David Baillie

Jay Angler wrote:I am wondering how many of these strategies got overtaken by "cheap" batteries in just 5 years?

I have heard that many have and that's a shame because Permaculture is all about not putting all our eggs in one basket.

I thought Rosie Barnes from Australia did a video run down on the alternatives and why, at the moment, batteries are winning. The trouble is that batteries don't shift on the timescale of months, rather than just hours or days, and there are many places, like my Island, where we need seasonal storage to truly get off fossil fuels.

I am genuinely hoping that some of the "alternative roof-top wind" systems designed to turn city wind-tunnels into electricity, become viable, because these at least provide energy when the sun isn't shining. This can at least shorten the storage problem, even if they don't eliminate the problem.

Of course, convincing people to "just use less", has its place...

When I crunched all the information available to me my conclusion was the only home scale long term stable, storable, renewable energy source was wood. Whether you stored it as firewood, chuncks of wood for a raw wood gasifier or converted it to charcoal for running engines in a charcoal gasifier the tech is fully developed and affordable.

John Weiland wrote:

Chandrapal Mehula wrote: ....3. Stop at the BMS or inverter low-voltage cutoff, or at about 2.9 to 3.0 V per cell if you are watching individual cells. Don't push below that..

Thanks for all of the excellent and helpful responses.  One question about the statement clipped above:  Won't the BMS automatically stop discharging at the low voltage cutoff? In other words, won't this prohibit me from pushing discharge below that voltage limit even if I wanted to?  Thanks!....

Yes it will but set your inverter low voltage cutoff a little higher Than that to avoid a battery level shutdown.

Kara Ann wrote:Hey T - thanks for your candor and for providing a frame of reference on this.  (And hoping you are enjoying the bacon from your summer Lefty and Righty pigs these days!)

And thanks David - I appreciate the input!  Can you say more about grounding, specifically how that would be implemented with a plug and play unit like my Pecron with its solar panels?

I suppose that if there were a massive CME event that fried all the electronics, we'd all be in a whole different world, and protecting the Pecron unit here on the farm would be one very tiny piece of a huge puzzle to be solved.

And we would still continue to chop wood and carry water and plant seeds and butcher the culls and pick the fruit and store the harvest just like always... and be glad that we were not in the middle of a big city.

the portable unit you listed is what they call a floating neutral unit. Unfortunately the ground usually runs to the battery negative then to a chasis ground screw of some sort. Usually you run a wire to a whole house ground. Even then i don't like the idea of the ground running through my battery negative. If you don't have a whole house ground then you would have to completely disconnect the unit from input and output to protect it.  Grounding your array and the solar input on whole home systems is usually done by using either a bare ground that runs in the conduit or better using steel encased wire generally referred to as Teck cable. The casing and the array ground both go to a whole home ground plate or rod. At the size of the system you are describing disconnection is really your best bet. If I was starting from scratch I would install a ground plate and run my grounds to it.
Cheers,  David

Winter is coming and this topic deserves a bump. Times change, thinking changes but most of the thread holds up well.

Kara Ann wrote:

Ian Sa wrote:
"I recently received the following question regarding EMP effects: “What will happen to vehicles with electronic ignitions, a Chevy with an ignition module, but they are not hooked to a battery, with no path for electricity to follow, can it do damage? There may not be power on the grid, but what about a generator? Can a drill that was not plugged in still be able to run?” ...
The energy from the EMP pulse wave will melt down the transistor ‘junctions’ within semiconductor electronics....
Will your drill stop working? Maybe. Does it have any electronic control in it other than its basic switch and coil winding?
Will your generator work? Maybe. All previous caveats and questions apply… Most all generators have electronic controlling circuits in them.
Also know that electronics are embedded in nearly everything that we use today."

source:
https://modernsurvivalblog.com/emp/will-emp-pulse-fry-anything-electronic-not-plugged-into-the-grid/
---------------------------------------------------
--my reading of the article :
The clippings form the article above imply that coils are not burnt out. Electric generator without electronic controlling circuits in them will work.

Hey Ian and Peeps-who-understand-EMP-implications well,

I am loving my offgrid life with a Pecron E2000LFP, cascade battery and solar panels.  While I have read about spaceweather / grid / electronic implications, the bottom line is that I don't even know how much I don't know about the EMP implications of disruption on my farm due to space weather following a sun coronal burp.

Backwoods Solar has this EMP/CME hardening kit
Any Permies with a good understanding of this who can help me to assess how useful this is actually likely to be? How necessary to plan for?
Please share your wisdom for me and all the other well-intentioned-but-mostly-clueless-on-this peeps here on Permies?
Thanks in advance...

A ferrite kit might work but short of lab level testing you would have no assurance it will work properly and if it does not... Well the whole world is toast so what is a warranty worth? There are things you can do. Install a good lightning arrestor on your solar inputs. Make sure your entire system and array are properly grounded so surges have a place to go. you can use surge protectors for point loads which offer some protection. Metal encased wire runs that are grounded. At the size of your system have a backup on hand and rotate them as needed. The hardcore even go so far as to seal sensitive equipment and spares in a faraday cage when not in use. Personally i could cludge together a working system from spares I've accumulated. Everything I've read says any non powered system disconnected from long runs of wire should be safe.  The problem with EMP and solar flares is you cannot study a real world rollout in a lab and that's about all the testing that has been done. I try to be as honest as I can sorry if there is no sure fire answer.
Cheers,  David Baillie

Mikael Korhonen wrote:Good question! Our all-in delivered cost usually lands around 8-12 cents per kWh, with grid transfer fees and taxes added on top of the spot price. The real win is the cheap overnight hours, where the spot price often drops to near zero and we run the water heater and other heavy loads almost for free.

ive worked it out that with grid fees and taxes I pay an average of 18 cents CAD per kWHr. So 13 cents USD or 0.115 euro... That is supposed to go up soon as they roll back some subsidies. As a solar installer it makes it hard to convince people to install systems based on economics alone. Most of my clients are off grid.
Cheers,   David

bogdan smith wrote:I have an inexpensive inverter with limited functionality. I replaced the stock Wi-Fi logger with a custom one based on an ESP32. We have a preferential (lower) electricity rate at night, and—provided there are no blackouts—I can make efficient use of the system thanks to my 21 kWh battery bank and this smart logger. The custom logger allows for integration with Home Assistant and also enables the control of Tasmota-based devices.

Looks like you've made great progress since last winter. I wish you a warm,safe, outage free winter.
Cheers,    David

Donna Lynn wrote:We bought an electric side by side utility vehicle as a prep for when gas becomes unavailable or just too dang expensive (which looms precariously closer....)  It plugs into a 110 outlet to charge, so I'd be recharging it during peak solar hours.  Or doing laundry, running a canner on an electric burner, vacuuming, using power tools, recharging the electric mower and chain saw, running the freeze dryer or dehydrator, baking stuff in the electric oven, using the infrared sauna, and so on.  

Although an actual solar sink to hold power would be something more along the lines of pumping water into a high tank or uphill pond to release later as needed to run a hydroelectric unit.  Or the compressed air others mentioned.  We bought undamaged Tesla car batteries from wrecked cars to store power, but they only hold so much, just like any other batteries.  So they can cover us for a cloudy day or two, but that's about it.  

hi donna, what is the model of the electric side by side?

John Weiland wrote:Thanks, David!   Can you tell me why this is not done routinely for LiFePO4 batteries?  Granted, a bluetooth version would be able to give you an estimate based on the battery management system display, but wouldn't one want to be able to 'real-world' test that capacity.  And even if the discharge curve for Li is flatter than that for legacy lead-acid tech, if one was detecting a 'fully discharged' status well before the amp-hour rating on the battery, this would indicate where power deficiencies may be located.  Finally, it seems from some videos out there that comparing LiFePO4 battery specs often involves validating the advertised Ah rating and so this often is done, albeit with shop electrical control units that appear more expensive and sophisticated than I wanted to deal with. Thanks for insights here....

John Weiland wrote:Thanks, David!   Can you tell me why this is not done routinely for LiFePO4 batteries?  Granted, a bluetooth version would be able to give you an estimate based on the battery management system display, but wouldn't one want to be able to 'real-world' test that capacity.  And even if the discharge curve for Li is flatter than that for legacy lead-acid tech, if one was detecting a 'fully discharged' status well before the amp-hour rating on the battery, this would indicate where power deficiencies may be located.  Finally, it seems from some videos out there that comparing LiFePO4 battery specs often involves validating the advertised Ah rating and so this often is done, albeit with shop electrical control units that appear more expensive and sophisticated than I wanted to deal with. Thanks for insights here....

Mart totally wins for geek wizardry! His own monitoring! If I want to test a lithium it depends in the quality of the inverter and the batteries. Those drop in replacements that dont need comms to inverter you would have to charge until it does not take charge, apply a known load and discharge till it shuts down; i dont like that. If its a solark, lux or eg4 ( rebadged lux) and a battery that does two way comms you have a state of charge meter and an app so its way easier. I can apply a known charge to it add in the system running load and watch the percentage go down. If it matches spec you are golden as it ages I would expect it to drop more rapidly. The batteries im installing today are less than 2 years and so far no change over about 12 systems. Here is a screen shot of the lux app: the website version is better. Eg4 and solark have similar ones. The cheaper  inverters not so great I dont install them as its too much call backs and confusing menus. There are other good ones of course.