Thomas Allen Schmidt's posts

When sizing any PV source circuit one must first know the "short circuit amperage" or Isc. This should be on the specification tag on the back of every PV module. After one has that number multiply it by 156%. This is per UL and NEC. Thats 125% for UL and 125% on top of that for NEC or 125% X 125% = 156%.
Lets say one has 4 PV modules with an Isc of 4.5 amps each at 12 volts nominal and they are wired in parallel.
4 x 4.5 x 156% = 28 amps
Not probable, but possible. Thats the NEC for ya!
This is the  number that one would size the; wires, fuses, disconnects, and charge controller by.
I have had this happen on my system only once in 6 years and it lasted only about 2 minutes.
It was noon time, temperatures where in the low 20's, snow on the roof, and there were those certain types of clouds that cause that "edge of cloud effect' and I was equalizing the bank.
 As for paralleling multiple charge controllers...
Working with them one at a time, set the voltage set points as close as possible to the same as each other controller.
Chances are they will come on line at slightly different times in the morning and go off line at night at slightly different times.
UL - Underwriters Laboratories
NEC - National Electrical Code

I am not so sure I understand, "a six circuit manual transfer switch"? A 6 pole transfer switch?         
As for the 1800 watts for 4 hours thats easy. Just pick a nominal battery voltage like 24 and divide.
4 x 1800 = 7200 watt hours load.
7200 / 24 = 300 amp hours
300 x 2 = 600 amp hours total capacity at 50% DoD all at the 20 hr. rate of course.
The reason for at least doubling the needed amp hours is to extend the overall life of the battery bank. Personally I would multiply by 5 for a 20% DoD (Depth of Discharge.)
As for turning all of this into 240 vac? or 120/240 vac? Just go to the store and start reading the specs. on inverters. Some have chargers some don't. Read the specs..

They all suck!
I rather french a sow hog than run an internal combustion engine generator!

Something I neglected to tell you was that sometimes positive and negative are "Daisy chained" form one box to another box continuing a branch circuit that is supplying power for other needs throughout the house.

It sounds as though you might have a "traveler" wire mixed up with a line or load wire. 
One way is - positive and negative would enter one switch box. The pos. (line) would terminate on that switches common screw. Two travelers would terminate, one each on the other two screws. The travelers along with the neg. would then go to the light box. This is where the neg. would terminate on the screw for the outer threaded ring of the lamp holder. The two travelers would then continue to the next switch box and terminate the same as before. Then pos. (load) would come off of that switches common screw and go back to the light box and terminate on the screw for the center pin of the lamp holder.

Even though the wires may be run differently from house to house the principle is the same. For example; pos. and neg. may enter at the light box but there only needs to be three conductors going to each switch box. Two travelers and line to one switch, two travelers and load to the other switch.
 
With the circuit dead and all wires separated at each box use a meter that can "ring out" continuity and identify each wire at each box with colored tape. Make pos. red and neg. black. Make one traveler blue and the other orange. Once everything is identified I think it will be an easier task for you to figure it all out. Easier said than done I know. (One of my money making skills is troubleshooting industrial motor control wiring at places like, but not limited to cotton gins.) You will need a Length of wire and maybe some help to accomplish this. If the common screws on the switches are not identified by the manufacturer you can use that same meter to find out which is common because only one screw will "ring out" to the other two depending on how the toggle is positioned.

On a side note - what clarified 3-way, 4-way switching for me was hearing the words, "you can have as many 4-ways as you want as long as there is a 3-way at each end."

 Knowing your travelers from line from load is the key.

Have you ever opened one of those older style wooden windows with the counter weights hidden in the jambs and attached to the sash with rope across pulleys on both sides?
I cant say that this would be any easy fix or that it would be a quick or inexpensive fix because I cannot see just how your array rack is built and so on.
The idea is simple though. Two poles, one at each end with a beam across them to support at least two pulleys, tie a couple of ropes onto the array rack, toss them over the pulleys then tie on the counter weights. Of course the are always things to consider such as safety and longevity. If your not sure just how to go about doing something like this or where to get materials for the job, check to if there is an awning company in your area the makes pull up canvas awnings still. Shucks! looking at some retractable awnings might even give some better ideas of your own on how to deal with this minor hitch.

I once kicked around the idea of a large paddlewheel driving a relatively small 3 phases 480 vac genny (because of wire run and voltage drop) all mounted on pontoons. The 480 vac would of course need to be reduced and rectified for battery charging.

At my place the drop in elevation is inches over acres and seasonal but a steady flow most of the year. It can sometimes be zero water during a drought in August to 8 foot above normal in September. This is an extreme. It happened only once during hurricanes; Dennis, and Floyd. http://www.waterwheelfactory.com/

I am still waiting for a free pair of salvage pontoons.

However you can manage it, true deep cycle flooded cell lead acid batteries must be kept from freezing. Optimum performance happens between 70 and 80 degrees Fahrenheit. Remember that batteries convert electrical energy into a chemical energy and this is whats stored.

120 multiplied by 3 equals 360. Assuming that the load is constant for 24 hours a day that equates to a 8640 watt hour day. Divided by a nominal battery voltage of 48 this would equate to nothing less than 180 amp hours of storage. 8640 divided by 4 hours of equivalent full rated charge this would be nothing less than a 2160 watt PV array. (One could supply ample power for a modest home with that.) It would be curious if you have not considered building an enclosure for this exposed water supply pipe. Maybe something along the lines of a small insulated greenhouse. This would reduce the need for a heat tape to run 24/7. Or if a "waterjacket" could be created around the pipe to store heat for use at night, as well it might incorporate a small vdc element greatly reducing the size of the batterybank and PV array. Or if possible cover it with a goodly amount of wood chips and cover that with black tarp. Or... well it always comes back to this with me, mankind managed to survive on the planet Earth for thousands of years without utilizing electrical energy. We are testimony to that fact. It would seem that in only the last 100 years we have devolved to a place where we cannot survive without the utilization of electrical energy. Pity about Earth.

I would appear as though your thinking about using the well as a means of electric power generation. Is it an artesian well?

I am to late with this bit of information I am sure. I am surprised that no one mentioned it really. Its climate and average ambient high temperature for your region vs. PV module rated voltages. Yep! voltages, plural. There are three different voltages to one PV module.
1. the nominal voltage.      for example 12
2. the open circuit voltage.             21
3. the working or voltage.               17
Its the last one, the working voltage that is an issue with your regional climates average ambient high temperature. The higher the temperature say, if its tropical for example, then the higher the working voltage should be. Something in the order of 18 vdc or even 23 vdc for example on a 12 vdc nominal system. In contrast if its a colder region like Northern Alaska one might get ample power from a 14 vdc or 16.9 vdc module on that same nominal 12 vdc system.
By why would you want to?
If the higher voltage works so well in the heat then its really going to crank out the power in the cold!

Some of the first "modern type" PV modules I ever bought where the Solarex MSX77's with a working voltage of 16.9. When I say modern type, I am referring to those that came with frames, j-boxes, and warranties of course.
On the particular system these where working on, during the summer they didn't have an easy time of recharging the battery up to 100% each sunny day and one could forget about equalizing. While during the winter, they excelled at charging and they could equalize. This is in the southeast region of the north American continent.

The gist of all is - the hotter a PV modules gets the lower its working voltage gets and this goes for all PV modules.
I am truly surprised that the PV industry is not incorporating some sort of thermal electronics to the back of PV modules in an effort to generate even more power from a single PV module. Of course this would drive the cost of an already over priced item even higher.
http://www.powerchips.gi/index.shtml

Are you stating that the portable solar oven that is pictured on the link can reach temperatures of 300 C? Thats 572 F.
Now correct me if I am wrong but increasing the size of the portable solar oven by say... a factor of ten, would not increase the temperature by a factor of ten, it would only increase the volume of solar heated space by a factor of ten.
 As well the best way to increase the temperature would be to multiply the number of Sun's by a factor.
 Such things have been done with parabolic mirrors aimed at the Sun but the Sun's reflections all set to a central point which can reach temperatures in excess of 1,000 F.

 Here is a web site that you may find interesting while completing your research.
http://www.redrok.com/main.htm

I look at it and all I see is a big'ol pot of steaming hot beefstew with taters and onions and carrots and barley and all on a cold winters day. Maybe some buttered sourdough bread.

Kidding aside, what you are proposing may or way not be cost effective. I will be interested to see your economic figures on future updates of your site.

Motor nameplate amperage ratings are genrally high. They are for the most part what is known as locked rotor amperages. But for the purpose of calculating a PV system for a specific load such as the motor you describe, it would not be a bad idea to use it as is, because of all the potential power losses intrinsic to a PV/battery/inverter power system and of course, the weather. So...

120 vac multiplied by 12 amps equals 1,440 watts.
1,440 watts times 24 hours = 34,560 watt hours or 35 kWh.
Since PV output will last the equivalent of about 6 hours of the day, that leaves 18 hours of reserved time for another power source. But to offset the total energy needed with a grid interactive PV system one still needs to use the entire 35 kWh load in this example. So...

35 kWh divided by 6 equals a 6,000 watt or 6 kW PV array, not mention a grid interactive inverter that can send this power back onto the grid, preferably through a bi-directional meter. That will depend largely on your local electric power supplier or EPP.

6 kW PV array times $5.00 a watt equals $30,000.00, chances are your paying about $0.09 a kWh to your EPP? If so that same 35 kWh is costing you about $600.00 for 6 months unless it runs 12 months a year. So think about that. With that PV array, the other half of the year it will be "earning" almost $600.00 in savings. In other words in the summer the pool doesn't cost you anything and during the winter your earning money, in a manner of speaking.

All in all your looking at a payback period of about 25 years or more.

Is it worth while? All I can say to that is, not for me it wouldn't be. I live off grid.

A bit of news concerning electric power I just discovered about Uganda for anyone interested!
http://www.allbusiness.com/periodicals/article/1183719-1.html
It would seem that they want to encourage the exploitation of solar energy.
One thing would seem certain, whoever is responsable for the mining of raw silicon minerals from our Earth for the production of PV cells could become, if they haven't already become, one of the, if not the richest, aristocracies this planet has every known. Their future for generations to come is secure, that I do know. Dare I compare it to other aristocracies that have gained their fortunes by striping our Earth of a natural resource such as trees, or fossil fuels, fresh air, and clean water? I guess time will tell!

Here is some information about those heavy flywheel generators I mentioned.
http://www.globalspec.com/FeaturedProducts/Detail/ActivePower/Cat_UPS/4486/0
There is also the microturbine generator which can utilize methane from wastes as well as provide a significant heat source for such things as ammonia adsorption chillers, sterilizers, anything that requires temperatures of around 500 degrees Fahrenheit.
http://www.microturbine.com/
 It may be beneficial if community monies were "pooled" in an effort to create a local electric cooperation utilizing microturbine generators with heavy flywheel generators to increase the reliability of electric power to the entire community. This may or may not be of intrest to your local electric power producers. After re-reading these posts I got the opinion that the electric power producers in the area you refer to, Uganda, may be in need of some electrical engineers to help with the reliability of their electric power production and transmission line infrastructure. I am curious, have they mentioned any reasons why there are so many power disruptions? What is there main fuel source for electric power production; coal, petroleum, nuclear, other?

I can also imagine a system that could send a signal via higher frequency in advance of an impending blackout and warn the community. I have participated in the installation of similar systems that would warn industries of an impending time of use rate increase which would give them time to shut down the plant and save them tens of thousands of dollars in electric energy costs. The down time and loss of production is less than the time of use rate increase.

I've read that sharks have a sense of when other fish are in distress, they can use this sense to zero in on their prey. Buyer beware. PV is a sellers market. With that aside.

Seeing as how you are on grid, all be it unreliable, it can be utilized to maintain a lot of the charge to the battery bank. Great care should be taken to size it right the first time though so get someone you can trust (an electrical engineer preferably) to do a load evaluation for you if you don't feel comfortable doing yourself.
47,000 watt hours a day  or 47 kWh. I take that as a 24 hour period. In terms of amp hours of battery storage at 48 volts nominal that would be... might as well 1,000 amp hours over a 24 hour period. You say you want 3 days of ups (uniterupted power source). So 3,000 at 48 vdc nominal but you do not want the batteries to go completely dead doing this. If they are taken down to a 50% depth of discharge that would necessitate a 6,000 amphour battery bank at 48 vdc. A heavy steel flywheel generator could reduce the size of the battery bank but not the cost of the system. PV can also reduce the size of the battery bank but only during the day of course and again not the cost. A minimal size PV array can be installed and then in time more PV modules added to the array. Picking which loads you cannot absolutely do without and the amount of time you cannot do without them can reduce the size of the battery bank as well.
HUP Solar One (nwes.com) advertises a 48 volt battery bank at 1,690 amp hours at the 20 hour rate for $11,296.00 US.
The load the you stated would require at least 4 such battery banks at a 50% depth of discharge over 3 days. Not to mention shipping and handling, cable, and subsequent electrical safety equipment. Oops! I am out of time. Gota go.
 

I understand what I have been told happened to cause the increase in advertised prices of PV modules, even though I do not completely believe it all as the whole truth. It would not be the first time the truth has been stretched, or manipulated, or even the whole truth not being told purposely and letting one believe what they might. This is not an accusation aimed at anyone in particular, it is more an observation of human behavior as written or spoken over thousands of years.

PV module sales have "skyrocketed" over last few years. Who was doing the bulk of all of this purchasing? Mega corporations or Governments in proxy by way of the average homeowners? 
The trend I see is that of PV modules becoming an item that will not be affordable to the average homeowner but instead, an item for those that would have an almost inexhaustible amount of capital and, what I perceive has been happening the past few years with PV prices could merely be the proverbial "toe in the water" testing it before the big plunge into a world of..... well for lack of better terminology, the "haves" and away from the "havenots." Leaving the world to be saved by the wealthy and keeping the not so wealthy dependent on them as has been the way for thousands of years. But don't take my word for it. Pick up any history book or book from the past, or play, and you well see that this trend has repeated itself throughout human history. Why should the PV industry be any different? We will be shifting our energy dependency of a thing from one aristocracy to another. There will not be any true energy Independence for the average person until we relearn how not to be dependent on it again and with 6.5 billion humans and counting I don't see the happening ever again.

Mr. Hughes. I am not trying to convince anyone that I am right and your wrong. These are for the most part my interpretations of what I am reading and have read from reports and from what I see and have seen, being advertised and I admit a certain amount of speculation. 

The U.S. Government is placing $148,000,000 in the hands of the Solar American Initiative in order to, among other things, lower the cost of PV.
One hundred and forty-eight million dollars!
All I have seen so far (besides higher prices) are larger modules with more cells. All it takes is a basic knowledge of direct current wiring to know adding more PV cells increases wattage. My pre-teen children have a computer game that along with reading, writing, and arithmetic, teaches basic DC circuitry. I have yet to see conversion efficiencies of PV modules in production higher than 15%. For the most part they are still around 12%. Can I assume that there is still a Standard Test Condition or STC on PV cells of 1,000 watts per square meter at 25 C?
What I am seeing from my perspective has the appearance of desperation. All of this federal government money being poured into R&D causing an increase in the cost of installing an offgrid PV system which then leads to other groups asking the government to help people obtain these system with more government money in the form of incentives from state government and buyback programs from power producers. Recently the push has been for grid interactive PV systems. An attempt to increase PV sales? I just don't see the light at the end of the tunnel that you see. I don't see PV module prices coming back down or PV module quality going up. I just don't see anything to convince me of these thing.

This is the bottom line as I see it -
By the time I install a 1 kW PV array with an off grid system (hey! if were going to save the planet then lets not horse around) to utilize that power at 120 vac in my home I will have payed out somewhere close to $12,000.00 USD. Agreed?
On one good day in the summer that PV array will net me about 6 kWh. That same PV array will net me on average for a year somewhere in the neighborhood of 1,314 kWh. (Obviously this is all region and site specific and dependent on the weather but I have tried to be generous, favoring PV output.)
Now lets look at the PV industries real competitor in the USA in this conflict, the coal fired generation of electricity. That same amount of electric power over a year at $0.12 per kWh would cost me $158.00 USD. With the one time cost of installing a 100 amp service added being about $500.00 USD that figure would become $658.00 USD for the first year only.
Okay. That PV array should not cost me anything after the initial installation for at least 7 years and then I must replace the battery bank. (I could have spent more intially and gotten a battery with a 15 year life.) This could add up to about $1,000.00 USD.
13 years of PV off grid would come to $13,000.00 USD were that same 13 years on grid would be $2,554.00 USD.
Most of us have learned that the cost of an off grid PV system is comparable to a life time of on grid bills. PV output diminishes with age and utility prices go up, so they would have a tendency to cancel each other out. Lets not forget about the "many pockets" we pay from for coal fired generation that are not itemized on that monthly bill but instead show up as tax deductions from our pay checks. Difficult to figure but not impossible.
By now you might be thinking that I am pro coal fired generation. You could not be more wrong if you are. I have lived off grid for over 26 years. The first 18 without an electricity what so ever. Only in the last 8 have I harvested electricity from sunshine. MSX 77's were $400.00 USD each, a few years later Matrix 105's were $400.00 USD each, now a few years later these same size PV modules would cost me $525.00 USD or more. I don't see what was wrong with the technology of either of those first two PV modules? They are still "cranking" out the watts to this day. What is all of this R&D doing beside increasing the PV industries profit margin at Wall Street? I guess what I am really asking here, metaphorically, is how many time does the wheel have to be reinvented?

Obviously all of these figures could be challenged but if the endusers are not purchasing the product (irregardless of PV industry profits) because the price tag on the shelf is to high when compared to the established infrastructure of coal fired generation then what has the PV industry really accomplished besides higher profits? Is the PV industry really out to "save the planet" or what?
I have had a lot of people ask me about PV power and its the same everytime, the look on their faces, when they here those prices its as if Frankenstein's monster has walked up behind me! Their eyes get wide open, their chin drops, and their skin turns pale, all but the scream of terror! Then that suddenly changes into a look that can only be interpreted as "are you crazy?" but out of politeness most of them do not say that out loud instead the subject gets changed or some peripheral distraction becomes predominant.

This the bottom line as I see it.

 

I think a lot of the concern over maximizing PV module output is cost efficiency. A single 175 watt module optimized might yield an average per day over the year of 1000 watthours a day. With the cost of utilizing this power added this could cost around 1000 dollars. When compared to coal fired generation costs to the customer of 0.09 per 1000 watthours. Of course there are, more or less, unrevealed costs for coal fired generation that the customer never sees on their bill but pays all the same. This is why I think optimizing PV output over the year is very crucial.

Other times to check are the Autumnal and Vernal Equinox's (fall and spring). March 20 and Sept. 23. These two angles will be the same.
By the way, the other two dates are known as the Summer and Winter Solstice. Or the longest and shortest days and well... I guess equinox speaks for its self. Do you know about the Analemma?
On the same day of each month for a whole year push a rod,  eleven in all of equal lengths, into the ground at a point where the tip of its shadow at 12:00 noon touches the same point as the other months. If done with a little patience what you should have at the end of the year is a stretched out figure eight. This works best on flat level ground and the tops of the rods are the same height from the ground.

Oops! That should read - "number of hours of full rated output."
I miss the editing part of this forum. Geuss I will have to start reading what I type more closely.
Something else to consider id the deviation of magnetic south from true solar south if you really want to "dail in" that PV array. Set them as close as possible to true solar south on Dec. 21.
Cut a piece of 2x4 square on both ends about 8 inches long and place one end of it on a moveable flat surface. Move the surface until the 2x4 does not cast any shadow at all on Dec.21 at 12:00 noon. Thats the direction and angle you want your PV array in. If the direction is fix and the PV array is lowered for a summer Sun this will not happen until about 1:30 on June 21.

Probably just as well. It generally takes someone committed to "squeezing" as many watthours as possible from a PV array as opposed to say keeping it aesthetically pleasing for the neighbors. I mean when one considers the inflated prices of PV today, the fact that your state doesn't offer any worthwhile incentives for PV, a given amount of square footage, and last but not least available funds.
I did a comparison about 7 years ago of PV shingles and sheet as compared to PV modules and as far as watt per square footage PV modules where way above either sheets or shingles. The price difference after array mounts and such was negligible condiering the PV modules had a much higher number of hours of full rated output. How heat affects the sheet and shingle PV is another matter. Theres no where for the heat to go really and this could have a severe impact on the number of hours of full rated output. Unless your committed to saying the heck with the states lack of incentives and the utilities strangle hold on your paycheck each month, it might be better spent optimizing your homes energy efficiency.

I agree, the orientation of a PV array in relationship to our Sun is very important, concerning the number of full rated hours of output per day. Here is another site to look at where you can experiment with a lot of options.

http://rredc.nrel.gov/solar/old_data/nsrdb/redbook/atlas/

I am cynical, I know, but I do not apologize for being cynical. Cynicism to me is like a burr in your britches, it makes you want to take your pants off and get it out. Cynicism can call into action. The result of to much cynicism can even be a punch in the nose sometimes.

 Why do you suppose history is so important? Things that happened, things that people did or didn't do, 7,000 years ago, 100 years ago, just yesterday. If one listens, I mean really listen to what people are saying when we talk, one will begin to hear that we are either talking about ourselves or talking about someone else the majority of the time.

 Even though renewable energies is touted as protecting the evironment, saving the world for future generations and all of that, the renewable energies industry as a whole or as individuals is not above reproach, and yes I include myself in that statement. We are after all is said and done, only human.

Boyhowdy! You wernt kiddin. I read the advertised Specs. for both of them charge controllers you mention an theyre identical cept for one bein "optimized" for one specific brand/model PV module. Weird! Sounds like a lot a hooey to me. Snake oil salesmen kinda stuff. I wouldnta bought either one, for that reason alone.

Just out of curiosity, the PV modules your utilizin, are they that specific brand/model that the one charge controller is "optimized" for?

As for how to fix your problem without someone campin out next to the charge controller... It may be that your PV array dont have a high enough wattage for maximum efficiency. Other than that, I cant say. This sounds like a job for the BZ techies (if'n they got any that is), know what I mean Vern?

The Solar American Initiative (SAI) is a broad national program designed to encourage competition throughout the solar industry by lowering the cost of photovoltaic units and fostering innovation of new technologies.
I would say that that have not been doing to good of a job lately.
 I wonder if the U.S. government was to increase SAI's funding from $80,000,000 to say $148,000,000 would that make a difference in the price of PV module as we see them advertised at such places as the Alt-E Store?
I guess we will see...

I am going to play around with that number a little. $148,000,000. Could you build a residential PV system with as little as say $40,000? Most of you would say sure, maybe even a heck yeah! Some might say they could build a really nice off grid system with that kind of money, I know I could! Well with $148,000,000 we could build 3,700 such systems. I bet there is even a few of us, that do not require a lot, that could purchase a piece of land, build a home with an off grid PV system to power it with as little as $40,000. I have seen one acre of land go for as little as $4,000. I have read about nice homes being built for as little as $10,000. That leaves $26,000 for all the amenities and an off grid PV system. Go figure.

I don't know why, but this all reminds of that scene in Cicel B. DeMilles - the Ten Commandments, where Rameses (Yul Brynner) is "weighing" the tactics used by Moses's (Charlton Heston) in an attempt to minusulate Moses in front of Sethi (Sir Cedric Hardwicke). Anyway, my point is maybe that money should be place where it could make a bigger difference. So far I have only seen PV prices, as advertised to the general public, go up for the past four years. In the beginning, advertised PV prices were comparatively high mainly because one did not get very much for their money i.e. no frames, warranties or J-boxes and low output. That changed. The prices were relatively the same but output increased and we got frames, J-boxes and 25 year warranties for our money. Now today all we have are higher prices and we are being told that it is all because production cannot keep up with demand. Who's fault is that I wonder?
Comments welcomed.

If there is anything that our human culture on this planet Earth is not short of its cliches. Some designed to encourage someone in a time of doubt.

Sometimes one must get outside of the problem in order to "see" it from a different perspective and by doing so the solution sometimes reveals itself. Its finding the right perspective. That can be different from person to person, day to day. The duties I perform at work include troubleshooting industrial motor control circuits and a lot of the time I am coming in after several people have added and or deleted control devices and circuitry. It can be a real "rats nest" at times and most of the time I have to perform while the plant is in production. I have been told "focus on the tree not the forest." 

Fortune favors the bold.

Necessity is the father of invention.

Nothing ventured nothing gained.

"Security is mostly a superstition. It does not exist in nature, nor do the children of men as a whole experience it. Avoiding danger is no safer in the long run than outright exposure. Life is either a daring adventure, or nothing." - Helen Keller

Ok so that last on is not a cliche be it applies all the same. Then there is my favorite - "Proceed with CAUTION" - which is really an encouragement when you think about. Otherwise it would say "KEEP OUT".

"because the house will be to complicated for the normal American."

I don't know about anyone else but I find that statement very insulting.
What is the name of those financial institutions?
That really needs to be passed on to the entire RE community.

But really, what can  one  do? They (financiers) have something you want which gives them the upper hand.

I do not fully understand your last statement about trying rural but to close to town. What does that mean?

I do not know if you will find what you are looking for at this web site < www.nmpartnership.com > but it might lead you to someone who can. I glanced around this web site and read bunches of forward looking statements concerning RE and New Mexico's economy and all. It is disturbing but not suprising to me how those financial institutions in New Mexico can get away with such a backwards looking statement such as the one in your post. Next time... tell them to put that in writting then see what they have to say!

I would love to know their definition of "normal American."
I guess that would be someone who burns thousands of tons of coal everyday to produce electricity for a profit. Or floods thousands of acres of land for the same reason. Or creates thousands of pounds of nuclear waste for the same reason.
All you want to do is produce enough electrcity for your household from nature.

I have no personal experience with the Optima dry cells, only what I have read from spec. sheets and advertisements.
4 - batteries wire in parallel would make 300 amphours at 12 vdc nominal.
2 - 100 watt PV modules wired in parallel could make anywhere from 0 to 1200+ watthours a day or 0 to 100 amphours a day.
What I cannot seem to figure with any accuracy is the load in watthours over a 24 hour period. As you stated that can vary with the weather as well. So it would seem that I would have to work out averages over the period of the watering season. This is where a battery monitor that can record this information and then be retrieved by you via bandwidth would be great!
To kept it simple think only of the load in terms as coming from the batteries as if there where no PV array or charge controller. Whats the most at any one time that can be drawn from the batteries, for what period of time even if its in minutes, how many times in a 24 hours period this happens, this is all something you may have an inkling of from this watering season so far. Extrapolate from that and average out for the entire season what the watthour needs are per 24 hour period. Of course the average weather in your local is a strong factor here.
Gotago!

Opps! Two things;

1 - I should have stated that this is for true deep cycle flooded cell lead acid batteries using the advertised 20 hr. rate standard.

2 - In the example 1000 / 3 = 400 (rounded up) that can be done in another way considering kilowatthours as opposed to just watthours, 1 / 3 = 0.4 rounded up of course. Again, semantics.