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Comment by Kluggy | Hacker News Reader

My house faces east-west and so the local solar companies refuse to come out and give a quote. I know it's not going to be as efficient, but I live in an area with lots of power outages, so having a backup system is worth the lack of efficiency, but they all refuse to come out, no matter what I explain up front.

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> I live in an area with lots of power outages, so having a backup system is worth the lack of efficiency

Unless you go completely off-grid then rooftop solar isn’t going to help with outages as they are turned off during outages to protect electrical workers and the power grid. [1] Your problem can be solved with home batteries.

1. https://www.paradisesolarenergy.com/blog/will-solar-panels-w...

I was surprised to discover that even with a backup battery, a typical solar install is not designed to power your whole home in the event of a power loss. Only some inverters support it, and most backup batteries can't generate enough amps to start an A/C unit, even though they'd have enough to run it for a while.

Tesla's PowerWall is more capable than some, but I've heard nightmare stories about working with Tesla customer service so I stayed away from that one, even though technologically it's probably the most advanced.

> I was surprised to discover that even with a backup battery, a typical solar install is not designed to power your whole home in the event of a power loss.

Might even be illegal, depending on jurisdiction. For good reasons, you could kill electricians working on the local grid or firefighters working on your house if you're not careful with the install and adding local shut-offs.

My battery turns off when the grid goes down, but it has 3 outlets directly on the body of the battery, and those always work. I run extension cords from those when the power goes.

Bullshit. All "hybrid" inverters nowadays (grid tied + battery backup), auto island themselves when the grid is out.

That misconception is now 15 years old

That system is 5 years old. It feeds electricity back to the grid.

For an "auto island" functionality, I would need relays controlled by the inverter on all 3 phases between the electricity mains and my main switch box, right? I don't have relays like that.

The problem is in the "whole home". I'm pretty happy to have my lights/wifi/induction cooktop/etc. running when the power runs out.

How much electricity do you use? I have a low range inverter (5KW) and it can give me 4.5kw sustained power from my battery and as much as I want from the grid because it acts as a pass through. At 220V that's 20Amps, or 40A I guess with your American 110V supply.

Add another battery and bigger inverter and you can double that. Unless you've got a kiln or perpetually running hot water heating, I'm left baffled.

According to https://www.reddit.com/r/Generator/comments/15uy9dw/ac_start... an AC can require 79A on startup.

Though apparently there is a thing called a "softstart" that can be installed to mitigate this.

I don't actually know anything about this stuff. I just watch youtube videos.

Incorrect, please get a hybrid with the auto-islanding feature. I literally have a whole-house UPS and barely a blip when I get a power outtage.

So unless there is something magical about electricity in the USA, I'm not sure where this scare story is coming from.

I have one of these https://www.sunsynk.org/ourinverters

It's not AS efficient, true, especially in the winter when the sun is lower in the sky, but it's not like it'll do nothing - and in the summer you get a longer generation period. You'll likely need more panels, but panels (should) be cheap, although in the US you seem to have high prices due to tariffs.

Yes. It's a shame that it is hard to install on the ground - or rather it's a shame that permission isn't easily given for ground installations, if you have space. Ground installs won't damage your roof, and will be easier to clean, install, etc. But then, as noted elsewhere, is it really the answer anyway? Solar doesn't really give you the energy when you really need it - in the winter.

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