Making Electrical Power, Small Scale.

[Clay Pigeon]

Some folks just argue for the sake of it...

Power on a small scale. I have not devoted a lot to this but we have had a few fairly decent battery inverted back ups.
Friends own a serious recovery/salvage operation near us. There was a time when folks were scrapping out the family Winnebago as apposed to putting new tires and brakes on it. The yard had about 6 of these come in close together to be salvaged. 4 had less than 40K on the clocks but had been sitting. The inverters were there as were the control panels. We stripped these out. Battery inverted power supply's were not new to me as we had a few race trailers wit them in place. These inverters were serious enough pieces.

I built the 1st one with 8 batterys (a mix of lead acid offerings from the yard) that all checked good. (2) 4 battery bass boat smart chargers and a good structure to house all the parts and pieces we had a fairly "OK" battery back up mainly for lighting. Never tried to run a refrigerator on this one. No fancy in house secondary wiring for this just ample well made extension cords. A good friend talked me out of it and put it in his hunting cabin. This was 12 years or so ago. He swapped out the battery's for deep cycle marine pieces and it has served him well.

I built another one just like it for a good friend and he still has it. Yes they have to run the genny's to bank up the power but not as often as you might think.

The last one was a 10 battery (deep cycle gel) with the last 2 inverters. Had it in place for a few years and never needed it. We did run the lights and refrigerators on it occasionally. It was sold to another friend. He has integrated it into his off the grid solar system.

No magic engineering just solid build techniques. Every wire was crimped and then soldered. I am not certified. I have lost track of the wiring I have done in racing applications with never a failure. Proper tools/materials.

No idea how efficient those systems were. All I know is they worked. and still do. Now we have way more generator/fuel reserves we need to run both property's for a given time period.

I've done and still run a few DC power systems in my life. My sailboat has 500 watts of solar and a 400 watt wind turbine that gives me an abundance of DC power and if its cloudy and windless for a few days I can fire up that Yanmar and run the 100 amp Balmar to charge the house bank back up.
If one wants truly copper wire that tends not to turn green you should buy wire thats tinned to begin with.
I also have a wind system at the farm that runs off an Aeromotor windmill. I can pump water and generate power with it.
It ain't rocket science..

 

[JeepHammer]

Since the conversation took off on right angle tangents and smacked the guardrail of confusion at full throttle,
Electrical Resistance didn't get covered.

I find the above image amusing while explaining something.

Resistance can pop up anywhere in a circuit.
Wire can corrode inside the insulation, corrosion is resistance.

Crimp connectors don't make 100% contact with the wire conductor, mostly because the average guy is going to be using stranded wire, and there will be air gaps between strands (without solder) and that will be Resistance to the current flow.

Particularly when working with DC, the terminals on equipment are often grossly undersized for 100% duty cycle, there simply isn't enough contact surface area for 100% transmission of current, which creates resistance to current flow.

You will encounter dissimilar metals, copper to steel or aluminum, and these changes in conductor create Resistance to current flow.

You will never have zero Resistance, but minimizing it when/where you can will significantly increase efficiency.
This is particularly true when dealing with the biggest currents, which will always be around the batteries.

 

[churchmouse]

I've done and still run a few DC power systems in my life. My sailboat has 500 watts of solar and a 400 watt wind turbine that gives me an abundance of DC power and if its cloudy and windless for a few days I can fire up that Yanmar and run the 100 amp Balmar to charge the house bank back up.
If one wants truly copper wire that tends not to turn green you should buy wire thats tinned to begin with.
I also have a wind system at the farm that runs off an Aeromotor windmill. I can pump water and generate power with it.
It ain't rocket science..

Keeping it simple.

The solar my buddy used my inverter bank on is pretty complex. I understand it. But man he spent some coin on it.

 

[miguel]

Do the guys in the video get paid extra for having to ride the helicopter?

 

[JeepHammer]

Understanding wiring and properly sizing of same I always make sure to use what is needed. Not the minimum either. On my battery racks I used welders drop cable to string the battery's together. And yes, stripping out the system in total was a huge advantage. The inverter taps were in the middle of the battery string. I have seen golf carts and fork lift systems done that way. Seemed to make sense.

We live Urban. The grid has been reliable for the most part. Even with that we have 4 gennys fueled ran and at the ready.

Notice in the diagram I posted that even parallel strings are tapped at opposite ends for inverter & charging.

Center caps are better than same end taps!

What I found by direct testing/observation aligns directly with electrical theory, current seeks the path of least resistance.
When both taps are at the same end, the first battery gets charged/discharged more, second back is second most, etc.
The last battery in the string is chronically undercharged and damaged.

When I builds cables, it's for the MAXIMUM potential load, plus 10% safety margin & to overcome potential resistance losses.
Whatever the maximum load of the inverter is, plus 10% safety margin.
Or what ever the load (well pump or whatever), plus 10% safety margin.

The grid certainly isn't reliable 17 miles out from a 'Secondary Market' town I'm nearest to.
The grid failed during the artic blast two weeks ago AGAIN!
It's on and off about once a month out here, and it's a roll of the dice when it comes back on...

I have found the old 1903 Brown & Sharp chart is about dead on for everything I've done.
I use infrared to diagnose resistance line & connection losses, and it's been dead 100% of the time when using pure copper conductors.
A common thermal gun ($20 at parts stores) will find major issues for the most inexperienced user. When the temp goes up, there is a problem, can't be more simple than that...

One of my go to things with DC/cables is surface contact area on ring terminals/studs.
The studs, and sometimes the ring terminals are too thin & narrow to conduct the current.
My quick fix is a '82 or older penny, bronze, 95% copper.
Solder it to a brass nut and screw it to the stud, then add the ring terminals and the second nut.
Keep in mind I don't do this unless the terminal heats during operation indicating a restriction...

If needed I solder a second penny in the ring terminal increasing the contact surface area to the width of a penny.
Those flattened tubing pigs are the worst offenders, and I don't always want to change the lug right there, right then.
1 or 2 cents, a drill, some solder & 'Jet Torch' cigarette lighter... Off to the races! A field fix that isn't difficult.

Things like winch motors & power solenoids need bigger stud terminals and there is simply no way to change them.
It's often they are steel instead of brass or copper, which also upsets me,why make a DC electrical component with copper contacts, but steel connection studs? Schizophrenic...

When we build the off road engines, it always puzzles the guys when I silver solder an old silver quarter (with drilled hole) over a threaded hole somewhere near the starter motor.
That old silver quarter is a 100% reliable contact patch for the engine negative contact, no questions asked, and it will be there and still working at 100% after 40 years of sloshing through salt, the block rusting, the bolt rusting, being doused in water 10,000 times, etc.
I got so tired of ignitions & starters cooking themselves when the block connection corroded, it was the most simple idea but it's 100% bullet proof since the block doesn't corrode/rust where the cable meets it.

I won't buy a steel terminal starter relay, older Jeeps having a Ford relay on the inner fender.
Simply no point in installing something that rusts/corrodes, and if you off road, you KNOW it's going to fail in the worst possible place/time.
When I do the expedition treatment to a Jeep, I install two relays in parallel with LED indicators to let you know when one fails.
You probably won't know it failed until you do maintenance, and there isn't any reason to 'Carry A Spare' when it can be installed directly for redundancy.

If you work on old Jeeps, you know that 'Spares' thing is mandatory unless you like LONG 'nature' walks for replacement parts....
AMC/Jeep... A Mixture of Cars / Just Empty Every Pocket is what AMC/Jeep stands for!

When it comes to small power, expansion room needs to be planned for, no one gets it right when they build the first time...
No matter what you *Think*, you will want more electrical devices, so expansion room is a REAL good idea.
Add in a woman, and that expands by a factor of 4.

I USUALLY try out new panels, hang them on a new battery string for expansion.
It's about 1:1 for newer high output panels on 6 Volt batteries, but the older, or lower output panels you will need 1-1/2 or 2 panels per battery.
I try NOT to grossly oversize production to battery storage capacity, but the panels will have to be slightly higher output than the batteries they are charging.
The excess POTENTIAL hits the inverter, and if the inverter doesn't use it, it's just wasted potential.

Since I'm off grid, the batteries have to nominally reach 100% charge every day, even in winter.
This excepts overcast days when the batteries simply never get 100% charge.
Extra battery strings provide more reserve power, share the load between strings en banc, so a single string doesn't have to do all the work.
I heat with gas, so in the winter we actually use less power than in summer, and in summer the panels produce MUCH more, so the extra usage is provided for by nature.

I'm a little better off than some, when I fire up the generator/welder in the shop for 220 3phase AC, that generator runs everything.
Well pumps top off the water tanks, the batteries get charged, etc.
No sense in wasting the excess power potential that generator makes, might as well get the most from the fuel I'm burning...

It's a balance, and so far it's in my favor, but that was before the idiotic tariffs...

 

[caverjamie]

It all sounds complicated. I'm set up pretty simple, flashlights and two good ole generators. I have a diesel 10kw mep-803a (military surplus) and my little 1.8kw Honda eu2200i. The honda is way more fuel efficient and can run the heat (outdoor wood furnace) which is all I'm really worried about. The mep can run everything I could ever want, all at the same time, and could drink me dry doing it. It's kind of a toy, but hey I can run the central AC in the summertime if I want. We never lose power here though...

 

[churchmouse]

It all sounds complicated. I'm set up pretty simple, flashlights and two good ole generators. I have a diesel 10kw mep-803a (military surplus) and my little 1.8kw Honda eu2200i. The honda is way more fuel efficient and can run the heat (outdoor wood furnace) which is all I'm really worried about. The mep can run everything I could ever want, all at the same time, and could drink me dry doing it. It's kind of a toy, but hey I can run the central AC in the summertime if I want. We never lose power here though...

We have lost power maybe 3 times since I sold the battery backup but never long enough to get the gennys out and string cords.
I have a list of things to do and upgrading this is 1 of then. A way to plug the mobile Gennys into the house's and the shop and have them secured. I have a plan...

 

[ditcherman]

I do all my own stunts.
Started out out of necessity. Breakdowns at the hog barn, grain system leave no time for a call. Did my own house when we gutted it and remodeled, done a few others since.
Wondering what all you smart guys think about this book...
ref=dp-kindle-redirect
"There Are No Electrons: Electronics for Earthlings, by Kenn Amdahl
It's a really funny read that can help someone understand some of the concepts. It may all be wrong as well, I don't know.

 

[churchmouse]

Due to this discussion I have been looking at putting outside genny access to the main panels. It will not be all that hard I just need to gather the proper materials and get it done.

 

[foszoe]

Interesting discussion. Motivation to do this is growing.

Don't mind JK, he just destined to do what he does.

 

[JeepHammer]

Due to this discussion I have been looking at putting outside genny access to the main panels. It will not be all that hard I just need to gather the proper materials and get it done.

Depends on scale.
If you intend to use a small gas generator, I'm not sure detached (remote) is necessary, but you are the best to determine that.
A good exhaust vent would be mandatory, and I would use a hand pump to fuel instead of trying to dump fuel into a hot and/or running generator...

Mr. Murphy visits me regularly, and in the rural area I live, we are always the last to get power back when something fails.
I was still running a single string of 6 Volt batteries & a large steel case industrial battery when a big storm with straight line winds hit us on Friday night.
Me & the wife watched the big blow happen & went to bed, worked all day on Saturday, got up on Sunday and decided to have brunch at the local bait shop/diner about 1-1/2 miles away...
Closed due to lack of power.
Talked to the people coming from church, power out for at least a couple miles around, people complaining about freezers thawing, no hot water, etc.

We took the generator around, lent another generator out that got passed around, took 5 days to get power back.

We didn't even know the power had failed for 36 hours...

When we lived in town, about once a month some drunk hit a pole, someone threw the wrong switch at a substation, lightening hit a transformer, a squirrel got into a transformer about once a month, and that wasn't counting the fails from the power suppliers that blacked the whole town out.
No big deal most times, an hour waiting for public utilities to get there and replace short circuit/lightening protection and back up and running, just annoying when you are trying to get something done.
In small towns a blackout from a squirrel or antique substation equipment makes the newspaper, so a day later we found out what happened...

Make no mistake, there is a learning curve, and there is time invested in inspection/repairs!
Battery maintenance, battery rotation in the strings, keeping track of generation and usage to determine efficiency, but I consider it a 'Hobby' rather than a chore.
I'm often trying to figure out ways to make things more efficient, less losses, safer system, more streamline.
I guess it's better than drugs, porn or 'Social Media' addiction, or more productive that my firearms & antique junk addiction...

The biggest issue I have to deal with is a catastrophic fire in my utilities building.
A shipping container set down over the well head (so some idiot with a bush-hog doesn't hit the well head anymore!),
Battery banks, power inverter, well/pump, water tanks and the smaller back up generator are in there.
Water & power... A fire would be REALLY bad...

Metal enclosure, Earth sheltered (domed) over the container helps with lightening issues, insulated walls outside so metal walls inside helps limit damage, and I try to keep combustibles out, but there are batteries and there is a propane line for the generator...
Since the pressure tanks for well water are in there I have automatic sprinklers, the only protection, but electrical & water don't get along very well, and the potential for so much battery power will long outlive the water reserves in the tanks.

With DC, there is no 'Fail Safe' Earth Ground to save you...
When you see vinyl (shiny) 'Battery' cable insulation catch fire and burn furiously in a couple seconds you will switch to something like welding cable pretty quick where you can!
I'm becoming a big fan of metal conduit also, having to teach myself how to bend & attach the conduit I'm slow about the refit.
I learned everything 'Seat Of Pants' so I still have quite a bit of PVC conduit.

One thing about Earth sheltered battery banks, the batteries stay at reasonable temperatures.
Frozen or overheated batteries don't live long, and even though there is a grassy 'Bump' in the yard, the batteries are much happier.
A metal container in summer routinely reached 140*F inside, and the batteries didn't much care for that.
Much happier at reasonably constant temp and well vented now....

Just some ideas for those of you motivated... If not, we'll leave a light on for you!

 

[JeepHammer]

Not sure the thread torpedos have lost interest, but I'll try again...

If you rely on gas generator, then you will probably be just plugging things in, which is easy.

If you want to make & store your energy, that means batteries (or more exotic super capacitors).

With batteries, you MUST make a battery cable that will supply the largest device you own,
I make my own, and after two decades of off grid power, I've leaned how to make cables that survive for decades.

Here is a picture of a group of terminals, crimper & cable cutter...

Terminals (large size called 'Lugs'), come in many shapes & sizes, many materials, but when working with big battery power you must remember anything bare copper the batteries are going to corrode/eat alive really quickly!
The flattened tubing on left will die the quickest, the flattened end leaves a space for acid to crawl right up the terminal to the wire.
The others here are 'Blind Socket', they have a solid disconnect between battery contact & wire.

When corrosion creeps, the wire/terminal suffer, build resistance, and you loose your production/efficiency to resistance.
Corrosion can be ANYWHERE, even inside the insulation. This cable was *Supposed* to handle 150 amps, but wouldn't pass 30 amps without heating way up due to corrosion inside the insulation.

Corrosion is the enemy, so anything & everything you can do to stop corrosion will extend the life of your cables, the good part is since industrial applications use a lot of batteries there are common products to do this.

I prefer welding cable over generic 'Battery' cable,
1. Better Insulation. Common welding cable comes with high temp, abrasion resistant, chemical resistant insulation.
2. Finer Strands, easier to work with/bend, carries more amp capacity for any given size.
3. Pure, virgin copper. The primary function of WELDING cable is to deliver amperage, and virgin copper does that best.

I start with a hard mechanical crimp on the connectors. There are other types of connectors, but when set up with a crimper, this is the fastest, most reliable way I've found.
Notice the copper wire is exposed even after a good crimp. Something has to be done about this...

*IF* you are sharp, you noticed these battery post terminals are two different sizes.
Positive will always be larger than Negative.
Many batteries have threaded studs, which are sometimes different sizes, see the terminals above for stud terminals and stacking terminals.

If you look further down in the posts, you will notice the Positive terminals are all marked with Red heat shrink, all Negative are marked with Black heat shrink.

 

[JeepHammer]

For me, the next step is Silver Bearing Electrical Solder.
There is a BIG difference between structural Silver Solder (expensive & takes HIGH heat), and 'Plumbers' solder which almost always has acid core.
NEVER use acid core solder, or acid cleaner/flux on electrical connection!

I use Silver Bearing (2% to 4% Silver typically) ELECTRICAL Solder works fine for decades when done correctly...

Solder the connections to seal up the air spaces, and 'Tin' (solder coat) the exposed copper wire...

Once the silver bearing solder is in place, I seal up the connection even more...
I use INDUSTRIAL Heat Shrink Tubing, the industrial stuff has GLUE on the inside, and that stuff seals like crazy!
(Takes a low yield nuclear blast to get it off!)

Heat Shrink in place, heat from soldering terminals already starting to shrink it down..

Notice the glue welling up and sealing up the connection here?

What's not shown....
You always want to leave 4-5 inches extra in your cables. Terminal ends will ever tually need to be replaced with lead acid batteries no matter how well you maintain them, leave a little extra length so you can reuse the copper cable over again.

Have a damaged spot on the insulation someplace? Need extra insulation some place it rubs on something,
Slip heat shrink over the smaller terminals and shrink it down in place. Works great!

 

[JeepHammer]

*IF* you have more than a couple batteries, you will eventually want to move things around.
You will probably want 'Disconnects' so you don't have to bolt/unbolt things....

If you have battery strings feeding a larger inverter, you will want a positive disconnect between batteries & inverter so you can do wiring or work on the system.

I use high Amperage 'Anderson' connectors, from very small to 350 Amps (plus) for economy, absolutely positive QUICK disconnects.
I use these on my farm equipment so I can switch one battery around where needed, saving $100+ on each piece of equipment,
I use these on my Jeeps so I can pull a battery & use it for camp or tool power, lend power (with jumper cables) to someone in need.
I use the jumper cables with a 'Y' (series) yoke so I can weld off the Jeep batteries...

Anderson connectors, search eBay for "Anderson Connectors"....

175 Amps on left, 350 Amps on right.
These haven't been soldered or heat shrinked yet...

Anderson connectors also have anti-corrosion boots that keep water out along with caps.
I fill the boots with dielectric grease before install to further seal up against corrosion.
Where grease is, water can't enter...

This shows the completed Anderson connector with boot full of dielectric grease & a quick pull disconnect handle.
Notice even the holes in the connector allow accessors & solid mounting...

 

[JeepHammer]

BAD TERMINALS!

These are 'Pre Made' cables, and if you have a good look,
Notice the terminals are aluminum, not copper?
Notice the holes punched in the terminals from the crimping process allowing acid/moisture to directly enter the terminal/cable...
Notice the vinyl heat shrink that's just (not very good) insulation and doesn't seal the connection up.

This is why I tell people to NEVER buy pre-made "Battery" cables!
These cables came with a cheaper (China) inverter,
Too small gauge for the inverter, alloy wire, lousy terminals, etc.

 

[JeepHammer]

Well, forum isn't going to let me post diagrams...

 

[Clay Pigeon]

Well, forum isn't going to let me post diagrams...

So you torpedoed yourself..

Grandpa said, you gotta be smarter than what you are working on.

 

[churchmouse]

Good post/pics on the terminals. The grey plug ins are well known to us. We have used them om the race cars and battery banks for years.

I have looked at and changed my mind a few times on how to do the remote genny's. My shop sits between the 2 houses I will be powering with the genney's. We have the exhaust thing figured out pretty well and noise is dealt with efficiently. Putting together proper power cables is key. Making it "Female" friendly is another factor. The woman folk are smart enough but it still needs to be as simple as I can make it.

We are upgrading the panel on the daughters place next door so that will be fairly simple too integrate. My house a bit more complex due to add on's that have the meter base inside.

 

[ditcherman]

Thanks for this, a lot of good info here.
I always wondered why battery connectors weren't just made of good old copper. I guess it wouldn't actually be good. Now I wonder why they can't make a battery that doesn't 'leak', if that's what is actually happening.

 

[churchmouse]

Thanks for this, a lot of good info here.
I always wondered why battery connectors weren't just made of good old copper. I guess it wouldn't actually be good. Now I wonder why they can't make a battery that doesn't 'leak', if that's what is actually happening.

Never had an issue with the new battery's.