

I would look at Victron- it will be more expensive, but it is high quality and has lots of data information on VRM.

 

[scrubjaysnest]

I went to the link and downloaded it. It didn't come out in English letters. What am I doing wrong?

Worked fine for me in excel 2000. Does have a few holes for my use though.

 

[LTC-J]

Link #1 in my signature - Energy audit.

You must define your loads and energy requirements as accurately as possible.

Funny enough. I had that printed out before starting thread The issue I have with it is it assumes that any 'appliance' added to the list is always running. We know that isn't the case for most items. It is also what got me started at ~12kW plus a bit:
Fridge 1kW
Freezer 1kW
well pump 1kW
Furnace fan 2 x 1kW
Microwave 1kW
Comp stuff 3kW
Misc around house 1kW (lights, TV, etc)
Surge (well) ~2kW
The above is ~12kW... they are also overestimated by a bit but I'd rather oversize my inverter than do many inverter upgrades If I assume 24/7 electric drier, I would add another 6kW.

I've also got a few years of electric company usage to give me an idea of daily capacity use so I can hit overall battery number to what I want.

I've got a mild budget in mind but I will sacrifice battery capacity at the initial buy to get the 'best to me' inverter.

 

[Brucey]

Is your comp stuff actually using 3kW or is that just the nameplate power supply values added up?

 

[Hedges]

For things like refrigerator and laundry, there are consumer energy labels (in the US), with some assumption of use pattern and climate.

Past utility bills is great for kWh/day.

Air conditioner?
If only needed daytime, great for PV.

 

[sunshine_eggo]

Funny enough. I had that printed out before starting thread The issue I have with it is it assumes that any 'appliance' added to the list is always running. We know that isn't the case for most items. It is also what got me started at ~12kW plus a bit:
Fridge 1kW
Freezer 1kW
well pump 1kW
Furnace fan 2 x 1kW
Microwave 1kW
Comp stuff 3kW
Misc around house 1kW (lights, TV, etc)
Surge (well) ~2kW
The above is ~12kW... they are also overestimated by a bit but I'd rather oversize my inverter than do many inverter upgrades If I assume 24/7 electric drier, I would add another 6kW.

I've also got a few years of electric company usage to give me an idea of daily capacity use so I can hit overall battery number to what I want.

I've got a mild budget in mind but I will sacrifice battery capacity at the initial buy to get the 'best to me' inverter.

It's up to you to make the numbers work when you know better. if a fridge uses 365kwh/year, you check the data plate rating and apply the correct number of hours to that power to get 1kWh/day.

Sometimes a general guide like this:

Off-Grid Solar System Sizing Calculator

Our Off Grid Solar System Sizing Calculator will help you size the battery bank and watts of solar power, you need for an off-grid solar electric system. | Solar BiZ

www.thesolarbiz.com

gets workable numbers.

Bottom line is that an earnest effort generally yields a workable design. Swags usually mean too much $ or not enough system.

 

[LTC-J]

Is your comp stuff actually using 3kW or is that just the nameplate power supply values added up?

It is very close. I was unable to run desired equipment on a single 20A circuit

For things like refrigerator and laundry, there are consumer energy labels (in the US), with some assumption of use pattern and climate.

Past utility bills is great for kWh/day.

Air conditioner?
If only needed daytime, great for PV.

Aside from fridges, I can control a lot of the concurrent loads and surges. I was able to run both fridge and freezer on a 2000 watt generator plus a small electric blanket during a recent snow storm.

AC is kind of optional. I get maybe a week of over 100F a year.