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points by elif 2 days ago | 0 comments

In the developed world you need lots of expensive batteries and a massive array to make that work. Unless you are like going without heating and cooling, you are looking at mid five figures to six figures in equipment alone.

You also need to meet NEC for all the wiring and if you put any on your roof, it will have to be approved by the building inspector.

Lastly, for firefighter safety you also need to have functioning and clearly accessible and labeled emergency shutoff inspected and approved.

To be honest upgrading the meter and applying for net metering was maybe 5% of the red tape hassle for my install.

[–] xedrac 2 days ago

You can get a 32kwh battery for about $3500. 12kw in solar panels is about $2500. And an inverter is a couple thousand. Throw in since mounting equipment and wiring, and a big system that can power a 4000 sqft home can be had for around $10k. If you want it truly off grid, you'll want a bigger battery and more panels to make it through consecutive cloudy days.

[–] elif 2 days ago

You'd have to send me the link but you are possibly comparison shopping scams. Are these alibaba or eBay listings maybe?

To have a battery that truly powers a whole house circuit breaker and not just one flakey ambiguous amperage draw rating collection of power strips you're looking at significantly more. And it's not just for cloudy days. You'd have to size your array for the winter solstice to not be constantly running a deficit out of summer.

Please correct me where I'm wrong with your actual lived experience, but ive yet to encounter much of that, mostly just "I googled this thing and found something claiming to be a thing I think might work"

[–] xedrac 1 day ago

I have two Yixiang power 16kwh wallmount batteries ($2200 each). The 32kwh battery is $3699. They work remarkably well and have EVE LFP cells and a JK bms. They are not UL listed, so keep that in mind. My system uses a more expensive SolArk 18k inverter, and these two batteries easily power my whole house through the night, even this time of year. It's not enough to be off grid 100% of the time, but where I live, it's probably close to 80% of the time.

[–] elif 1 day ago

Ya that sounds believable except the product you claim to have doesn't seem to exist

https://yixiangpower.com/collections/us-stock

[–] xedrac 14 hours ago

Yes it does. It's the "51.2V Vertical Battery Pack" with the 314 Ah EVE cells. I have two of them connected in parallel, communicating with my Sol-Ark 18k inverter via a standard Pylontech protocol for closed-loop communication. Maybe I confused you by describing it as a "wall mount"? The vertical batteries are very often wall mounted. I should have just said "vertical" instead. Anyway, they have been fantastic batteries. Two in parallel can discharge roughly 19kW of power continuously, which is more than enough to power all of the big loads in my home at the same time. The only downside of the batteries is you have to configure the JK BMS yourself. But there's a lot of community resources for that: https://docs.google.com/spreadsheets/d/1szaRxYzBHxwairtpCBBF...