OffGridInTheCity Build

Bummer. Smoke is no good, and there's not a thing you can do about it! I wish I could send you some of our East Texas sunshine. It's 108 degrees today, and we haven't seen a cloud (let alone a drop of rain) in more than a month. Even around here, that's a bit unusual.

I realize this forum is all about solar electric and so forth, but this summer has given me new perspective on other utilities. For example, at my ranch, I have a spring-fed lake that is still running water at the overflow. I also have an irrigation well, so functionally I've got unlimited water supply independent of the weather. On the flip side, at my commercial office building, my water bill last month exceeded $400 -- most of which went toward keeping the lawn and landscaping alive in this heat. Lesson? Always focus on a property with water rights where you can drill a well, collect runoff, pump from a lake or creek, etc.

Cheers, John
 
Maint Update: 3rd (of 4) Progressive 240v/120v ATS had to be replaced this week. As in the other 3, it's been ~4years / ~2400 switch-overs and started to stick a little / wouldn't complete the switch.

Obviously I'd like a longer lasting solution, maybe a non-mechanical ATS or maybe an APC model (more robust?) of some kind but I need the 240v/120v @ 50a else I'd have to do major rewiring. These Progressive ATSs - https://www.amazon.com/dp/B003VAWNVK - are up to $186 each.
 
OGITC: It may not fit your application, or even what you might be considering...but check out the surplus guys in Ft. Calhoun Nebraska. They are selling manual transfer switches originally designed to provide power at cell towers. New in the box, incredible build quality. They use Square D QO for the circuit panel portion, and have transfer bar manual switching for 2 generators. But the best part (arguably) is the super high quality surge protection system on board. They are UL approved as service gear too. 100 amp.

I bought 2 of them, and one is going to be installed soon in the property we have that was damaged by the 2020 derecho. Making some progress finally.

I've bought a few things from them over the years, and have found them very good to do business with. They have thousands upon thousands of bizarre items...be prepared to binge surf their website.....
 
OGITC: It may not fit your application, or even what you might be considering...but check out the surplus guys in Ft. Calhoun Nebraska. They are selling manual transfer switches originally designed to provide power at cell towers. New in the box, incredible build quality. They use Square D QO for the circuit panel portion, and have transfer bar manual switching for 2 generators. But the best part (arguably) is the super high quality surge protection system on board. They are UL approved as service gear too. 100 amp.

I bought 2 of them, and one is going to be installed soon in the property we have that was damaged by the 2020 derecho. Making some progress finally.

I've bought a few things from them over the years, and have found them very good to do business with. They have thousands upon thousands of bizarre items...be prepared to binge surf their website.....
Thank you for the tip, however, in my setup I only use automatic transfer switches.
 
5yr old 18650 solar generator still works....

Got my 'DIY solar generator' out of storage (55F-75F ambient) the other week to supplement a 3-day camping trip where there was no power. It's a 7s60p 18650 2nd hand cells from 6 years ago and ~3.3kwh. It's got a Reliable 1500w 24v inverter and an MPT-7210A that I feed with 120v->24vdc for 120v charging.

I think I left it at ~3.7v and the packs were still ~3.5-3.6v after 5 years. Not sure exactly but the packs remained amazingly stable over that long period of time. It charged (and balanced) right up to 4.1v as if I'd just built it. I used it to feed about 2.5kwh into the trailer's MPP Solar 3048LV AC input while camping to get a little over 2kwh charge into the camper batteries.

Amazing... I post this because over time it seems like a lot of (negative) discussions about cells sitting for long periods... but from what I can see thru this experience, they are quite robust.

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2023 is complete! Updated the 1st post with 2023 stats....

Consumed 14,695kwh bringing the lifetime total to 72,256kwh.
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Added battery #9 and completed 1,874 cycles with average 36% DOD.
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Finally, consumed 23,122gal of rain harvest water in 2023, bringing the lifetime total to 87,982gal
 
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Thank you @Wolf - very thoughtful/kind! :)

Here's my new setup courtesy of @Wolf sending me his older OPUS 3100s. He's done the fan mod to enable 1000ma discharge tests. Mine always overheated so I've done all 14,000 cells at 500ma discharge till now. And... the noise level is very quiet - a bonus.

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Added @Wolf's fan mod to my remaining good one and suddenly I'm up from 7 flakey slots + 4 good slots to 16 good slots with 1a charging capability!
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Found one more old one where I tried a fan repair that never worked right as I had to start the fan spinning with my finger as it wasn't a good match to the OPUS.

Ordered a fan + rubber feet and I may get up to 20 working slots! OH MY! Start thinking of battery #11?
 
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DISASTER FIRE tonight at 1am'ish. Neighbors OK except the fence and at least one is likely very angry.

The generator shed caught fire which in turn caused the 10 x 100lb propane tanks behind/under the PV array to vent causing MASSIVE FIRE shooting 30ft in the air. Looks like the generator exhaust (thru the wall) caused some smoldering in the wall and the wall of the shed eventually flamed (12hrs later or couple of days later) and started heating/igniting the propane tanks behind it.
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**I did the exhaust over a year ago - repeated tests, temp checks, thought it was OK but 99% sure this is the ignition source. Didn't realize a fire can smolder - the 1st investigator said that it's possible that as low as 200F can get framing wood smoldering.

All of this burned. Water tanks, PV array completely gone - 2" galvanized pipe warped from heat. Shed a loss.
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Will post some pics in daylight.
 
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Man, glad it was just the shed and no one was injured

The only major issue I see here is that propane tanks were stored near an exhaust port. This is spooky to me. If the generator is running and there's a slight breeze to push the exhaust towards the tanks, and the tank was full, this alone could cause the tanks to start venting and some other source spark the flame.
Second I'd have at least put an upspout for the exhaust on the outside, just so that it wasn't shooting straight out. A single 90* with a 6"-12" riser would be enough to keep it away from anything. Well, other than the solar panels directly above, which raises other questions 🤔
However, I didn't realize that wood would start smoldering at 200F. Good to know for future builds.

Curious, how many walls is the exhaust pipe? I know here gas water heater exhaust must be minimum 2 walls. I would imagine a generator exhaust would get hotter than a water heater exhaust.

Definitely a learning experience for everyone involved and who reads this post.
 
Fire pics
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Surprised the panels are GONE and 2" galvanized pipe bowing/crooked here and there - other than shards of glass strewn all over, there not much left.

A real bummer - so much work up in flames within an hour.
 
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Man, glad it was just the shed and no one was injured

The only major issue I see here is that propane tanks were stored near an exhaust port. This is spooky to me. If the generator is running and there's a slight breeze to push the exhaust towards the tanks, and the tank was full, this alone could cause the tanks to start venting and some other source spark the flame.
Second I'd have at least put an upspout for the exhaust on the outside, just so that it wasn't shooting straight out. A single 90* with a 6"-12" riser would be enough to keep it away from anything.
I had a baffle box over with rockwool - like a large muffler - over the exhaust hole and exhaust went down. Recently added it, not in pic. I could put my hand in the exhaust temp wise it was not hot.

Repeatedly - at least 20 times over the last year - did generator runs, shorter, then medium and measured temps etc. Thought I was being safe but recently started doing a couple of 60minute runs to measure efficiency.

Well, other than the solar panels directly above, which raises other questions 🤔
However, I didn't realize that wood would start smoldering at 200F. Good to know for future builds.
Curious, how many walls is the exhaust pipe? I know here gas water heater exhaust must be minimum 2 walls. I would imagine a generator exhaust would get hotter than a water heater exhaust.
Yes, right at the Champion exhaust port it was 500F+ but the exhaust pipe was 4ft long before going thru the wall. Here's an older pic where I *recently* (3 weeks ago) replaced the high-temp flex silicon 1.5" diameter exhaust pipe (doesn't transmit heat) in the pic with a flexible metal 1.5". In fact this metal may have transmitted heat from generator exhaust port to the hole in the wall where the flexible silicon didn't.
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Definitely a learning experience for everyone involved and who reads this post.
Agreed. I for one, will NEVER
1) Try to run a generator in a shed again....
2) Store propane bottles next to anything flammable - like a outside wall. I never thought of a shed wall as being flammable but that's my bad.

And of course I feel terrible..... and the neighbors are not happy. DIY has risks for sure.
 
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That sounds like a florida man story..
I'm glad you're doing well and that no person got hurt, just parts. Thanks for sharing the story and pictures.
 
Some details....

* Fire dept investigation concluded that generator exhaust thru the wall cause smoldering fire in the wall that eventually caused flame.

* Aluminum Iron Ridge Top Caps - https://www.ironridge.com/component/top-cap/ in the propane fire area melted into slag on the ground...

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leaving the horizontal 2" galvanized hanging free, no longer supported by the vertical pipes.
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Never thought of a metal PV array as vulnerable to fire like this or that Aluminum is a weak point. Panels yes, but framework? The galvanized pipe, universal struts, and ubolts all held up. Warped and need a lot of replacement but did not catastrophically fail. Aluminum was the weak spot.

* The panels are gone! but there are glass shards all over the back yard in the grass - will require detailed cleanup.
 
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Never thought of a metal PV array as vulnerable to fire like this. Panels yes, but framework?
You're talking about Propane that is being force fed. The more heat generated, the more oxygen is pulled into the "torch" flame, the hotter the flame, the more oxygen is pulled in.....

Propane is the goto choice making DIY kilns at it can get hot enough to melt most metals in a very short period of time. You basically had a large kiln here, just didn't happen to be inside of a thermal insulated container
 
wow, a horror story by the looks of things. How far away are your 18650 cells?
 
wow, a horror story by the looks of things. How far away are your 18650 cells?
About 250 feet. Of course one rethinks the 18650 powerwall but with Batrium and constant monitoring and low stress charge/discharge and 6 years of operation - I think of it as safe.
 
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I hope you can recover eventually.
That's the plan

The neighbors.... they must hate you.
We visited the 3 affected neighbors that border the back corner of our property and apologized and offered to help what we could that's not in conflict with insurance process. In my mind, things should be manageable but it's not up to me. Very different responses.

State Farm (home insurance) apparently doesn't respond over the weekend - national web portal only, filed the initial claim. Local agent didn't return a message. Fire dept concluded their investigation yesterday but advised against cleanup till State Farm decides if they want to do their own investigation.

It's a helpless feeling. And in the background, I feel like I've let myself and the idea of off-grid DIY down a bit. Tried to be safe with generator but didn't go far enough or succeed in the end.
 
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