Bergey Wind Generator -

[MountainDon]

Pure sine wave AC output is much kinder to all motors. They run much cooler and also use a lesser amount of power. In the end worth the expense because you no longer have to worry about what AC units might not like the modified (actually square, nothing much modified about it) sine wave. My wifes computerized sewing machine wouldn't run on modified. I also toasted a couple of rechargeable devices on a modified sine inverter.

[peter nap]

That is even better!

Right now I'm pumping non potable water from a spring to a tank using an Agpump (gas)

In the new place, I'm still going to separate the non potable and the drinking water. The non potable which is spring water and I drink it all the time, is what will run the hydro. I had planned on using pure hydro power to run a pump to a tank at the house.

The well water will run off a 12 volt pump.

[glenn kangiser]

I got about half again more water from the same power when I switched to pure sine wave.  There are little mickey mouse devices you can add to make the pump a bit better but why bother when the ficx of pure sine is better for everything.  I know --- it cost quite a bit more.  I did well getting my second one on Ebay.

[glenn kangiser]

Grundfos makes a very good pump that runs directly off of the panels. -- No batteries required for a deep well pump.

[peter nap]

[highlight]I got about half again more water from the same power when I switched to pure sine wave[/highlight]

It;s in the budget for the new cabin but like you said earlier, the learning curve is expensive.

[tanya]

Do the towers have to be that tall?  My desert land is wide open space and the big winds blow constantly, plus I think the association codes limit the heights to 24 ft.  

[desdawg]

If I had a cat underfoot I would want to be able to nuke it 24/7 so I see where you are coming from.  

[glenn kangiser]

Do the towers have to be that tall?  My desert land is wide open space and the big winds blow constantly, plus I think the association codes limit the heights to 24 ft.  

The wind is much better up there. Around 20 mph puts out pretty good power.  If you live in an area with an association it is not likely they will want one around.  While it is relatively free power, the neighbors will all want their say and at least one won't like it.  It does make a reasonably pleasant whirring noise and harmonic noises at times.  You also need 30 feet clear above any tree top - roof top or obstacle that will cause turbulence and slow the wind or make it behave erratically.

The cat , desdawg.  Not worth much except to look at but she does purr until I go to sleep.  I guess that's worth something.  Guess I better leave her alone.

[Okie_Bob]

Glenn, I'm glad you made this a separate topic and maybe you could save it as I believe more people are going to be looking at alternative power pretty soon. I know I am.
Great input for all you guys on this subject. I feel like an idiot not knowing more about it as I do have a degree in EE. Just never really considered wind power as ready for prime time yet. Solar has been so expensive it hasn't been worth a look either. Appears that may have changed.
Tanya, if you go to the Bergery site Glenn gave at the first of this topic there is a whole section on why the towers need to be as tall as possible. So much more to consider than I had expected. But, with POA, it looks like you won't be going with wind power anyway?
I do still have a question about batteries. How long do they last? These are all lead acid, I assume? Seems that would be a rather large recurring cost since so many are used.
I have some knowledge of a solar powered battery charger that uses a pulsed charge that cleans the battery plates as it trickle charges the batteries. They are not too expensive and they claim some remarkable results of extending the life of lead acid batteries. I know an engineer that did some consulting for them and the claim to have gone to the city of Arlington, TX and asked for some batteries they had stacked up as dead, waiting to be picked up for recycle I assume. They put this pulsed charger on them and brought all be three of them back to useful operation again! Understand every Humvee in Iraq now has one on it from the factory. Just have to keep the little solar panel in the sun. I c an get more info if anyone is interested. They do sell them around here at Battery Plus stores.
Okie Bob

[peter nap]

Good idea to make this a sticky Bob.

This is a site that sheds a lot of light on solar and is very understandable to people just starting to think about off grid:
http://www.solarexpert.com/Batteries/batchart.html

BTW there are very big things happening with solar technology. One of the most exciting companies coming up is Ascent Solar and their thin film panels. It's one of the few small companies I own stock in. They are boosting the power while lowering the cost. The bad news is that There will be a long wait for delivery after they go into full production this fall.

They already have government contracts to fill.

[glenn kangiser]

I think the Trace regulators use Pulse Width Modulation which is what keeps the sulfate crystals broken down.  

Poor Mans Guides has a good wind power and battery rejuvenation in one e-book- tells you how to build both.  Good study for an electrical engineer----     or the poor man --- or anybody interested.  http://poormansguides.com/

They say 5 years on the L16's but PWM could increase that.  Also MPPT - maximum power point tracking on the regulater gives more power for the same amount of panels.

Poor Mans Guide tells how to build the rejuvenator that will rejuvenate forklift batteries which can have a 20 year life - usually lead with antimony added for durability.  A bit faster self discharge rate but not usually an issue in daily cycled batteries.

[Cyric30]

Ive been looking into alt. power for a bit now, and intend to use it on my home when i manage to build one (assuming i can overcome the technical hurdles set in front of me) and i second the poormansguide and also add www.otherpower.com they have some intresting stuff also

[peter nap]

Otherpower is good however, they are bad about answering a question with many snooty questions. When the answer is given, it's often in a form that newcomers can't understand.

[MountainDon]

BATTERIES: The longevity of batteries in a alternate energy system depends first and foremost on the care  and use or abuse they receive. They are generally flooded lead-acid batteries of varying degrees of quality. Some are lead-acid in a sealed AGM type. They have some advantages, but cost more per Amp-hour of capacity. AGM take more abuse in general. Gelled batteries are the least tolerant of deep discharges and overcharge rates. I would avoid them altogether.

The most common abuse is over discharging the batteries. Longest life starts with restricting the depth of discharge. Yes, they are called deep cycle, but the deeper the discharges, the fewer the number of charge/discharge cycles. Ideally you would only use 25% of the capacity before recharging. Most folks probably run them down to 50%. So sizing the battery bank correctly is the first step in achieving longer life spans..

Other forms of abuse include leaving in a discharged state and allowing the acid level to fall below the top of the plates. Battery life is also extended by performing an equalization charge once a month.

Here's a list or likely life spans beginning with a standard automotive cranking battery.

Starting: 3-12 months
Marine/RV deep cycle: 1-6 years
Golf cart: 2-6 years
AGM deep cycle: 4-7 years (this can vary considerably - the large 2 volt cells can last for 20+)
Gelled deep cycle: 2-5 years
Deep cycle (L-16 type etc): 4-8 years
Rolls-Surrette premium deep cycle: 7-15 years
Industrial deep cycle (Crown and Rolls 4KS series): 10-20+ years

The significant differences listed for Marine/RV deep cycle and golf cart batteries reflects poor care versus pampering.

The most significant difference as one goes down that list is the amount of lead, the thickness of the plates. This is a case where bigger is definitely bigger.

IF golf cart batteries can meet your power storage requirements they can be very good value.

In an ideal or near ideal battery system the number of parallel loops should be held to a minimum. No more than three batteries or series connected cells/batteries should be connected in parallel for minimum maintenance and longest life.

When deciding upon the battery type and configuration you would ideally choose the battery that will supply the power needed with the least number of cells or batteries. Some of the better (higher priced) batteries are available in single 2 VDC cells.

Battery weight must be taken into account for transporting and handling issues.

There's lots of battery information available on the 'net as well as a lot of sources to buy from, but because of the weight freight costs are usually quite high. Best to decide what you want/need and try to find locally, IMO.

I have had personal dealings with   http://www.affordable-solar.com/  and  http://thesolar.biz/Our%20Complete%20Product%20Inventory.htm    I recommend both.

Good information at  http://store.solar-electric.com/  but I've never bought from them.   http://backwoodssolar.com/  also has good info and a paper catalog full of info for free, but I the prices can be higher.

[glenn kangiser]

A couple more wind DIY links

http://www.scoraigwind.com/
Hugh Piggott - Scoraig Wind Electric

http://windstuffnow.com/main/

[Okie_Bob]

Mountain Don, great workup on batteries, thanks a bunch.
Now the question becomes, 'where do you put all these batteries'? How do you actually go about maintaining them? I would think you would want a constant trickle charge going to maintain them in as highly charged state as possible. No? I say this because as you point out, at least in marine batteries, the biggest problem is leaving them in a discharged state for long periods of time. Most fishermen used to take their boat out of the water, trailer it home and forget about hooking up a charger until just before they are going fishing again. If a good battery lasts one year, they are lucky. Now a lot of fishermen have built in, on board multistage chargers. First thing I go when I pull into my boathouse is reach up for the extension cord and plug in my boat. Starts charging immediately and I'm ready to go anytime I want. Has allowed me to use the same batteries for over 4 years and counting now.
Okie Bob

[Okie_Bob]

Almost forgot, thanks to all for the great sites links. At least now I'll know enough to be dangerous!
Okie Bob

[peter_nap]

Bob, you want to keep them in a vented box, outside if possible. If and when they start gassing, it's explosive so venting is a must.

I keep mine in a PVC box buried with a vent in the top. This keeps them at a constant temperture. You may not have problems with the cold though.

Keep the batteries topped off by a trickle charge. If it's just for standby, discharge them 10% a couple of times a year.

Check often with a hygrometer and keep the water topped off.

If you go with a 12 volt system remember to use heavy enough wire. I use battery cable. It draws a lot of current. If you have a 1 amp load at 120v, the inverter will draw 10 times the current from the battery or 10 amps.

You won't have any problems, this isn't rocket science.

[MountainDon]

Hey Okie Bob, you've already figured out how to extend battery life!! Keep them full!

Where to locate the batteries? First some more info. Batteries work and last best at about the same temperatures people like best. Batteries are rated at 25 C (77 F). As temperature increases battery life decreases while capacity increases. Conversely as temp drops battery life increases and capacity is reduced.

At freezing temp the capacity is reduced by 20%. At -22 F capacity is reduced by 50%. At 122 F battery capacity is increased by about 12%. At -22 F battery life is increased by 60%. For every 15 degrees F over 77 F life is decreased by 50%. However, if your batteries are in a variable temperature life will sort of average out.

If the battery bank is large and in an insulated box/container the thermal mass of the batteries will slow down the rise and fall of the battery temperature.

In any event your batteries should be located where they can not be accidentally shorted out. As mentioned batteries out gas hydrogen and oxygen under charge conditions. The higher the charge rate, the more gases. A spark can cause an explosion. Therefore the container must be ventilated to the outside in such a manner to be explosion safe. Hydrogen rises so a sloped lidded box with the ven at the high point will self vent with no need for fans. A low point air inlet will aid the venting process.

Batteries all self discharge when at rest. Self discharge is greater at higher temperatures.

So I guess I didn't really answer exactly where to put the batteries, but you can make a wiser choice now.

Hydrometers measure specific gravity of the electrolyte which indicates the state of charge. Make sure you leave enough room above the batteries to make hydrometer use easy. Also for adding water. Only add water to fully charged batteries as the electrolyte volume is greatest at full charge. The exception to this would be if the top of the plates are exposed. If so, add just enough water to cover the plates. Top up as necessary when fully charged.

The best hydrometers are those with the graduated float cylinder, not the ones with the floating balls. AGM batteries can not be measured with a hydrometer;they're sealed. One must make do with voltage readings. Voltage readings should be taken after a period of inactivity; no charging, no discharging. Six hours without use is usually enough for the voltage reading to become more correct. Under load the voltage decreases and then rises when the load is disconnected.

When charging batteries with a stand alone charger the preferred charger would be one that has built in multi stage charging. Bulk, the highest charge rate, Absorption, an intermediate range that tapers down, and Float, to maintain the charge. I have chargers that go thru the range depending on battery state of charge. When the battery is full there's next to no charge to the battery. If the state of charge drops the charger boosts up. Mine are made by Iota in Arizona, USA! They have several models with varying capacity. I swear they are the best stand alone chargers out there. Variable speed fan cooled as necessary. Get the IQ option for auto charge regulation. They make 12 and 24 VDC models.

http://www.iotaengineering.com/

Most DC to AC inverters that are designed for alternate power situations (not the cheap types found nearly everywhere) have a charger built in. If/when connected to a source of 120 VAC power they will maintain the battery state of charge. In most alternate energy systems there is no permanent 120 VAC connection. The wind, water or solar source is what maintains the charge. In those situations the batteries should be run through an equalization charge (higher voltage charge, about 10% higher than the usual highest rate) once a month for best battery life.

[glenn-k]

That brings us to the point that when you are totally off grid there is no place to plug in a trickle charger.

Batteries that are allowed to sit and discharge then not used for six months or more may be sulfated so badly they will not come back.  Some of the new PWM chargers may bring them back but don't count on it.  The Poor Man Guide recommends that even if you get an old forklift battery to rejuvenate, it should have some charge in it and even then you may be talking a month or two with the pulser charger on it to bring it back.

In general batteries that are cycled daily will not get sulfated so badly.  

One solar professional I talked to recommended equalizing clear up to about 30 volts for several hours on a 24 volt system to desulfate and bring the capacity of older batteries up.  This may cause you to need to temporarily remove the batteries from your system as the inverters may cut off at that point.  I tried it once and it did work -- I am a bit of a battery abuser and don't get up to equalize voltage very often.  

When off grid you will likely have to kick a generator on once in a while to get up to equalize voltage unless you have a great quantity more panels than you need - which most likely wont often happen --- but it should.  Regulators will prevent over charging when not equalizing.

[Okie_Bob]

Glenn, there is a solar powered pulse charger available. Mainly used for boat batteries can be used anywhere you have sunlight.
The solar panel is a flexible piece of material about one sq ft in size or maybe a little smaller. Obvioulsy, it is only a trickle charger but for applications where you are off grid seems like to me it would be worth trying? There is a chain  called 'Battery Plus' around here and they have them in stock and I believe the retail price is around $60 but could be way off base with that.
Okie Bob

[glenn-k]

If I am not mistaken, the Xantrex C40 I have is a pulse charger.  PWM - pulse width modulation -- I don't know much about it though.  The small chargers are great for equipment etc that is not used but expensive per watt for other uses.  Things should typically be under $5 per watt.

A small charger would not keep up with my parasite drains -- phone chargers - light on microwave-coffee pot clock - etc.

[MountainDon]

IMO, an alternate energy system that is being used doesn't have any need for a small "trickle" charger of any sort. The system batteries usually need to be charged at higher rates because of supplying power for the electrical loads it was designed to power.

Small low rate chargers (being run off a 120 VAC circuit or small special purpose solar PV panel) are mainly useful for maintaining a state of full charge in a battery that is waiting to be used for something. One thing to watch for is having a charge rate that exceeds the rate of self discharge by too great a factor and cooking the battery... resulting in low fluid levels and plate damage. That's almost as bad a letting the battery sit there at a low state of charge for extended periods. If you're like me you may try to keep an eye on fluids, etc, but sooner or later time manages to slip by and when you look the fluid is lower than you expected.

This is a wind generator thread and I don't know a lot about them other than I know they require a diversion type of controller as they cannot be switched off like a solar PV panel can. The information below on PWM and MPPT chargers comes from my solar power research & experience.

There's absolutely no doubt that PWM controllers are vastly better than the older relay or transistor controllers, still found in some cheap units. The newer MPPT controllers are even better, really coming into their own providing the most available power under cloudy skies. They're also better in winter when you are using more power and not making as much due to shorter days.

...PWM - pulse width modulation -- I don't know much about it though...

PWM info here... from Mornigstar, producer of PWM units
http://www.morningstarcorp.com/support/Why-PWM/why-pwm-1.shtml
Be sure to click on "Next" at the lower right to read the subsequent pages

controller info here...
http://www.solar-electric.com/charge_controls/solar_charge_controllers.htm

MPPT info here...
http://www.solar-electric.com/charge_controls/mppt.htm