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diy solar

Rookie Getting Started w/ Home Backup?

json2001

New Member
Joined
Jun 26, 2023
Messages
10
Location
Virginia
Hi folks - brand new to this forum and to Will's youtube channel - amazing content.

Brief Context & Goal: I'm looking for some input on how I'm planning on getting started here. My home is on the grid and I have no backup power currently (no generators/no solar/no batteries/etc). I have what I would consider a reasonably complex, high load electrical system with 1x main panel with a sub-panel and then another panel that electricians have called a "disconnect" from the main panel. My goal ultimate goal is to work up to an automatic battery system that's able to provide emergency power to my most important circuits, but I'm also ok (and likely prefer while I'm learning) to start smaller/more simply.

I've explored solar arrays, but the company I consulted didn't offer battery systems and even seemed surprised I would want one. Google's Project Sunroof tells me I get "1,590 hours of usable sunlight per year." Given the estimated payback period of over 30 years and my house's reasonable amount of shade, I wasn't impressed with their system.

Current Plan: Initially, I may start with an Anker 767 and some portable solar panels. This would provide UPS to my server/router/wifi rack and offer an emergency power option for my fridge and other essentials. The solar panels would charge the device during prolonged blackouts (thinking I would temporarily set them up in my driveway in these situations).

Long-term Plan: Eventually, I want to install a permanent solution tied into my critical circuits directly. We honestly have had very few power outtages that last longer than a few hours since I've lived here, but I want the peace of mind that I have multi-day backup options for when those outages inevitably occur.

Given what the solar folks told me, it doesn't sound like a solar system would ever be my primary power source, but would be interested in possibly some panels to provide emergency backup to keep the batteries charged in a prolonged outtage. I could also be convince that a NG or multi-fuel generator might fit into my system for charging the system during a VERY long outtage. I'm very open to some of these DIY brands/systems and can see myself geeking out over certain components, but I would almost certainly pay an electrician to wire anything into my main panels. After that, I could see myself getting comfortable working on the batteries/inverters upstream from that over time.

There seem to be a TON of options out there and I'm trying to sift through them. I would greatly value your input on:
  1. My initial and long-term plans
  2. Any research paths and recommendations you might have for me.
Excited to be part of this community!
 
Determine your required peak watts, motor starting surge watts, watt-hours per day.

Find out what grid-tie net metering options are available from utility company. Can be a very good deal, if available ("store" power to use in winter or at night, without batteries.)

There is a range of prices from various brands. Some are single box all-in-one, some are components. A few with low-frequency 60 Hz transformers, many high-frequency.

I use SMA (Sunny Boy + Sunny Island). They have a high-frequency hybrid coming shortly (similar function as other hybrids many people here use.) Midnight has some high end (quality) and low end high-frequency products. Schneider has quality low-frequency products.
 
My system is for emergency backup only. I went with a 20kWh rack mount battery system and a 12kW all-in-one split-phase low frequency inverter. I don't have solar. For recharging, I have a Honda inverter generator (converted to tri-fuel) and a Chargeverter to convert that power directly to DC so the generator can feed the battery rack while the inverter powers the house via an interlock breaker and input box. The goal was to be able to run the house for most of the day and only get the generator out for a few hours to recharge the batteries. A secondary goal was to be able to power my 4-ton HVAC (with soft starter) in case of an outage during a heat wave. My Honda generator wasn't big enough to start up the unit. One benefit to the battery/inverter system is that you don't have to get out the generator for short outages. Another is that the system is quiet at night time, where the generator can be put in the garage for better security.
 
My system is for emergency backup only. I went with a 20kWh rack mount battery system and a 12kW all-in-one split-phase low frequency inverter. I don't have solar. For recharging, I have a Honda inverter generator (converted to tri-fuel) and a Chargeverter to convert that power directly to DC so the generator can feed the battery rack while the inverter powers the house via an interlock breaker and input box. The goal was to be able to run the house for most of the day and only get the generator out for a few hours to recharge the batteries. A secondary goal was to be able to power my 4-ton HVAC (with soft starter) in case of an outage during a heat wave. My Honda generator wasn't big enough to start up the unit. One benefit to the battery/inverter system is that you don't have to get out the generator for short outages. Another is that the system is quiet at night time, where the generator can be put in the garage for better security.
this is exactly what I'm looking to do as well! could you share some details about your setup?
 
I have a sol-ark 15k, 31kWh of rack batteries and 14kWh of diy, chargeverter, and a wen dg475t dual fuel generator with a bunch of 20# propane tanks.

Since it doesn't seem like you will ever sell back to the grid, i suggest something like a growatt 3k off-grid inverter and batteries. Buy the growatt that is stackable, so you can easily expand the system.
 
this is exactly what I'm looking to do as well! could you share some details about your setup?
Sure. Growatt 12k LF inverter, (4) Lifepower4 Batteries. I built the input power display using parts from Amazon. Chargeverter is not shown, but sits on top of the rack behind the laptop. Webcam is mounted above the input display so I can check power on both legs from my iphone.
 

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Sure. Growatt 12k LF inverter, (4) Lifepower4 Batteries. I built the input power display using parts from Amazon. Chargeverter is not shown, but sits on top of the rack behind the laptop. Webcam is mounted above the input display so I can check power on both legs from my iphone.
thanks!!! this is super-helpful! I see you have 30amps going out... would this setup work if I wanted to do a 50amp inlet?
 
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thanks! forgot to ask the charging question too... I see you have a 240 going in for charging... could I setup just a 120 for charging?
Yes, they make 120V battery chargers. My particular inverter requires 240V AC input and I use this to charge the batteries when utility power is available. During an outage, the generator will power the Chargeverter, sending it's power directly to the batteries while the Growatt runs the house. Without the Chargeverter, the Growatt would pass through the generator power, limiting what loads I could power. I may eventually upgrade to 50A, but so far I haven't needed that much current since I have natural gas for cooking, laundry and home heating. The HVAC inrush spike is high, but it only draws about 15A running.
 
Chargeverter is from Signature Solar and can supply up to 100A directly to the rack busbars. It plugs into the generator inlet/outlet to the left of the power display feeding the interlock when there is a power outage.

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