True from-scratch storage.

[Texas Al]

First of all, let me explain why I want a DIY energy storage solution when deep-cycle batteries are readily available at the local WalMart.

1) Each specialty good we buy new puts us on the grid economically even if not physically. A lasting grid-failure would therefore deprive us of replacement batteries just as surely as it would deprive the average person of electricity. Very common items (i.e. car parts, appliances, bulk construction materials) are okay, though. Basically anything that would still be around or even in surplus in the event of grid-failure.

2) Being able to build batteries or other power-storage devices will give us the knowledge and confidence to also repair batteries whether they are commercial or home made.

With that out of the way, here are my questions:

1) Are there any battery chemistries that can use commonly found metals which are less toxic than lead?

2) If not, does anybody know of any links for practical, hands-on information about lead safety? (there are plenty of articles about how bad lead is, I'm interested in specifically how an individual who is working with lead can actually protect themselves)

3) It's my understanding that a wet-cell battery needs lead plates as well as lead-dioxide or lead-oxide plates. Now, the lead plates can probably be made from flattened pipes or something... but what about lead-dioxide or lead-oxide? Are there any commonly available substances or objects that contain lead-oxide?

4) If our goal is to store 4kW of power... what would be the most practical form of physical storage? We did calculations on elevated water storage, and came up with flows of 120 foot-gallons per minute, which translates into a tank 30 feet on a side (if it was a cube) standing one foot off the ground, and smaller tanks at higher elevations but still something on the scale of a municipal water tower and so not buildable by us in the forseeable future. Are there any physical energy storage setups that are smaller and easier to build?

Thanks for your help!

[kitno455]

super critical heated water, and a steam turbine. you can make superheated water with electicity, waste oil, wood, parabolic solar, etc if you have a well, its free. the only problem is the boiler

allan

[Texas Al]

But isn't that a form of power generation rather than storage? If we're using windmills, I could see how the electricity could power a heating element (ugh, wasteful) but if the wind dies down for a while so would the steam turbine... or are you basically saying to give up on storing electricity and just switch over to combustion whenever the windmills aren't putting out enough?

[kitno455]

its a lesson we learn from the junkyard wars (scrapheap challenge) tv show. when you are in a neandertal situation, use the neandertal solution. blimp, not fixed wing, black powder, not smokeless, etc.

if you really are crazy enough to believe that the whole world is going to reboot, then you have to assume that you are going to start from pre-industrial revolution techniques, and work your way up. which means, you start where the Ind.Rev. started. wind mills and water wheels doing physical work, combustion boiling water.

if a boiler full of supercritical (pressurized) steam can be insulated well enough to stay above the flash point for a few hours without external input, then you build a closed system, and it will continue to make power for at least a little while, if your system uses dual tanks (dont want to put the condensate back into the hot tank without heating it first)

btw, your idea about 'oh, i cant make car parts, so those will be assumed to be available' is bunk. either you believe this impending doom, or you dont. take a look at what the mechanics is cuba can do. they hand-forge waterpumps for their 50 year old US cars.... i am not saying i agree with yout (in fact i disagree strongly), but your logic for why this enterprise is needed is full of holes.

allan

[Norm]

   The most practical DIY energy storage is a

home-brew flywheel....You don't need to go into

super-flywheels spinning at 300-500 thousand rpm.

  ...just a spinning truck tire (well balanced)

at equivalent of 80mph.  direct drive motor/ alternator...

set down in a cement enclosure...sealed up and

evacuate some of the air(so it wouldn't have air friction

to slow it

down)could store a couple of watt hours.

    A windmill genny to keep a bank of these

charged up...

                ( :>) Norm.

[PHinker]

I'm up for some 'blue sky' thinking and this is a subject dear to my heart.  I've always been resistant to the thought of battery storage due to all the disadvantages (which I won't reiterate since most folks are quite familiar with them).

How about this.  Instead of generating electricity at the top of your tower, why not place a compressor there?  Instead of a lattice or pipe tower, why not pour a hollow concrete column into which you store the compressed air?  Now, run 'transmission lines' (i.e. air hoses) from your tower to your generation shed where you have an air motor and an alternator.

   Disadvantages:

      * Air motors are inefficient

      * Air compressors are inefficient

      * Torque required on a compressor increases as pressure in the 'tank' increases

      * Pouring an air tight 30' column is difficult

   Advantages:

      * Multiple towers can be connected without regard for 'syncing' the generators.

      * Expanding the system is straightforward

      * Alternator and air motor matching can create very 'clean' power.

      * Low transmission losses from tower to generator

      * No batteries to buy/maintain/dispose

      * Used compressed air can be used for cooling

   Lots of questions about this which I don't have answers for.  What would be the optimum pressure range for the system?  How thick do tower walls need to be for a given air pressure?  How do you match rotor swept area with a given compressor displacement?  Can you solve the problem of increasing torque requirement for the pressure range you need?

[pyrocasto]

You have probably the 2 better ways of saving power. Compressed air, or water tank.

Compressed air like said before, just using a compressor on the genny.

If you have a hill, you could easily put a water tank a good elevation up, and pump water up there to store it. When you need power, release some water. Some big time dams do this when they have extra power.

[ghurd]

There are used propane (?) tanks refitted for air. Up to 1000 gallons each, and they regularly see 130PSI, always over 80PSI.  The 500 gallon ones are $275 right now for sure, 1000 gallon was about $350 last I knew.

Cheaper and easier than concrete.

[Norm]

  A triple expansion air motor is pretty efficient....

                 Norm.

[scottsAI]

At 10 foot hight = 30x30x3 foot pond not very big.

Or, use 4 gal of gas in a generator. Cheapest solution.

Lead is a problem if it gets into your body. No chance in a battery, unless you like to eat it. If this were a problem, why would it be in your car?

Your body can't digest pure lead, requires a binder, like paint has the lead bound in it chemically. Lead is very bad for young, makes them retarded, not much a problem for adults. They don't eat paint, and does not bother them much anyway.

Lead is not very reactive, the European mandate to remove lead from electronics is one of the many wives tales, that is just so obvious it's right, I have not seen any credible testing.

Which will fall faster a 1 lb lead ball or a 1 lb turd. Today we know the answer...

Lets say you have a glazed donut, if I rubbed off the glazing in one spot of your glazed donut, would you say I made a hole in your donut? No, but that is the issue with ozone depletion. 4% thinning at the north pole, a number before 1980 we could not measure. A number that has not been proved to mean anything. May be natural to to the location or a naturally occurring event, data of late suggests it may date back before 1900's. Other data suggest cycles with sun spot activity. Whom are we to believe?

Have fun.

[PHinker]

I haven't seen any for that price but I would agree that propane tanks would be a good storage solution.  I just kind of like the elegance of combining the tower with the storage.  Plus, I have some experience with slip-formed concrete structures (grain elevators).

Paul

[PHinker]

I'm not familiar with triple expansion air motors, Norm.  Where can I learn more about them?  Thanks,

Paul

[Texas Al]

As I mentioned in my post, this would take a hefty water tank unless my calculations are off. And no, our test site is flat, unfortunately.

[Texas Al]

> At 10 foot hight = 30x30x3 foot pond not very big.

If you already have one.

> Or, use 4 gal of gas in a generator. Cheapest solution.

It is at the moment... and that's exactly why so few people invest in renewable energy. I'm trying to think a few steps ahead.

Now, if anybody has the numbers on how many acres of sunflowers or canola it takes per gallon of biodiesel, that would be useful information.

[Texas Al]

This is interesting. Anybody know how to go about calculating what volume and pressure  of air it would take to store, say, one kilowatt-hour?

[Tyler883]

I know its impractical for many people, but water stored in an elevated location is an excellent way to store energy, or even collect it if you get lots of rain.

[Tyler883]

Another great way to store energy is take a gallon of gasoline and put it in your chainsaw, then use it to get a truck load of firewood.

[fishfarm]

This information was posted earlier:

http://www.fieldlines.com/comments/2005/4/29/151025/082/2#2

[Texas Al]

With the usual caveats about using up your wood supply faster than it can renew itself, and there being competing uses for wood as a building material.

But if one goes that route, I wonder if it would be more efficient to convert the wood to charcoal and town-gas. Never tried it, just wondering.

So far, though, the compressed air and the flywheel approaches might work. I like the flywheel idea because you don't even have to convert from mechanical energy if you're using a windmill. The windmill just cranks the flywheel directly.

[Big All]

For alternative to Pb/acid batteries, we had a short discussion about Ironclad or Edison or FeNi batteries here

http://www.fieldlines.com/story/2005/4/15/20834/6559

I still haven't come across homebrew info on these yet though.

[moodyalex]

Rather than water, what about just using mass. Like old clocks used too, you could have a hollow tube tower with a great big weight in the centre. The mill could lift it up, and when you want power you let it fall.

Would require some good gearing but should be possible. I would imagine a lot less wastefull that water pumps / generators and air ones too.

Cant see why it wouldn't work, except maybe the huge size of weight required.

Alex.

[chux0r]

You might be fine with your FLA's.  If the world "reboots" as Allan says, you won't have any use for your radios, TVs and whatnot.  Assuming you've stockpiled CFL's (you can buy a case of 48 for a couple hundred bucks) you can have lights for the rest of your life, even when your 300Ah battery bank only stores 10Ah.  Your fridge is long dead, and you're getting on in years so you don't much care.  It's an interesting topic, but I agree with the folks that say this will actually be the smaller of your problems.

However, the post on nickel-iron batteries is quite interesting!

[pyrocasto]

But of course on a non windy day, no power. You would also have variations in speed and such.

[PHinker]

Well, that's going to depend on the efficiency of your alternator/generator but let's say you have an 80% efficient alternator like one that DanB or Hugh builds.  I've seen air motors which will produce about 1.6 hp on 22.5 liters/second of 91 psi air.  80% of 1.6 hp is pretty close to 1 Kw (1.6 hp * .80)/746 watts/hp = 954 watts.  So, you need 22.5 liters * 3600 seconds = 81000 liters @ 91 psi.

To put things in perspective, if you're going to feed the air motor directly from a run of the mill compressor you would need something like a 20 hp driven compressor (something that will produce ~26 SCFM per minute @ 90 psi)

Now, there might be more efficient air motors and compressors than those used in these calculations.  However, it looks like such a system would have an overall efficiency of 5% or less.  Probably not the best solution.

Paul

[Texas Al]

Exactly. And that's why I posted a question about power storage in the storage section of the energy board.

[Texas Al]

Sorry but I'm SOL trying to understand your TLA's. ;-)

FLA = flooded lead acid?

CFL =

Thanks.

[farmerfrank]

Compressed air, although cheap and from scrap runs into storage problems due to regulations. Air tanks above a certain volume and pressure are supposed to be inspected and tested as I'm sure all us tinkerers would do...haha.

Using homemade power , actually any electicity, can be used in an electrolysis process to make hydrogen. Now hydrogen is highly explosive over a large range but I don't think it is regulated yet. Not condoning it but I think it is a very practical solution. Anybody else care to comment?

[Texas Al]

> if you really are crazy enough to

> believe that the whole world is going to

> reboot, then you have to assume that you

> are going to start from pre-industrial

> revolution techniques, and work your way

> up. which means, you start where the

> Ind.Rev. started. wind mills and water

> wheels doing physical work, combustion

> boiling water.

I don't consider myself crazy. But then again, crazy people seldom do. I never said that the whole world is going to reboot. It doesn't have to... it would make me plenty unhappy if, say, some natural disaster rebooted just the little corner of the world I happen to occupy. It would even make me unhappy if some opportunistic human beings decided to rip me off because they had a monopoly over something I depend on.

That being said, I do believe that everything comes to an end, including civilizations. I don't know when, I don't know how, and I don't know if it would even be during our lifetimes. But given enough time, it will happen to us too. In order to disagree with me on this basic point, you would have to believe of all the civilizations that existed throughout history ours is the first that is invulnerable to collapse.

Given that collapse could happen, there is some optimal fraction of our energy that would be rational to dedicate to contingency planning. Not completely uprooting our lives and heading for the hills, but at least taking stock of what we are not willing to live without and figuring out the minimal series of steps it would take us to insure an uninterrupted supply of it.

Maybe I am crazy, but I think it's more of a harmless eccentricity that would, had I been a passenger on the Titanic, compelled me to memorize the locations of the nearby lifeboats and life-vests "just in case", even though all reasonable people knew at the time that something that big simply couldn't sink. ;-)

[Texas Al]

But, if it catches on, won't we have problems with hydrogen emissions accelerating ozone depletion?

[nanotech]

FLA = Flourescent Light (?)Array

CFL = (?) Flourescent Light

[nanotech]

Hit post before I remembered what the C is.  Compact.

[Texas Al]

> btw, your idea about 'oh, i cant make

> car parts, so those will be assumed to

> be available' is bunk. either you

That's not what I said. They're not available because I can't make them. They're available because we produce massive numbers of cars and junk them after 5-10 years of service. In the absence of fuel (which would be the second thing to go after electricity in almost any feasible grid-failure scenario) demand for cars (and all sorts of other gas-powered appliances) will drop, resulting in even more cheap/free cars for the taking.

Can you think of a disaster that would make abandoned cars scarce?

> believe this impending doom, or you

I never said the doom is impending. It makes no difference to me if the next dark ages comes along during our children's, or grandchildren's time. Whoever is around when it happens will need to know how to generate and store electricity because it leverages all the other modern technologies.

> dont. take a look at what the mechanics

> is cuba can do. they hand-forge

> waterpumps for their 50 year old US

> cars.... i am not saying i agree with

Actually, there's a series of books on home metalworking by David and Vincent Gingery that I've been meaning to buy. I used to think that metalworking is out of the ordinary person's reach, but I no longer do.

> yout (in fact i disagree strongly), but

> your logic for why this enterprise is

> needed is full of holes.

I'm glad you think so, I'm always looking for ways to debug my thinking. Let's just make sure we're on the same page, though.

All I'm really trying to do is identify the minimal set of items I'd need to have in order to obtain everything else. Call it a mental exercise, a puzzle, if you like.

For generating electricity, I've concluded that the only part I can't make or make do without are magnets. So now I've moved on to batteries. I'm trying to figure out if one or more of the following is true...

a) They can be made from scratch.

b) They can be reduced to some minimal component that cannot be made from scratch, but once you have it, you can build the rest.

c) There is an alternative to batteries that can be made from scratch or can be reduced to minimal components more than batteries can.

[Texas Al]

Actually, my scenario involves not only me but also my neighbors and their descendents living in humane and pleasant conditions for an indefinite period of time and teaching their neighbors how to do what they do while accumulating enough surplus resources and time to pursue ever more advanced tinkering with each decade.

So no, I don't think 48 fluorescent light bulbs or whatever it is CFLs are, will be anywhere near enough. ;-)