Building a barebones SHTF Emergency Energy System

[keepdoing]

Hello,
I’m david. Live in the north Georgia mountains. Latitude is about 34.5. I have about an acre and a half on a small river and I am starting to work toward independence. The ENTIRE basis for wanting to do this is in the event of grid meltdown / societal meltdown, which could go months or a year. I think it is just a matter of when personally. So all of this is based around designing a system that does the emergency basics I outline – and lasts as long as possible for the least investment.

I’m thinking about starting with 500 Gallons Propane. It’s dirt cheap now, can run my little Duromax FlexFuel Generator (4400 Surge / 3500 Consistent Watts). At 50% load it says it will run 20 hours on a barbecue tank. If we call a Barbeque tank 4.6 Gallons of LP, then they are basically claiming around 4.38 hours runtime at ½ load per gallon. I’m not buying that, and am calculating maybe 2.5 hours/gallon at ½ load (or 1750 watts/hr). That may even be pushing it. But at 3 hours of run a day I get maybe 10 months runtime for the following….

I WANT TO FOCUS ON a freezer, a fridge (about 700W each) some circulation fans and a Dehumidifier (?) as the main things that may need running. Cooking would be handled from a stack of smaller BBQ Bottles (not the 500 tank). I’m thinking about a portable LPG camp water heater, either off the 500 – or a few smaller tanks. One of my philosophies is that IF things really get that bad – there ain’t going to be many daily showers. And the power is only needed a few hours a day if that to keep the basics going / house from turning into mold etc. And I’ll have Solar Heat Collectors for “Base Heat” in winter that can be spot augmented by my “Big Buddy’s” that can be hooked to the 500, or individual bbq tanks.

Now, that’s my starting plan. Next phase is to extend the finite running life of the system with solar. And then I get stuck on all the dang batteries, inverters etc. What I want to do is actually bypass batteries altogether on a solar install. Propane is ultimately finite. So are batteries. If I consider that I only want the bare bones basics of refrigeration and dehumidification, and save the bulk of the propane energy for spot use to augment for splurges or cloudy days, then I could probably just hook solar direct to all my stuff and simply take advantage of it when the sun shines???? Should keep ahead of the humidity and keeping things from thawing most of the time with limited generator help. And of course – there would be some excess power in the system when sun is shining or generator running, and then we live like kings! With led lights blazing in a few lamps, and maybe we microwave some of our homegrown popcorn LOL If lucky we run the little AC unit an hour or two sometimes

I have very finite money. My questions are simple….. I guess I need some sort of inverter, but do I really need Sine/ Modified Sine / True Sine? Assuming a max solar wattage of say 1.5kw coming in at any given time – direct to use, skipping batteries, what is the cheapest way to work this? What drawbacks are seen? Keep in mind that I am pretty much content living on the grid. It’s cheap and easy. While nice to recoup investment as I plow along, the real and pretty much only reason for this is as an emergency energy insurance plan. If that turns out to be a couple week blizzard – the neighbors think I am a genius for a time. If nothing ever happens, know one really knows I’m paranoid nuts but you guys here But if something does go wrong, and I think it will – my family genes are better prepared to survive and keep filling up the earth with humans. Hopefully a better batch than we currently have.

So…. Any feedback on how to accomplish my approach in most economic, longest lasting closed system manner? And again, in MY scenario – things may go out and stay out – for a LONG time, and I prefer to focus on maximizing the time I have the basics, than luxury aspects (like daily hot showers). Going to miss those

What I am looking for is basically a suggested "Parts List". And trust me - I have already researched so many possibilities I am exhausted. Finally figured I would direct ask someone. Thanks in advance for any thoughts.

Peace,
- david

[lkruper]

I am not a survivalist and so have not thought out things like you have, but what do you need a fridge/freezer in that scenario? You won't be able to get groceries at the supermarket then, right? Perhaps you would be better served with something like Mountain House freeze dried food that lasts 25 years and requires no refrigeration. I have a month or so at my cabin just in case El Nino cuts us off from supplies next year.

That being said, the one area in which my interests intersected with yours was the question regarding whether or not a refrigerator could run directly from solar. I was looking at some energy efficient ones like Engel which run off of DC and therefore don't need the inverter, but most of what I read have a battery also. I am not sure if that is to provide cooling when the sun is not shining or whether or not even the Engel draws too much when the compressor starts up. Perhaps a solar fanatic here has the answer to that one.

[solarix]

Check out the Secure Power outlet on SunnyBoy TL type Inverters. Its not the intended purpose, but you can get up to 12amps of 120Vac when the sun is up without needing any batteries. Keep your fridges running during the day and coast through the night with the doors closed. Don't have to intertie with the grid - but you might as well.
How you gonna fend off the neighbors?

[Mike90250]

Welcome.
I'll only address a few of your many questions.

Fridge Compressor Startup.
Generally at least 5x the running wattage of the motor. Using less than a 1,000w inverter will likely fail to start.
Pure Sine wave inverters power motors like they are designed to run, mod sine will have a motor generating 20% extra heat from losses induced by not having a pure sine wave. That heat must be dissipated by the standard cooling coils (the motor is in a sealed can of refrigerant for cooling and lube), so the fridge runs longer & hotter when using mod-sine.

Dehumidifiers use compressors too.

Some appliances are using an "inverter driven compressor" which greatly reduces the starting surge.

Duramax generators. I've heard 300 - 500 hour lifetime. then the engine is toasted.
Look for 1800 rpm gensets for long life

Propane fuel on gensets. 20% reduced power from nameplate. No valve lube from dry propane, so the heads/valves often overheat, Maybe a daily spritz of engine fogging spray will prevent.

Running direct from PV. You will need to oversize PV array to allow for faint wisps of clouds to not totally shut loads down. Panel output drops like a rock, with less than perfect sky's. Voltage stability - panels are in multiples of 18V (18V needed to charge 12V battery) So you are powering 12-15v gear with 18V, need a regulator. You may be able to use a car stereo Farad Capacitor to run a charge controller, but I have no idea how long it will work, neither would be operating normally.

Humidity design your house with the same principals used in the humid regions, large openings, elevated from ground moisture, window overhangs to shade windows to reduce heat loss, large screened porches.

[keepdoing]

Check out the Secure Power outlet on SunnyBoy TL type Inverters. Its not the intended purpose, but you can get up to 12amps of 120Vac when the sun is up without needing any batteries. Keep your fridges running during the day and coast through the night with the doors closed. Don't have to intertie with the grid - but you might as well.
How you gonna fend off the neighbors?

Wow! Dude - you should get a raise They don't pay you enough! LOL You pretty much solved all my problems here. We've got a picky local EMC about grid tie - but they have been moving in this direction, and of course tying to the grid if possible is a no brainer - if they let me.

Only open question I see is that the "Secure Power Supply" seems to only feed 1500W to the designated power outlet. As Mike said, I might want to run an extra Panel or two to overcompensate for little cloud drifts - but do you think that the 1500W would be enough to have both fridge/freezer hooked up unattended at once and not bog out if they were both booting. Does anyone know if the Sunny Boy 4000TL-US, 5000TL or 7000TL have higher designated power outlet built in (than the 1500W?). I couldn't find anything on it.

And to ANSWER some questions.... 1st one is from 1st Responder regarding WHY WOULD I NEED FRIDGE??? Simple... Groceries would indeed be shut down. People gotta eat. It is called a garden, a darn big one, and hunting. It's hard to eat a whole deer at one sitting without it spoiling. Had the crazy notion of freezing some. And yes - I am up to my eyeballs in canning, dryig etc already. I like diversity

In regards to the question on fending of neighbors..... FEED THEM as much as I can. Maybe shoot some. That last little bit is a bit tongue in cheek - depending on how bad it gets, and how unruly things turn. My opinion is that if this indeed comes to pass... the ones that survive will develop communities that support each other. People will learn to give what they can - or be perceived as having too much - and thereby risk having it taken. There won't be any manuals - just common senses, some luck, and being as prepared as you can.

I want to thank you for pointing me in the right direction. I do think this is what I was looking for.

I am curious as to the answer to how much tolerance I need in "direct panel powering" this SunnyBoy Secure Power Supply, and how much 1500W will get me in actual hooked up watts (including start). I think it might get the 2 fridge/freezer setup - any alternative view points? I'd probably have to manually hook/unhook for various power loads during suntime I guess - unless anyone knows of a timer/automatic switcher between load devices I could use to switch hands free.

Peace,
- david

[solarix]

All the SunnyBoy TL inverters whether 3000W or 7700W have the same 1500W spec on the secure outlet.
To do that they need significantly more array than 1500W to handle reduce light conditions and all the losses etc.
If the load exceeds the outlets rating or the array's reduced output (even for an instant) it shuts down until the load goes away. i.e. no surge capability. Could of course use multiple TL inverters - especially with the savings on batteries...
Being grid-tied is obviously way more productive and efficient and worth the trouble, but if a few people in Hurricane Sandy had these TL inverters, it would have revolutionized those neighborhoods.

[SunEagle]

......, but if a few people in Hurricane Sandy had these TL inverters, it would have revolutionized those neighborhoods.

That is if their solar arrays didn't just blow off from the wind or get damaged by flying debris. There was also a lot of clouds which makes electrical production near zero even with the SMA secure outlet.