Making Electrical Power, Small Scale.

[JeepHammer]

Electrical Anything is 'FM' to most people simply because they never learned how it works and can't see it work.
('FM' = Freakin' Magic)

The second big road block is basic math.
While a solar powered canculator makes this dirt simple, people simply refuse to do it.
i don't know if the 'Preppers' are the low end of the educational process, or if people with math phobias are drawn to 'Prepping', but it's the hardest part to overcome I've found.

Here are some basic fundamentals to get you started...

1. Everything you do will be broken down into a standard unit of electrical measure, WATTS.
It doesn't matter if it's AC (Alternating Current),
Or if it's DC (Direct Current),
Or if you are talking Volts (Pressure),
Or talking Amps (Volume),
EVERYTHING will need broken into WATTS when you buy or build your system.

Watts = Volts X Amps.
Or,
Volts X Amps = Watts.

Example,
1,500 Watt hair dryer (or microwave, or space heater, etc)
1,500 Watts devided by 110 Volt outlet power...
1,500 devided by 110 = 13.636 Amps.

That same hair dryer at 240 Volts (most of the rest of the world)
1,500 devided by 240 = 6.25 Amps

That same 1,500 Watt load on a 12 Volt system,
1,500 devided by 12 = 125 Amps

All EXACTLY the same 1,500 power LOAD (draw on power), but three different Voltages mean three different Amperage loads on supply.

This is EXACTLY what you will need to know how to do to size your system, stupid simple math, and yet very few will get past this part.

 

[Clay Pigeon]

They call it OHMs Law, E over I = R

 

[JeepHammer]

2. The two most common electrical current types you will deal with are Alternating Current (like household current),
And,
Direct current, like from a battery or other storage device.

The two ARE NOT compatible!

The production from an 'Alternator' (Alternating Current Generator) has to be 'Rectified' into Direct Current before you can store it in a battery.

That stored DC energy has to be 'Inverted' into AC before normal home appliances can use it.

Virtually all vehicle 'Alternators' have a Rectifier built into them, but in an emergency, it's good to have a couple extras around (about $15 each for most common car alternators, or you can reclaim extras from existing alternators).

You won't get a vehicle alternator to directly power AC appliances most times because of winding differences and rotor speed differences, so converting to D.C. and either using D.C. Directly,
Or inverting to AC is the most simple & economical option.

There are some things you can do with the AC directly produced by a vehicle alternator, but it's quite limited.

 

[JeepHammer]

3. There is an ENOURMOUS amount of power concentrated in a battery!
Never under estimate that!

Welding steel (stick welding) can EASILY be done off two car batteries.
Welders normally produce 18-22 Volts, two batteries gives you 24 Volts.
Welders normally produce around 60-80 amps to burn common wlxing
rods, two batteries can provide up to 1,000 amps.

If you don't think welding steel is a priority, low consumption lights (LEDs) and computer fans can provide light & ventilation FOR DAYS from a single car battery.

If you still aren't on board, two batteries & a common winch can lift up to 4 Tons at a time, and that's a stuck vehicle moved or heavy roof for a shelter set the not place...

If you mismanage that enourmous potential power, it can do GREAT HARM, including killing you and burning down anything around it...
It's not quite dynamite in power compairison, but it will do so much more FOR YOU than dynamite will.

 

[JeepHammer]

4. It takes MOVEMENT to produce electrical power...
Moving photons (light) hitting solar panels,
Moving water to power a water wheel,
Moving wind to turn a wind generator...

Photovoltaic (PV) are sold state, no moving parts, but take up space to make any significant amount of power.
Wind MUST have clean airflow to work, and wind generators can be seen quite a ways off.
Moving water is often the most reliable, but production will depend entirely on how much moving water you have.

None of the above take a lot of lubrication oils, fuels, spare parts for an engine, ignition system, fuel system, cooling system, etc.
and all three make a LOT less noise than a generator...
This can be a security issue, so asses what you have and move from there.

 

[JeepHammer]

Once you have made the assessment, then start collecting what you need.
Everyone will need actual Deep Cycle batteries, the most economical source currently is 'Golf Cart' type Deep Cycle batteries.

A note here,
If you can find Steel Case (fork truck) type batteries, they are GREAT, but difficult to move.
The amp-hour rating is off the charts compacted to golf cart batteries, but those amp-hours will come at a premium cost to you when purchased new...

If you pick a car alternator based generator, then find some cores that are alike, and also buy perminant magnet rotors RIGHT NOW.
This is the one part that increases efficiency the most & simply won't b available after a major disaster.
I would also look into blade or water wheel hubs that mount directly to the alternator shaft.
These are usually heavy gauge sheetmetal and while you can cobble something together, the purpose built units aren't too expensive and work GREAT.

My small wind-gen projects simply use PVC pipe (cut long ways) for blades, while larger units will need a fabricated blade.

Two other things,
Some rolls of home wiring to transmit AC current, and welding cable with terminal ends for DC current/battery cables.

The stuff sold as 'Battery Cable' sucks rocks and you will quickly find it next to useless. If it has a shiny vinyl insulation, and the interior strands are VERY small & tightly packed, you are going to have no end of problems with it...
Welding cable with a UV resistant insulation and very small, tightly packed strands will serve you MUCH better for years to come.
Inscrewed around with 'Battery Cable' for about 2 years before I learned my lesson...

With solar panels, you will need more initial cost investment since you will
have to buy panels ahead of time...

If you have the resources, nothing says you can't have all three combined at the batteries. When it's cloudy, the wind is usually blowing enough I get a little production from my wind generator...
If a water source trickles in summer, the sun is usually shining brightly and for many hours in summer...
Combos are fine, even recommended if you have the resources!

 

[JeepHammer]

This is going to blow up the brains of the 'Electrical Engineer' types, of the radio types...

Direct Current (DC) DOES NOT have a 'Ground'.
There is a Positive Conductor, and a NEGATIVE Conductor, these 'Conductors' MUST complete a 'Circuit'.

A 'Circuit' starts & stops at the same point,
A battery, a generator, a solar panel, etc.,
But they MUST complete a closed 'Loop' or 'Circuit' to work.

---------

Now, to save the arguments coming, there can be a Positive or Negative 'Buss', a multiple connection point that's a common pathway back to the source positive or Negative to complete the circuit.
Some electrical disciplines refer to these as 'Chassis Ground's, which is a misnomer at best, and at worst confuses the basic, simple circuits I'm trying to describe, so it's counter productive to discuss or refer to these without advanced education to know specifically when/where these apply.

---------

A 'Load' is an electrical appliance, it's an intended drain on energy resources.

The Circuit MUST move through conductors to switches, controls and Loads to do work,
Then the circuit MUST he connected back to generation/source by conductors.
This completes the circuit, a full 'Lap' between source through devices/loads and back to the source.

Your device simply won't work without completion of this closed circuit.

---------

Example, TWO wires (conductors) from generator to battery closes the circuit, and batteries charge.

TWO wires from batteries to working Load (lights, motors, inverters/converters, etc) completes the Circuit and makes the working Load actually WORK.

If you don't know the specifics, both Conductors (wires) should be the same size (called 'Gauge', as in American Wire Gauge).
The size of the conductors will change as the Load (in Amps) changes between different devices.

For instance, off the same battery in a vehicle, a larger Conductor set is used for the starter motor, which requires more Amps to work, than a light bulb will require, since light bulbs require less Amps to operate.



This is the Brown & Sharp Scale for DC current.
Look at the Amps your load will require to work properly, then move to the left column to determine conductor size in AWG (American Wire Gauge).
This chart is for a 100%, full time duty cycle without starving the device or hearing up the wiring.
I've found this scale to be 100% accurate in every case, and it meets 100% of common electrical codes for conductor sizing.

This is often the big missing link for the do it yourself type failures, they get charts showing 'Automotive' sizing, which isn't 100% duty cycle and there isn't any nationally recognized standards for 'Automotive' charts.

This will keep you from burning up devices/loads and/or cooking the wiring...

----------

Amp load DOES NOT Care what the Voltage is!

*IF* we go back to simple math it's easy to break down the load into Watts, Volts & Amps.
A 1,500 Watt blow dryer at 110 VAC for example,
1,500 Watts ÷ by 110 volts = 13.63 Amps.
Consulting the chart above, that device needs a 14 AWG minium sized set of conductors to operate at 100% duty cycle.

*IF* that same 1,500 Watt blow dryer was ran off a 12 VDC source...
1,500 Watts ÷ 12 Volts = 125 Amps!
Consulting the chart above, that's a whopping 2 AWG minimum sized set of conductors!
(The smaller the number, the larger the conductor, and 2 AWG is REALLY big!)

There is a reason energy grids, and many off grid systems, drive the voltage UP to transmit the same Watts through smaller conductors.
Copper isn't cheap, big copper is big money.

 

[JettaKnight]

This is going to blow up the brains of the 'Electrical Engineer' types, of the radio types...

Direct Current (DC) DOES NOT have a 'Ground'.
There is a Positive Conductor, and a NEGATIVE Conductor, these 'Conductors' MUST complete a 'Circuit'.

Not exactly sure why my head should be blowing up...

"Ground", even with AC, is merely a practical implementation, not a scientific foundation or concept.

 

[JeepHammer]

Practical Considerations,

Since big copper is big money...
And since DC doesn't push through conductors nearly as easily as AC does, it's an electrical resistance per foot of conductor (see scale for resistance per foot of conductor when using DC), it's MUCH easier to push AC through long runs of conductor.

So, keeping those facts in mind,
I find it most efficient to push AC through longer runs of wire,
Keeping the output from AC generators in AC form until it gets to batteries, then using a Rectifier to convert to DC at the batteries.
This is easy, simply remove the Rectifier from the Alternator and place it next to batteries.
Production in AC stays AC through the longer run of wire, then gets converted to DC near the batteries.

This keeps large DC conductors SHORT so it's BOTH less copper, and less wire resistance losses.
Smaller wire size for AC, heavier wires at the DC/battery side of the circuit.

When I run the power to the home, I convert to AC via an inverter.
There is a fairly long run between 'Power House' (location of batteries) and my home, I simply run the inverter next to the batteries and run AC to the home.
This let's meet run the home on AC power, just like anyone elses does.

This also keeps solar panels, wind generator, and potential issues with batteries OUT of the house.
Explosive gasses, corrosives gasses, potential for disaster is all kept away from the home.

If you had very small scale, panels or wind generator on roof of home, batteries inside, this wouldn't be as much of an issue.
The issues with batteries is very real, the larger the batteries the bigger the issue/danger. Keep this in mind when considering your own power system...

 

[JeepHammer]

Making Electrical Connections.

'Crimp' terminals are NOT electrical connections!
The 'Crimp' is a MECHANICAL connection, it simply smashed the wire in a terminal, there is no guarantee of an electrical connection, or how much resistance that connection will have.
Crimp connectors are corrosion producers simply because it's two dissimilar metals in contact with oxygen/moisture present.
It's not a question of *IF* the connection will produce excessive resistance/failure, but when it fails and how much energy is it going to waste before total failure.

A PROPER electrical connection DOES NOT produce resistance to the electrical current trying to pass through it...

To this end, the easiest & most common way to ENSURE a proper electrical connection is Electrical Silver Bearing Solder.
This is usually between 2% & 4% Silver in electrical solder that melts at common solder temperatures.

The third part of this beyond mechanical & electrical connections is protection.

Silver bearing solder allows you to 'Tin' (clad or 'Plate') exposed copper so it doesn't corrode.
This also works with exposed copper terminals, heating & 'Tinning' them makes them last longer.

-------

I can unequivocally recommend environmentally protecting the connections, with grease or coatings on exposed terminals, and by using industrial heat shrink tubing on wire/terminal connections.

Industral heat shrink has a glue inside that seals up the connection, rather than just electrically insulating it.
Good copper terminals & copper wire costs big money, and the better you seal/protect them the less they fail or waste your production because of resistance before complete failure.
Silver bearing solder, dielectric grease, corrosion preventing sealers & heat shrink tubing are cheap compaired to replacing terminals & wires/cables often.

 

[JeepHammer]

They call it OHMs Law, E over I = R

Without symbols, it's much easier to teach simply saying Watts, Volts & Amps.

Not exactly sure why my head should be blowing up...

"Ground", even with AC, is merely a practical implementation, not a scientific foundation or concept.

There are people that want to get bogged down in semantics, or argue one specific application that has nothing to do with the subject at hand.

An Earth Ground sure has a specific application when installing lightening protection!
I think Ben Franklin figured that one out for us!

 

[JettaKnight]

I find it most efficient to push AC through longer runs of wire,
...
This keeps large DC conductors SHORT so it's BOTH less copper, and less wire resistance losses.
Smaller wire size for AC, heavier wires at the DC/battery side of the circuit.

That's just absolutely false.


Skin effect, inductive impedance, and stray capacitance all combine to make AC electrical transmission more inefficient that DC. The higher the frequency, the worse it is.

 

[JettaKnight]

Making Electrical Connections.

'Crimp' terminals are NOT electrical connections!
The 'Crimp' is a MECHANICAL connection, it simply smashed the wire in a terminal, there is no guarantee of an electrical connection, or how much resistance that connection will have.
Crimp connectors are corrosion producers simply because it's two dissimilar metals in contact with oxygen/moisture present.
It's not a question of *IF* the connection will produce excessive resistance/failure, but when it fails and how much energy is it going to waste before total failure.

If that's true, someone needs to tell the electrical companies, linemen, automotive engineers, NASA, electrical equipment manufacturers...

A PROPER electrical connection DOES NOT produce resistance to the electrical current trying to pass through it...

To this end, the easiest & most common way to ENSURE a proper electrical connection is Electrical Silver Bearing Solder.

To say it's "most common" is a really big stretch.

Other than electrical circuit boards or solder cup terminals, very, very little is soldered. There's plenty of good corrosion resistant methods of termination and connection that don't involve soldering. Plus, you ever try soldering two wires butted together? It's a PITA and is very fragile. I only do it in a pinch when space is limited and I don't have butt crimps.

 

[JettaKnight]

There are people that want to get bogged down in semantics, or argue one specific application that has nothing to do with the subject at hand.

If you're going to write what appears to be a article about electric theory and practice, then you'd better get the details right. Maybe some folks here think this is very helpful, and hopefully they let you know; it's always good when folks like you share their experiences and knowledge. But as you're writing from a position of a subject (pseudo)expert, I'm going to interject when your facts are wrong.

An Earth Ground sure has a specific application when installing lightening protection!
I think Ben Franklin figured that one out for us!

Apples and oranges.

 

[JeepHammer]

An Example For Practical Use,

*IF* I were starting over from scratch,
AND,
I were 'Mobile' (vehicle transported),
I would use batteries that WERE NOT damaged by deep cycling.

The 'Ideal' battery is probably Lithium-Ion or Lithium-Iron batteries.
These are pretty had to find in the larger sizes, but worth the effort.
These are MUCH safer, don't spill, don't need distilled water, and don't produce explosive gasses.
These also can be discharged to 80%+ of capacity and still recover just fine.
They are also MUCH lighter weight per amp/hour capacity.

The down side is different charging requirements.
There are little charge controllers that are as cheap as $5 per battery/battery set, so it's not a huge issue.


The second choice is 'Golf Cart' batteries.
These are lead/acid (wet) batteries, and have all the usual issues wet lead acid batteries have.
While being 6 Volt DC (you will need 2 for 12 Volts) these are the most common true deep cycle batteries so the price is lower per amp/hour of capacity.
Keep in mind, even being deep cycle, you still won't want to discharge the batteries below 25% to 50% depending on type, simply because doing so will damage the batteries.

In 12 Volt sets, these batteries are easily charged by any common vehicle alternator, battery charger, etc.
They are very forgiving regarding charge input.

----------

The charging of batteries.

This can be Solar, Hydro, Wind, Generator/Vehicle, even hand cranked generators.
As long as the input voltage is between 14 & 14.5 volts per 12 volt batteries/sets the battery/batteries will charge.
(Horror Freight sells analog volt meters for $5 or less, and can monitor your charging in real time, don't need batteries of their own to work)

Charging batteries is pretty straight forward, not much to it.
Using a gasoline/diesel/propane genset & battery charger will make it a snap, using a vehicle's charging system makes it a snap.
Solar, wind, hydro will need a $20 charge controller between batteries & generator.

--------

This is your power storage without undue cost.
If you can't build a battery box to contain, and protect batteries, then don't try this.
If you can't practice common battery maintenance & safety, then don't try this.
If you can't make cables with proper terminals, then don't try this.
If you can't wire a common DC circuit then don't try this.

I say again, batteries contain a HUGE amount of energy, they will burn through metal, they will explore, they will corrode EVERYTHING around them due to corrosive/explosive gasses...
Batteries MUST be secured so they don't get turned over, and they MUST be protected from puncture, damage and anything falling on terminals, and the box MUST be vented to prevent explosive gasses from building up.

I would suggest a heavy plywood box, stainless screws (low corrosion) WITH A LID, and closed bottom plastic containers inside to catch battery 'Sweat' which is corrosive. It WILL attack wood, metals, etc and if it's contained in a plastic tray in the wood box, it doesn't destroy your work.

I can't stress battery safety enough, safety glasses when working on your batteries!
The eyes are greatest asset you own, PROTECT THEM!

 

[edwea]

Fwiw...see nec 110.14.
Splices must be MECHANICALLY secured WITHOUT the use of solder. Solder may then be applied.

 

[deo62]

Been a lineman for 30 years, guess I've been doing it all wrong

 

[JeepHammer]

That's just absolutely false.


Skin effect, inductive impedance, and stray capacitance all combine to make AC electrical transmission more inefficient that DC. The higher the frequency, the worse it is.

And here we go with semantics... Thread bombed by someone wanting to argue instead of contribute...
Misunderstanding the small scale systems, instead quoting from the bible of big grid systems.
And in the process, completely wasting time that could help explain the small systems, while confusing anyone reading about small systems...

--------

First off, I'm sure you are going to quote line losses with high voltage lines used on the common grid, which are aluminum or steel. (Or possibly copper clad steel)

At no point did I say to use aluminum or steel, I use copper only simply because copper minimizes losses in all cases.
The ONLY better conductor of current is silver. I can't afford silver wire and I'm guessing no one else can either...

Secondly, the frequancy of AC current in a small system will never exceed 60 cycles, this isn't aircraft, spacecraft, large ships or submarines running 400 cycles,
OR,
This isn't communications equipment that can run in the gigahertz range.

This is EXACTLY what I was specifically avoiding, trying instead to get a system up and running for someone, you want to argue semantics & electrical theory.

Third, power grids drive VOLTAGE up to avoid Amperage, a small system will never exceed 220-240 volts or 60 Hertz cycling.
Lower voltage reduces line losses simply because you aren't trying to push 14,000 volts through any given conductor.
The more you try and push, the more you loose to resistance loss...

Fourth, there is no point in trying to define, then explain effects of impedance, capacitance, etc when they simply won't apply in the case of a small system.
The components will come with fixed resistance, capacitance, etc, and without extensive education & experimentation you simply won't change anything.

Do you REALLY think anyone is going to rewind the generator, motors, etc to 'perfectly' match any given application,
Or do you suppose they will use common water pumps, electric motors, generators, etc?
I'm betting they will use commonly available units...

Fifth,
Again... This IS NOT aircraft, spacecraft, submarines, large navy ships...

The BEST DC connection is simply a soldered joint.
We aren't worried about the solder stiffening MINIMUM gauge wire sizes (wire is weight) making them break off with high frequancy vibration of the ship, aircraft, submarine, etc.
Soldering battery cables in particular (which is what the conversation hasn't progressed past yet) is a sold, long term and dependable connection.
I do NOT need to consider high frequancy vibration from turbines, I do NOT have to consider regular replacement of wiring harnesses on a set schedule like systems in submarines, aircraft, etc have.

My systems have run quite efficiently for over 15 YEARS simply because I build them bullet proof FOR THE APPLICATION at the beginning...
I do track efficiency, and I do track maintenance & maintenance costs.
I DO NOT tell people to buy a $300-$1,000 terminal crimp tool to make simple battery cables, which are REQUIRED for aircraft, spacecraft, submarine applications you quote...

APPLICATION!!!, APPLICATION!!!, APPLICATION!!!

Sixth,
If you want to chest thump, showoff, start your own thread teaching FROM SCRATCH, advanced electrical theory, then progress into graduate classes in electrical engineering theory...

 

[JettaKnight]

Been a lineman for 30 years, guess I've been doing it all wrong

You don't carry up the pole a soldering pencil with a really long extension cord?

Here's some guys working on circuits where connection resistance is a really big deal:
[video=youtube_share;sZFT6_BUxqY]http://youtu.be/sZFT6_BUxqY[/video]

 

[JettaKnight]

A humorous look at AC vs. DC power transmission.
[video=youtube;DFQG9kuXSxg]http://www.youtube.com/watch?v=DFQG9kuXSxg[/video]