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Sizing Inverter Based on Home Consumption

Garage beer fridge was a shock to me, in the height of summer it was running about 23 hours a day at 180w, that adds up.
In the winter with no AC running, it was my highest energy consumer.
 
Garage beer fridge was a shock to me, in the height of summer it was running about 23 hours a day at 180w, that adds up.
In the winter with no AC running, it was my highest energy consumer.
Freezers don't like mixed climates with their small systems and wide temperature differential.
I've seen walkin coolers under normal operation at negative low side pressures guade of course
Larger accumulator or txv would help
But this would just reduce normal system efficiency or create another fail point
If you're in a warm climate you're around you could just install a line tap and lower the pressure to compensate
Bottom line no simple solution
 
@ Quattrohead Yup !
My favorite, is I had two electric wall clocks, and each consumed 14 continuous watts. Those both went straight into the wheelie bin.
They were replaced with two low cost battery powered wall clocks. One AA battery now lasts at least a year in each.

Another was my garage door opener.
It has a large continuously hot running transformer to provide 24v to the motor and radio receiver. This transformer was constantly powered and sucked up 70 continuous watts believe it or not.
What I did was separate out the radio receiver, and run that off a small 12v wall pack.
Now, when I push the button, that now energises a relay that powers up the big transformer only when its needed.
Absolutely no change to usage, but a MASSIVE drop in 24 hour continuous power consumption.

Once you know where the parasites are, its often not difficult to make some simple inexpensive change to dramatically drop daily power consumption.

Funnily enough its not the big loads that are only running for a minute or two, (microwave, electric kettle, power tools, etc..)
Its the small loads that draw continuous power that bleed you dry.
 
@ Quattrohead Yup !
My favorite, is I had two electric wall clocks, and each consumed 14 continuous watts. Those both went straight into the wheelie bin.
They were replaced with two low cost battery powered wall clocks. One AA battery now lasts at least a year in each.

Another was my garage door opener.
It has a large continuously hot running transformer to provide 24v to the motor and radio receiver. This transformer was constantly powered and sucked up 70 continuous watts believe it or not.
What I did was separate out the radio receiver, and run that off a small 12v wall pack.
Now, when I push the button, that now energises a relay that powers up the big transformer only when its needed.
Absolutely no change to usage, but a MASSIVE drop in 24 hour continuous power consumption.

Once you know where the parasites are, its often not difficult to make some simple inexpensive change to dramatically drop daily power consumption.

Funnily enough its not the big loads that are only running for a minute or two, (microwave, electric kettle, power tools, etc..)
Its the small loads that draw continuous power that bleed you dry.
Wow that's half the current of a running freezer
Very clever 👌
 
I think we are all very well aware that high idling power in an inverter is an evil thing.
But then we plug multiple small loads into it, that run 24 hrs continuously and think nothing of it.

Only by monitoring every appliance for maybe a day or two, then working out the Kwh consumption will you get the big picture, and the results are often quite a surprise. At least they were for me.
 
Thank you everybody for your responses and insights. I really appreciate everyone's experienced input.

I sincerely think my usage history report from the utility will be more than enough as a baseline. I was never planning to make my utility usage report my inverter bible. I downloaded my usage to an Excel file and did some fancy excel equations to determine my highest consumption hour was 7.73 kWh. To me an 8kW inverter would be minimum based on those numbers and a 10 or 12 would be better for fluctuations in demand (e.g. that turkey dinner or adding new loads). I think that is also backed up by the fact that my whole house (which is on a single breaker) is 100A (or 12k watts assuming 120V). I'm not using that much power at any given time, so I think a 10 or 12kW inverter would be enough for my needs.

That being said, I'm not looking to put every single kWh I use on solar/battery so if I find an inverter like the Sol-Ark that can parallel grid and battery to loads when necessary, I believe I can get away with a smaller inverter. Not saying that is the solution I will go with (it depends on price) but I don't think it is mission critical to have worse case scenario, every appliance on at the same time power flowing from the battery only.

I might still end up getting a usage meter and clamp my load center for a better understanding of what each circuit/appliance is doing, but I don't think it is critical for inverter sizing given I have data already from the utility. I have already used my kill-o-watt several times for various circuits in the house so I'm not really expecting any surprises (although, I've never done it for the garage door opener so I'm going to check that one :)).

Thanks again everyone. Now to find that inverter that can parallel power sources...
 
Screenshot_20240612-225920_EG4 Monitor.jpgScreenshot_20240530-213718_EG4 Monitor.jpg
This is a screenshot I just took on my 18KPV
If you notice the difference in what it's the consumption is VS what is taken from the batteries it's less than 70 W difference this is normally the case. I've never seen more than a 100 W difference and if you're in idle mode where you're bypassing it's like 18 W
Another thing this is a hybrid inverter so if I cannot produce enough power it can seemlessly blend the grid power it doesn't just switch over
The 18KPV is a 12 kW in inverter
 
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This is a screenshot I just took on my 18KPV
If you notice the difference in what it's the consumption is VS what is taken from the batteries it's less than 70 W difference this is normally the case. I've never seen more than a 100 W difference and if you're in idle mode where you're bypassing it's like 18 W
Another thing this is a hybrid inverter so if I cannot produce enough power it can seemlessly blend the grid power it doesn't just switch over
The 18KPV is a 12 kW in inverter
Basically what I'm saying if you're going to depend on the grid to back you up I would look towards a hybrid if not it's gonna be grid or solar/battery
 
Was your grid usage for today 0 kWh today then?

This is exactly what I will be looking for and I just started a thread for a list of these types of inverters.
I made almost 35 kW today off of 18-370 W panels
I'm still gathering materials to make a permanent array
I just installed the inverter just over 2 weeks ago

Screenshot_20240612-231558_EG4 Monitor.jpg20240530_070132.jpg20240530_070146.jpg20240530_070225.jpg
 
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Good luck do plenty of research before you make that purchase
Good quality unit should last 10 to 20 years plus. Granted no zombie Apocalypse
 

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