Mastodawn

One thing I've been meaning to do this year is some updates on our off-grid electric system, just in case anyone's interested, or looking to do it themselves.

I grew up off-grid for a while, so none of it was shockingly new to me, but even so, when we wanted to do it a couple years ago getting numbers was difficult, and installers always wanted to WAY overdo our system. In the end, I'm glad we put our foot down, and ended up doing a much smaller system than anyone(outside of a family friend who installs systems about 4 or 5 hours away from us) was willing to do.

So, now that my wife, myself, and our two boys are living off-grid full time, and living a fairly normal life as far as anyone in suburbia would be concerned looking in from the outside, I thought I'd start a thread that I could update over time.

As a side note, I was going to(or even may have) start this last year, but some damage to our system, and Helene, made it a weird year with downtime. Hopefully an outlier, but maybe not!

I'm also happy to try to answer any questions that anyone might have about any of it.

That all said, we have 7.2 kW of mono-facial solar panels, ground mounted on a hill above our cabin. We have a fairly long electric run, all underground, into an old shed that had a much older system in place when we moved in. We replaced all of that equipment with a new Victron system and EG4-LL V2 LiFePO4 batteries. We have 60kWh of batteries on a 48V system.

That runs to two buildings, one of which is our main cabin and the second is a very small little two room(main room and bathroom) building that may have once been a mother-in-law suite or something like that. My wife uses it as her office space now.

In our main cabin space we added an EcoFlow smart home sub-panel a few years back which all of our circuits runt through. We keep two Delta Pro "solar generators" each with an extra battery on hand that we can run the cabin fully off of as an approximately 15kWh backup.

We also have a small gas powered generator(WEN DF875iX) that we try not to use, but particularly when the system was damaged, we do from time to time. Since we drive off of our property almost zero, the gas used for the generator, and our kei truck to drive around on our property is the vast majority of our gasoline usage. So far this year we've purchased 15 gallons and used about half of that.

That all said, and I'll try to remember to do this quarterly, from January 1st to March 31st this year we had:

-610 kWh of solar generated in January

-579 kWh of solar generated in February

-679 kWh of solar generated in March

-1868 kWh of solar generated in total YTD

-In February we did have a couple of days where we ran the generator. We ran ~5 gallons of gasoline for a total of 35 kWh of power.

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A Concerned Scientist May 1, 2025

A few general things to add to that.

We are not even connected to the grid, so when our batteries are full, our solar panels only put out enough to cover what we're using. So the numbers per month are really more like a "minimum" of what we could get from our panels.

When the weather's fairly sunny, we top off our battery bank around noon most days, so the afternoon sun is only partially used.

Also, we are still trying to get the small stream hydro-electric system on site up and running again. It's one of those "every time you fix one thing, something else pops up" situations. We were pretty much there until Helene and we just haven't gotten around to fixing the pipes after that, although I think it might hit the top of the to-do list soon.

Our calculations lead us to believe that we could get upwards of 18 kWh a day from that at its seasonal max, as it sits, but the professor we consulted with before we bought the property some years back said in his experience we'd probably get around 15 kWh if it was all dialed in. Frankly, if we got 10 kWh we'd probably never have to fire up the generator again. So that's the long term goal.

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A Concerned Scientist Jul 7

Our second quarter this year, we had the following energy data:

-764 kWh of solar generated in April
-We ran the generator for ~38 kWh worth of power and a little over 5 gallons of gasoline early in the month.

-834 kWh of solar generated in May

-889 kWh of solar generated in June
-We ran the generator for ~134 kWh using about 19 gallons of gas.

June was a really weird month. It was hot, including some time in a heat dome, but weirdly not that sunny.

Early in the month it was constantly lightly hazy from distant forest fire smoke, which seems to knock the solar output down ~15%. Late in the month every single day the forecast was for 40 kWh of solar, and every single day it was sun for a few minutes, then clouds for a few minutes, back to sun for a few minutes, back to clouds, etc. for most of the day. Which leaves it very hot, but only gives you about half your solar output at the end of the day.

Unfortunately, I ran that by a climate scientist I know, and he said it is very likely to be more common in the future. This has got me thinking about expanding our solar some, but for the moment we're rolling with it.

I know in the grand scheme of things 19 gallons of gas in a month isn't that big of a deal(we have basically zero driving gas, so the generator is well over 90% of our total used...every now and then I throw a splash that would have gone to the generator into our kei truck to haul stuff around the property), but, I'd really like to be at zero gas usage eventually.

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A Concerned Scientist Jul 7

Also on the topic of solar; solar generators.

We have a greenhouse with a main exhaust fan as well as two fans in the middle to help move air. Being off-grid, we had to figure out how to power that ourselves.

We re-purposed old solar panels, ground mounted on the hillside above the greenhouse that are putting out about 900W mid-day. We ran that into an EcoFlow Delta Pro that was being used as backup on our cabin and we moved up to the greenhouse.

Turns out, that wasn't quite enough power, so we supplemented it into a little battery bank we also had sitting around and 2x 200W panels that we had sitting around.

That was working OK, but given two different systems with inverter losses and whatnot we were still running a little behind and had to haul it all down to the cabin to charge every week or two.

At that point I started looking for a solar generator with dual solar inputs, so I could run both the already ground mounted panels above the greenhouse alongside another set of panels and have enough power to run it all together into one.

Turns out while I was looking, Anker Solix came out with an "F3000" solar generator that seemed to fit the bill, and because it was just coming out, it was on a release deal for about $1100 less than the closest comparable EcoFlow. Seemed great!

After running the Anker for a few days now, if you're looking for the tldr, don't buy into the Anker Solix ecosystem. I've run into multiple problems and their support just shrugs, says that's the way it is and they aren't planning on ever updating the software or anything.

Some of my grievances:

- Cloud only. My bad on this one. I thought there was a functioning Home Assistant integration and there is for many Anker Solix, but their F3800 and F3000 don't work with it.

- Since it's cloud only, you really need it to connect to the internet. It just wouldn't not connect to my WiFi until I had it sitting right next to an AP.

- Once it finally connected, it said it needed a firmware update. It failed over and over and over, rebooted itself, failed again, then finally successfully completed it. I have a bad feeling this thing is going to brick itself one day.

- Finally got it up and running, and the charge controller losses are worse than I've ever seen. Generally MPPTs are 95%+ efficient, bad ones are like 92%, but this thing loses a minimum of 12% just bringing DC power in and feeding it to the batteries.

- The software does not have charge or discharge limits. It's literally mind boggling that a modern system won't let you set that. So now I have to constantly keep an eye on it because I don't like taking my LiFePO4 batteries down below 20%.

- It has dual solar inputs, right? That was the whole point. Well, they don't let you see what goes into each one! They just have an already added number between the two.

Their support response to any and all of these issues? Basically, "Sounds about right. We are not planning on ever updating the software, so whatever it does it does. Deal with it. If you want to return it in the first 30 days, you pay shipping. It'll be ~$500. After that don't ever bother us again."

Given that I just had a bunch of Eufy(another Anker brand) cameras that they bricked with a firmware update that I couldn't schedule or reject a couple months ago, and their response to that was "That sucks bro. Here's a $10 off coupon so you can buy more of our crap" I'm out. No more Anker, ever. I didn't even realize they were the same company until I got the same crappy support from each of them.

Edited for a couple egregious typos

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A Concerned Scientist Jul 11

So, my tldr of don't buy into this system turns out to be more immediate than I anticipated.

Around 6AM this morning, while my Anker Solix F3000 was outputting ~25W for a couple thermostats and an access point, it died.

It powers up directly off of solar input, but as soon as you disconnect the solar it shuts down, and it won't put out AC power at all.

This thing costs $2600 and lasted for 6 days. They'd better not try to charge me $500 to ship it back to them...

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A Concerned Scientist Jul 23

Anker apparently only has a warehouse in California, we're on the east coast, and big battery banks like this have to be shipped via ground shipping. So, 11 days later we finally received a replacement today.

I will give Anker credit where it's due, though. Tier 1 support got tired of me and moved me onto tier 2 support. They listened to my issues with it, and while they might just be giving lip service to a lot of it, they have already worked up a beta for me to test of the software with charge and discharge limits that they are hoping to release next month for everyone. They say that they are working on giving a way to see what's going into each solar input, and they are "exploring" the possibility of the "Works With Home Assistant" program.

Will any of those things come to fruition? Will this solar generator last more than 6 days??? We'll find out!

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A Concerned Scientist Jul 30

One week update, and I'm going to preface this with two facts so that I'm totally up front.

-One, they gave me a free ~$1500 item in return for my testing and ideas.

-Two, I feel bad because they really seem to be trying(and I'm pretty sure after one conversation I had with them that they read this one way or another, so, hi!), but this is a poorly thought out product and ecosystem. Don't get into it.

A couple quick points, rather than me doing a whole scientific paper on this thing, like I tend to do.

-Since they don't have any way to log data, which is semi-unforgivable, I spent the week taking data points of power in, plotting them, and using a Reimann sum to find an approximate total solar input. I used smart plugs out of it that automatically gave me exact Wh usage.

-Using that data over a week, at first I was stumped that it somehow used it's entire battery bank despite the fact that I put roughly 37 kWh of solar into it and only used 28 kWh of power. Yes, all systems converting AC power to DC power and back have losses, but no matter how I calculated it I kept coming up with 33-35% losses, and that's just a lot.

-After some back and forth, and a "tech team" looking into it, the long story short version is that they seem to use an extremely power hungry inverter. It uses upwards of 70W just to keep the thing powered on. Which, doesn't seem like a lot offhand, but think about it like this:

Over a 24 hour period, not using any power, just to keep itself on it'll use ~1,680 Wh. The entire battery bank is only 3,076 Wh. It uses 55% of its own power just to keep it turned on for one day if you're not constantly feeding it external power.

For comparison's sake, as I've said previously, I've used EcoFlow's Delta Pro solar generators for years. They're very comparable in terms of size and ability to the Solix. While they aren't perfect, their inverters use under 25W.

Bottom line, extrapolate that out, and over a week rather than the Solix being dead and needing an external AC charge up, the EcoFlow would have been at 100% battery.

-So what's the use case for the Solix stuff, and what was Anker thinking? I honestly don't know. There's really just two options here, as far as I can tell.

One, they only anticipated it being used for a couple hours at a time, for short power outages.

Two, one day they woke up and were like, "Hey, we sell battery banks. What if we sold really big battery banks?" and didn't think it through much further than that.

Sadly, given the interactions I've had with tier 1, tier 2, tech teams, product management, etc. I am inclined to believe that the latter is what happened. They don't understand the market. They don't understand the uses and limitations. They seem to expect that you're just going to use it for such large loads, and short times, that the losses are minimized.

-They've already permanently dropped the price on the thing by 30% before it's even been out a month. They know it's not a great product.

tldr; Second one lasted more than 6 days. Yay! There's still major firmware/software limitations, which I do think they're working on. There's sadly also hardware limitations that severely limit the use case.

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Chuck Jul 30

@BE Excellent discussion. If you do get a micro-hydro setup going you could put in a reservoir pond on the hill where your panels are and pump water up there with excess solar power to reclaim later through the microhydro system. We’ve had similar experiences with the “off the shelf” solar generators, we had been building “battery boxes” before it was a thing and agree that the manufacturers don’t know their market. 1/2

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Chuck Jul 30

@BE One of the things we did with our battery boxes was a timed disconnect relay, if the inverter isn’t supplying power for > 2 minutes it turns off power to the inverter. When you plug something in you push the ‘on’ button and things start up (the ‘on’ just energizes the relay, the load on the plug keeps it on) I have a “smart outlet” that I’ve looked at using for this too. 2/2

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A Concerned Scientist Jul 30

@ChuckMcManis

We've been thinking about pumping water uphill for use later like that! It's a pretty neat idea and something we'd like to do in the longterm plan.

Eventually we always planned to just put in our own system with some Victron equipment in the greenhouse, but after having very good luck overall with EcoFlow, we figured we could get away with another similar system to get the greenhouse powered in the short term, and get food growing. Not turning out to be a great decision with the Solix.

For now I'll have to just keep re-charging it weekly while cursing Anker's engineering decisions under my breath the whole time. One of which, by the way, that I didn't even get in to, is that they made the box itself portable with wheels, but then sell an extra battery that you put on top of it, that both doesn't attach AND doesn't have wheels so it makes the whole thing functionally non-portable as soon as you expand it.

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Chuck Jul 30

@BE Bummer on the extra battery. We have built so many battery boxes at this time that we even have our own wiring standard 😃 We use powerpole connectors for interconnects, with red/black being connections to DC (batteries), white/black being connections for inverters to the battery packs (fused), and green/yellow for connection of solar panels to charge controllers. Bought an official crimper even (and one for MC4 connectors).

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A Concerned Scientist Jul 30

@ChuckMcManis

That's awesome! Over the last couple of years I've gone from semi-comfortable around solar power systems and understanding the basics of how they work, to being pretty sure I could design and build out a system myself without any real issues.

Just started crimping my own MC4's this year to re-wire and re-purpose old solar panels that were already ground mounted on the property from the 80's and another set from the early 2000's. I figure eventually I'll harvest the LiFePO4 batteries from the EcoFlow/Anker systems and re-use them as I'm betting the batteries will long outlast the other components.

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A Concerned Scientist Oct 6

Solar update time!

One note, starting in June of 2024 we began living here full time, so during this last quarter we went over a year fully off grid.

In that time we've managed 87.3% of our power from solar, and the other 12.7% gas-powered generator. The obvious goal to bring that closer to 0% generator over time.

Because we work out here in the woods, and the kids do virtual school, we use very little gasoline beyond that. Just a couple tanks of gas overall.

- 906 kWh of solar generated in July

Unfortunately, with an early month heat dome dragging in from June, and then another heat dome a couple weeks later, it was hot, and we ended up running our heat pumps a lot more than we thought we ever would.

- 261 kWh from the generator using about 35 gallons of gas.

After July we evaluated our situation and added 1600W of solar on ~10 kWh of batteries that would be dedicated to emergency home backup or exclusively powering two mini splits next time it's that hot. So hopefully next summer we won't see a repeat, even if we spend a lot of time in heat domes.

- 626 kWh of solar generated in August

If you're thinking that's a typo, it's not. It was the dreariest, cloudiest month until the end of the month. We had exactly 4 separate days that we saw the sun. About 150 kWh of that came in those 4 days at the end of the month.

In August of 2024, for comparison, we generated ~275 kWh more than that from solar.

- 269 kWh from the generator using over 36 gallons of gas.

This was the first time we *really* wished that we had our micro hydro power repaired and working.

- 704 kWh of solar generated in September

Again, a long streak of completely cloudy days hit from the 17th - 25th, but at least this time it was cooler and we used less power.

- 103 kWh from he generator using under 15 gallons of gas

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A Concerned Scientist Oct 15

Minor update.

As of today it's been exactly 1 year since we were able to do the fairly minor repairs we needed on our solar after Helene.

At the time we went ahead and re-ran about half of our 500' electric run, and put in a junction box on a pole at about the halfway point. With all of the excavators around western North Carolina on emergency duty at the time, I dug the whole thing by hand, and had to work down to the main road, and a bit beyond, cutting trees out of the road so our solar installer friend from the east coast could come help us out and make sure we got all of the wiring correct.

But it's now been 1 full year of 100% uptime for our electric system!