complete mixed system

Wilber256 · February 2016

Hello Everyone, I am sort of new to all this and need some assistance/advice/direction please. I have a mixture of odd and end panels all 12v some have no labels but none are newer that 12 years, I propose to combine all together and charge batteries/battery and run one circuit in my home, my bedroom. I am pretty much disabled and a senior, I spend a lot of time in here watching TV (on 24-7) and some other items as well, air freshener, some CFL and or LED light(s), 5K window A/C year round, and a dorm refrig, computer charger, clock radio, and a ceiling or tower fan at times. I would like to run this circuit for as long as the DC source holds up and automatically switch to backup AC when batts are down, until recharge then auto switch back to DC, repeat, repeat. I know this is not much, but if I can stay off the grid for 3 hours in 24 to me thats better than nothing, I already have the panels, and inverter, and a 100 amp(uncertain) transfer switch, just need diodes, and batt(s) Now for the questions, How do I size the diodes for each panel not knowing some of the specs? If I have a broken glass panel that produces less than the others then the complete system will be at what the lowest value is in the array, correct? Would it be better to leave the weaker panel out ? I have a 2000 watt inverter, if I omit the window A/C and the circuit is well below the 2000 watt level do I need to have a smaller inverter? I read somewhere that one must not oversize the inverter to the load or battery, is this correct? Being on a fixed income I can't afford a new batt(s) would the marine batts at Walmart be my best bet? Do I need a charge controller between the batts and panels? Sorry for all the Q's but I would like to get these panels out of the shed and put them to use, Or would I be better just to sell these panels and start over ? Some are twenty plus years old and used, then others were purchased in between those and 10 -12 years ago new. Thanks for all the help.

Wilber256

vtmaps · February 2016

Welcome to the forum.

Battery based solar power systems will not save you any money, in fact they will cost you much more per kilowatthour than what you are paying the power company.

If you have favorable net metering laws in your location, a grid-tied system can be cost effective with a payback of just a few years. In a grid-tied system, the grid is your battery... when you have extra power you sell it to the power company.

Those marine "deep cycle" batteries at Walmart are not true deep cycle batteries... they will last about a year in real deep cycle service.

--vtMaps

South Africa · February 2016

There is another way, where you use solar power, and it may save you money over a period of time, depending on the use of the batteries.

But first reduce the load for there are needs versus wants. Wants are much more expensive to power ... but, if you live in a very hot area, aircon is not a want, it becomes a need.

And make sure the inverter can handle the aircon's startup.

If you have the parts, what I have done was to mount enough panels, yes you need a charge controller between panels and batteries, to power my load daytime with the absolute minimum batteries. Batteries are there for 2 reasons: 1) as backup in case of power failures and 2 ) to power the inverter via the solar panels.

The trick comes in by discharging the batteries as little as possible. In my case, the Depth Of Discharge is set to 5% (95% remaining) of battery capacity at which time the system switches back to utilities automatically. I do this with a Victron BMV700 battery monitors relay, switching larger 220v relays. Yes, I do need a UPS to handle the break between utilities and solar power changeover, but it can be handled without one if you can set say a 8ms changeover break between utilities and inverter power. You cannot swap instantaneously between inverter power to utilities and back. Equipment will eventually fail.

So, the less batteries AH you use, the longer they will last plus less charging is required in the mornings meaning faster switch over to using solar power daytime. I run off solar from +-8h30 till 18h30 with 5% of the batteries used early evening, in summer.

In this case it may be an option to get cheaper batteries, for they may last 3-5 years if not discharged below 20% DOD, less is better.

And it is especially good if the batteries have the ability that you can check their water levels, not the maintenance free ones, for then you can check the water levels over time.

vtmaps · February 2016

South Africa said:

The trick comes in by discharging the batteries as little as possible. In my case, the Depth Of Discharge is set to 5% (95% remaining) of battery capacity at which time the system switches back to utilities automatically.

Repeated shallow discharges are not good for lead acid batteries... it can cause lead dioxide clumping on the positive plates. Read our host's deep cycle battery FAQ to learn more:

Deep Cycle Battery FAQ:
a battery that is continually cycled 5% or less will usually not last as long as one cycled down 10%. This happens because at very shallow cycles, the Lead Dioxide tends to build up in clumps on the the positive plates rather in an even film.

--vtMaps

Wilber256 · February 2016

Thanks for the replies, I have desired solar for over 40 years, and looks like I will go to the grave with what I have or maybe a little more, My problem is MONEY, I have none, can't get any and if I could I can't pay it back, I am loaded to the brim, a lot more month than money. I wish there were financial institutions that would loan to people in my condition, I could pay back what I save each month but not much more. I am on Tennessee Valley Authority (TVA) power which is Federal Government, This year they are offering grid tie for whatever retail rate is for 20 year contract, watt per watt, penny per penny, It is a credit that is against each month's power bill, no checks or money changes hands just credit towards your next bill, which is fine, save paying the power bill or part of each month. When the allotment is filled the program ceases for the year, no guarantee they will have anything next year as the Board of Directors decide what, when and how, with the DOE approval and maybe even the President, not sure. Would dearly love to have a 5KW system installed at my home, but might as well wish for a billion dollars and then money worries are over, But I assure you I would have a system in the works before darkness falls on the day I won. I Have central A/C heatpump, the window unit is because I am very hot natured and like it about 68f whereas the rest of the family likes it 72-78f, it only runs when temp is above 70 or so and only has to cool down 2-4f as opposed to outside ambient air temp. I could survive without it, but it's nice....

Wilber256 · February 2016

OPPS!!! Forgot to add, I have a auto transfer switch from a 5kw genset, that is what I proposed to use to switch back and forth, The 5% DOD is along the lines of what I had in mind, but was thinking about 20% not over 25% but 10% sounds good aswell and my have to go the 5% to save the batts. Wonder what the Victron BMV700 cost is and best place to purchase? Thanks

Photowhit · February 2016

How many and what size panels do you have? Yes size as in 2 feet by 4 feet works also. If you don't know what voltage give us a count of the number of cells on the panel. Something like 2x4 feet with 36 cells. They cell count will give us a general idea of voltage.

I would suggest leaving out cracked panels and 32 cell panels (if you have any).

If your idea is to save money. The first plan would be to use what you've got. Money is almost always better spent reducing your load than buying solar, particularly off grid (not feeding electric back into the grid) but perhaps if you have enough, panels to make it worthwhile, some minimal additions would be okay.

If you are home all day, you might want just a minimal battery, primarily for starting loads. and run as near as possible to what the array can generate.

What type of inverter do you have? Most inexpensive inverters are modified sine wave and could create problems by shortening the life of motors and some electronics.

A TV on 24/7 can be quite a load!, what type of TV do you have? Some big screen TV's of early design can use 200 and up watts, Some new designed LED back lit designs use closer to 30 watts. I have and energy star 24" TV from @10 years that uses about 55 watts, I replaced that about 5 years ago with an energy star 39" that uses about 55 watts, today some 55" TV's use less than 40 watts!

Where do you live, that an air conditioner is run year round! I would be sure to look into how well insulated the house or room is! If it's a single room inside a larger house, be sure your door and window seals are good!

You might dump the air freshener and put in some plants, some plants are good air fresheners as will as filters and providers of oxygen....

I switched from a 2nd shift job to a 9-5 job a few years ago, being at home works pretty well for a lot of what solar does. So let us know what you've got and we'll see if we can come up with some targeted solutions!

Also read and watch some videos about basic solar setups, lots of bad info out there, but a lot of good too. You will need a charge controller to correctly charge your batteries. Solar panels tend to be fine with age, I put back in service a 35 year old panel last year to run a water pump in a hydroponic garden and she wants my other 2 for this year!

WalMart Marine batteries are a waste of money. a golf cart battery is likely the way to go, but lets see what you are starting with!

Wilber256 · February 2016

Thanks, I will see if I can dig these puppies out Sat & Sun, I will attempt to gather more details on loads, I can run a new circuit from the TV area back to the panel if need be, other areas are almost impossible to get wires in, very low attic and too close to the ground to access from underneath. Insulation in the subject area is average except under the floor, there is none and no way to add without literally taking up the floor and insulating from the top, now you are talking big money, attic is more than sufficient, walls are R13 with R3 foam board behind masonite siding, had double pane windows installed 5 years ago and got them paid off 2 years ago, But the one in my room is useless due to the window AC, I even have the central air vent closed in my room during winter, it very, very rarely gets below 69f in here even when it's in the low to mid 20's outside as we chat it's 37f outside and 71f in here due to heat produced from refrig and TV, AC is coming on and off about every 20-30 minutes, set point is 70f, I am lying here in shorts and shirtless always have on shorts and t shirt indoors 24-7-365. All panels are 12 volt, just don't know watts or amps, I know that a couple are like 10 watt, none are mono or poly panels one came off a Highway dept road sign that survived a reckless driver, it's made out of fiberglass/plastic type materials an frameless. The inverter was purchased at a Truck stop to power some small power tools when I was out on the road working, It's never been used, I had a 700 watt I used instead. We reside in NE Mississippi and it's tornado season and would like to get something ready for power outage to watch local TV weather. I will test open voltage on them with my Fluke DMM in full sun, measure dimensions, and hope to take pics if they are allowed to be posted, and I can figure out how to. Thanks for the batt info, I am heading there as soon as I make this post. Hold on I remembered the inverter is here in my room....I stand corrected, it's 1000w cont. 2000w peak, Cobra Highgear brand, 4 30a fuses in back, number 4 welding cables with very heavy clamps, Model HG PI 1000, S/N 205019361, Cobra Electronics, Chicago IL. I will let you guess where it's made, bummer....Status monitor with LED readout and bar graph for batt % 0-50-100% has 2 120v 3 prong receptacles and 1 120v recp. w/o ground, cooling fan also. I will hook it up to my truck and see what it will do, its 10-12 years old, dirty, rusty but never been used.

Thanks All

South Africa · February 2016

Wilbur, start here: https://www.victronenergy.com/panel-systems-remote-monitoring/bmv-700
They are a wee bit expensive but sometimes you can get a 2nd hand BMV600, for next to nothing. The SOC and relay contained in them, is what I was always after.

VTMAPS, interesting. I did not know of potential lead dioxide clumping.

At least there are some suggestions here now that Wilber can start working from. If I was close, I would have donated a few unused parts to him, for as with most solar experimenters, we always have parts we never use.

Any case, leisure batteries are more suitable for UPS'es, they are left in fully charged state most of the time until power is needed once in a while, therefor my suggestion. So Wilber going to 20% should be perfect I recon, for as Photowit said: "If you are home all day, you might want just a minimal battery, primarily for starting loads. and run as near as possible to what the array can generate."

Ps. I think I am going to start using my T105RE's on Friday and Sat evenings up to 50% DOD, for Sat and Sun mornings most computers are off, wasted power.

Wilber256 · February 2016

Would one still need a charge controller with the Victron, or does it take care of all battery duties except invert ?

South Africa · February 2016

The Victron BMV monitor is only to measure the battery SOC so that you can use less and cheaper batteries, to not drain them beyond say 20% DOD. you do this by using the built in relay of the BMV that reads the SOC and based on your setting, it's relay triggers a AC relay to switch the load from inverter back to utilities.

You need a charge controller between the panels and the batteries.

vtmaps · February 2016

South Africa said:

The Victron BMV monitor is only to measure the battery SOC

The battery monitor does NOT measure the battery SOC.

A battery monitor is often compared to the gas gauge in your car, but that is not a good analogy. The gas gauge in your car actually measures the level of gas in your tank. A battery monitor doesn't measure the level of anything. It is more like the odometer in your car. The odometer counts miles and the battery monitor counts ampHours.

Suppose you have a car that gets about 25 mpg and has a 15 gallon gas tank. Suppose also that your gas gauge does not work. What do you do? You use your odometer. For example: After a fill up you drive 150 miles and you expect that you have used 6 gallons and have 9 gallons remaining in your tank.

If you fill up the tank again you can, as above, use your odometer to estimate your gallons remaining.

But what if you do not completely fill your tank. For example, starting from a full tank you drive 150 miles and then you add 3 gallons to your tank and then drive 100 miles and then add 4 gallons to your tank and drive 150 miles and then add 5 gallons to your tank and drive 100 miles. At this point you estimate that you have 7 gallons remaining in your tank, but that estimate is not too accurate because your mileage is not exactly 25 mpg. The only time you know exactly how much gas is in your tank is when you have just filled it up (or when you run out of gas).

So it is with your battery monitor. The only time it is exactly accurate is when you fully charge your batteries and reset the battery monitor to read 100% full. It can be very accurate counting the amphours in and out of the battery, but it can only estimate the state of charge based on what you tell it of the battery capacity and of the battery efficiency. And remember, capacity and efficiency depend on temperature and vary over the life of the battery.

When a battery is cold or old, it has reduced capacity... if you draw 50 ah from a 200 ah battery, the battery monitor will say "75% SOC". But if your battery has an actual capacity of 100 ah and the battery monitor doesn't know that, it will still say "75% SOC" when your actual SOC is 50%.

By the way, you need to tell the battery monitor the efficiency of your battery... otherwise it can read 100% (by counting amps into the battery) before the battery is fully charged.

--vtMaps

Wilber256 · February 2016

Appears to me the Victron is a tool of pleasure as opposed to need, If the data is known to program in then great, if not why even have it to begin with other that to get a broad idea of what you may have. I believe i had rather have a decent charge controller that will drop out at setpoint and engage at a setpoint, or one that will switch and route excess power made into say a 12v water heater element. I would like to add a wind gen to the setup as well, although we don't really have enough wind in my area to justify the expense they say, but during winter and especially spring we have a lot of wind almost daily from early AM to about dark. I suspect/expect an above normal production of watts made by both systems combined during these times if I reduce my load to have power longer, at that point that power will have to go somewhere, or not be made by the wind gen, then why have it if not going to utilize the power. maybe just add another batt is the best solution to the problem, but that's money I don't have. If I can purchase either on Ebay or Amazon i have accounts with these guy's or somewhere that uses PayPal as I have an account with them and that's how I pay for Ebay items, all monthly payments. Update on the inverter, I hooked it to my Truck batt, it will arc when attaching clamps more so if in the on position, but the cooling fan will jump just a fraction and stop and the LED digits flash on and back off within 1/2 a second the . remains on but everything else is off. I have a 40 watt fan running and set the inverter in the 63f (shade) ambient sunshine to try to heat it up to see if fan will come on. so far nothing, may need more load to heat it up internally. I have the measurements on the panels, If someone will instruct me on how to post pics, I will do so if not I will just post the information.

zoneblue · February 2016

very rarely gets below 69f in here even when it's in the low to mid 20's outside as we chat it's 37f outside and 71f in here due to heat produced from refrig and TV, AC is coming on and off about every 20-30 minutes, set point is 70f, I am lying here in shorts and shirtless always have on shorts and t shirt indoors 24-7-365.

You americans are softys, got used to your central heating. The average indoor temperature in NZ is something like 14-16 degrees celciius (60F). If you want to save some money, then reducing the thermostat to 60, and putting on a layer or two is going to cost you the grand total of...exactly nothing.

Quite tricky to cut heating costs in the wintery north though. NZ power bills (depsite really high grid charges) are a good deal less than yours. How many kWh do you use each day? NZ average is 20kWh/d, the US is 32kWh/d, which is the second highest in the world. See http://shrinkthatfootprint.com/average-household-electricity-consumption

Solar can however be a neat project, something to keep the hands and mind busy. So if you can locate a real good deal on a battery, then you might be able to get a system going with some surgical additions, and careful planning.

As far as new batterys go GC2s are as cheap as they get. But you may not have a place to store them, and you just might be able to, with some research locate some ex telco AGMs, that while not an ideal battery, can be made to work, and can be picked up dirt cheap. Theres a few here who have done it, The key for you is keeping the cost down.

Wilber256 · February 2016

Zoneblue, If I had my way that is what would happen here, but I have a housefull of people from wife of 40 years down to next to youngest Grandson (31/2 years old) that stay's here more than at his home, oldest Daughter (38) and her Daughter (14) have moved out from home and in with us, 22 YO grandson has lived with us his whole life, and youngest Daughter, husband and 3 week old baby are here as we chat. So given the numbers: 1 older lady that is very cold natured, and others that aren't far behind, you are correct, we are spoiled, and to a lot more than central AC/heat. Not the first person in this household is employed, we survive on our limited monthly checks, I am disabled, Wife is retired, Oldest daughter has Fibromyalgia really bad and has not worked in 11/2 years for more than a week or two, She tries but just can't cut the pain, She receives no Government benefits as the S.S. people say she is too young to be drawing (no income has a lot to do with them being out of her home ) 22 YO Grandson has no job, stays up all night, sleeps all day, don't even have a driver's license, has no desire to get one, Gets very mad if asked to help around the place, pick up limbs, help mow the grass, take out the trash, ect. ect. ect. He better be glad that Ma-Ma is still alive. This is why I would love to offset my power bill by a few dollars, I am the only person here that tries to conserve others leave lights, ceiling fans on while out of their rooms, it just burns my butt up to pay for something that no one is getting any benefit from. I already have some junky panels and a 1000w inverter, $250 dollars I have from selling my coins, and another item or two, If I could sell more of this HVACR/Electrical/Plumbing tools and parts/materials I no longer need I could have more to work with but everyone wants me to give things to them, I am very low on prices but still people want something for nothing....

Photowhit · February 2016

Don't go out and buy anything, until you/we figure out what you have!

I think you might impose an 'unemployment policy', strange as it seems. After 10 years at a job that largely went south, first cut back, then disappeared. I found my self on unemployment 3-4 years ago. I had no bills and was comfortable collecting unemployment, but they have this nasty requirement that you must record 3 contacts that you made for employment each week. I really was sorta milking the system, but during those required contacts I was first offered a part time job, that I could reasonably refuse (35 miles from home) then a full time job, which I accepted. If they are there and able-bodied requiring them to look for work and/or do a few hours of work around the house each week is more than fair. It will make them better people!

Wilber256 · February 2016

Photowhit, I could not agree more, That lazy a** Grandson will be piled up in bed while his going on 67 Ma-Ma will be out in the heat of Mississippi summers push mowing a 25 degree angled bank 35 ft tall and 250 ft long, She refuses to ask him to assist until i raise pure H*** then it takes him 30-45 min. to get dressed and gather his music to listen to before coming out to help, then they split the rest of what's left. She absolutely refuses to let him use the weed eater in fear of her plants, bushes and flowers, so at 5' tall she does it all, including mowing about 4-41/2 acres on the Exmark ZTR, she is afraid he may run over something or wind up in our pond. I am of 0% help as my back barely allows me to walk over about 50 ft without resting, then i can't stand for over 5-10 min max, sit for about 15-20 unless I am where I can slought. it's really depressing with all of this as I was one hell of a man until I really screwed up my back then it was discovered that I had some hereditary problems there also. I have lost all muscle mass lying in bed since my injury on 5/23/2005 and have no strength to help do anything requiring physical strength or endurance. He would not stop and pick up a pile of dog crap in his pathway, he would just step over it until ask to 8-10 times, then told to with raised voice twice or three times, i don't understand these younger people these days, don't care if the sun don't shine unless it's an inconvenience to them. AArrrr....Can the attach image/file be used to post pics? If so is there a limit per post? I can take my wife's Ipad and take pics of this stuff for y'all to see, may help in making decisions on what needs to be done. Thanks

zoneblue · February 2016

Sounds like, you dont need heating, just insulate the place and all the occupants will heat it right up at 150W per person

Had this lecturer once that built a house in the UK, that was heated by the occupants, some limited solar gain (tiny heritage windows), and the two pets. Had like 500m insulation and a HVAC heat recovery system.

Kinda major off topic, but tough love man, a 22 year old needs to be paying full market board. Thatll make him find a job right smart. Give him a window to sort it. Nagging as you found tends to be ineffective.

Wilber256 · February 2016

I recall back 30 + years ago reading about a home in WS or ND somewhere up in the cold US where they had built a home in the side of either a large hill or small mountain with very, very limited exposure to the ambient temps, just a walkway/tunnel into the home. They were heating it with the light they used to see by and body heat of the occupants, they would on occasion have to exhaust out the heat and replace it with cold outdoor air to cool it down to enjoyable temps. Of Course they had to make fresh air exchanges to bring in fresh air and vent out the bad. It was a large home like 3-4 bedrooms 2 bath large LR and kitchen/dining. Man did I envy these people, I think it was Popular Mech Mag. is where I read about it along with several other homes that had done the same. Some of you guy's in this cold area may be familiar with the procedures they used. I have always wanted to be inside of a hill to help with heating and cooling and hide from those bad storms with tornadoes, just leave the front open, maybe 20-30 ft to have windows and see outside. I do also recall back in the 70's when things got tough with energy, people were building semi-underground, just covering up their homes with earth, helped out tremendously.

Blindowl1234 · February 2016

Wilber, I'm in Ohio and there's a house like that near me. You can't see much of it from the road, just the windows in the front. Looks neat and I'm sure it works well for them year round.

Wilber256 · February 2016

Alright, Here is the dope on the 7 panels that I have: All electrical DMM that I own have clamp style amp probes, none inline to measure short circuit amps, some have semi legible labels, some have nothing. All are at least 12-13 years old and some (arco) are probably 30 as they were purchased used from a guy that was redoing his off grid system about 15 years ago. The 3 Arcos, per the web are between 32-45 watts, depending on who you believe, I guess them to be sold as 40 watt panels when new.

1. MFG. ?
Model?
Volts: 22.3
Watts:?
Amps:?
18.5"x12.5"
Made in China (MIC)
Thin film panel?
Condition: New, but old
Notes: Has batt clamps they plug into a built on receptacle. may have used in past to keep charge on auto, mostly stored in shed.

2. MFG.?
Model: MODSP30
Serial: SP1000309342
Volts: 21.9
Watts: 30
Amps:?
31.75"x13.50"
Made in: Overseas
Thin film?
Condition: New, but old

3. Phoenix or maybe Intersolar LTD?
Model: B107W ?
Volts: 22.5
Watts:12
Amps:?
12.25"x36.25"
Made in:
Condition: New, 15-20 years old?
Notes:
: B107W ?
Volts: 22.5
Watts:12
Amps:?
12.25"x36.25"
Made in: United Kingdom
Thin film Silicon
Condition: New, 15-20 years old?
Notes: Had to remove connector to get any reading

4. MFG: Uni-Solar
Model: US-64
Serial: US-64 114870
Volts: 23.1
Watts: 64
Amps: Max=3.8 Short=4.8
29"x53.5"
Made in MI.USA/Mexico
Cells: 2 rows of 11
Condition: Used, 13 years old, minor damage
Notes: Made of plastic/fiberglass? Frame less, Has J box, came from highway dept road sign. WWW.uni-solar.com

5. MFG: Arco Solar
Carrizo Solar Corp
Model: M51
Serial: 119622
Volts: 20.4
Watts:?
Amps:?
12"x48"
Made in CA. USA.
Cells: 2 rows of 12, 1 row of 11 (center)
Condition: Used, 30 + years old
Notes: Has Diode connected to + in J box.

6. MFG: Arco Solar
Carrizo Solar Corp.
Model: M51
Serial: 120223
Volts: 19.9
Watts:?
Amps:?
12"x48"
Made in CA USA.
Cells: 2 rows of 12, 1 row of 11 (center)
Condition: Used 30 + years old, SHATTERED GLASS
Notes: SHATTERED GLASS, Has diode connected to positive (+) in J box

7. MFG: Arco Solar
Carrizo Solar Corp.
Model: M51
Serial: 119606
Volts: 19.7
Watts:?
Amps:?
12"x48"
Made in CA. USA.
Cells: 2 rows of 12, 1 row of 11 (center)
Condition: Used 30 + years old
Notes: Has diode connected to + in J box.

BB. · February 2016

Be very careful about "no heat" and insulating/sealing the home up. People (and cooking, etc.) gives off quite a bit of humidity. It is very easy to cause high humidity and mold in the home. And that can be a real health risk--As well as expensive damage to repair.

More or less, get a cheap weather station or indoor humidity meter and monitor what goes on in the home. Over 60% relatively humidity for 3+ straight days, and you have the starting of a good mold/mildew farm.

There are other ways of controlling humidity (dehumidifier, heat recovery ventilator, etc.).

Don't trade one solution (lowering heating bills) with other expenses (running a dehumidifier) or worse, damaging your home and health (mold).

-Bill

Wilber256 · February 2016

Thanks BB, I don't have a high humidity problem, I have a low humidity problem as I write this it's 75F/41% outside and 72F/39% in my room. We have 3 humidifiers in my home set at 45% and they never turn go off, They will run out of water on occasion. Now summer the AC takes care of the problem but heatpump/strips (when needed) along with a propane heater if colder the 20-25F outside is used, so it's dry in here. At this point in time my objective is to utilize 7 PV panels along with a 2000 watt inverter that I have on hand, I would like to generate enough power to offset some of my grid consumption, won't be but a very little but every watt counts. I would like to have enough storage to run a TV and Satellite receiver if the power is out so to keep up with the weather conditions, maybe run a couple of LED lights to see how to get about or whatever reason. I have been lusting after a Acurite 5 in 1 system for quite sometime, They had them on sale lately but I decided to wait and spend what little I have on this PV project. I have a 50 ft Rhom tower that I propose to stand at the east gable of my home with a TV and antenna and Cell booster antenna also a wind gen on top, but money, money, money. I have the tower and a homemade wing gen from ametek DC motor/gen with 25 ft pole that has been lying under pine trees for 11 + years covered with pine straw that was what was suppose to be my little wind gen. and go on the top sticking up above the top about 10 ft. Chances are it will never move, but I have a couple more of those motors i can replace it with, Just hope the store bought blades are not bent or ruined. Anyway that's where I wanted to put the weather station to hope to get up at least even with these two big tall oak's. But PV first, then maybe everything else, I wanted to mount these 7 panels on a stick of 10ft metal 11/2" pipe and rig up a east to west tracker to turn the pipe and mount their rack on/thur the tower.

Wilber256 · March 2016

Blindowl1234, That's like the ones I was talking about, covered everywhere except the front or some just a few feet across the front for the door and sometimes a window, but most the front is open and the rest is under 4+ feet of earth, graded to be able to easily run mowing equipment, Some have a garden on top. I would like to have a carport on top with stairs down into the home, my reason is two fold, 1. extra exit in case of fire or other emergency. 2. If done correctly the stairwell come become a chimney to exchange stale air with fresh outside air.

Blindowl1234 · March 2016

Wilber256 If it didn't sit so far back off the road I'd get a picture for you. It looks nice from the outside. There's also two round houses near my house that were built in the 70's. I knew the guy that did the drywall which he said was fun to do in a round house. I sympathize with you on trying to do solar on a limited budget. Same story here too. I've got two part time jobs and my wife is disabled. I've got a 100 watt panel and a 25 watt panel with a 5 year old car battery for now. It runs 16 various landscape lights in our yard, and on our porch and deck out here in the country. I figure the total wattage of the lights to be just over 20 watts. Some of the lighting is 12 volt and some is 5 volt. A decent day of sun and I've got 10 hours of lights at night. My goal this summer is a deep cycle battery or two, and maybe another panel for more lights. I dream of living off grid which won't happen due to the cost and the wife factor lol. I'm envious of the systems some of these guys have, but I'm tickled to have what I've got and it works. Hang in there and remember there's nothing wrong with trying to save a dime here and a dime there. Those dimes make dollars too.

BB. · March 2016

Don't bother with the Shattered panel(s). They will not last, are not repairable, and potentially a fire hazard.

Many of your panels are 12 watt (to maybe 20-40 watt maximum). By time you wire those panels up--You have a lot more money/time spent in mounting and wiring. Plus, the problem of maintenance (failed wiring connections from weather/time, etc.).

One 140 Watt panel (which is relatively small these days) is the equivalent of ~10 to 12 of the small 12 watt panels you are looking at using. 1/10th the wiring, 1/10 the mounting, 1/10 the possible wiring issues/costs.

Look around (Craig's List, etc.) and see if you can find some larger panels at $1 per watt or less. $1-$2 per watt + shipping is the rough price for panels these days.

And, depending on what panels you find (Vmp~18 volts vs Vmp~30 volts or other)--You may have to change charge controllers (PWM vs MPPT) and/or battery bank voltage for optimum system design.

But--Be careful here. We are putting the cart before the horse. You need to design a "balanced system" that will support your loads. If the system is too small--It simply will not give you the power you need. And if too large, it is a waste of money.

In the end, if you are trying to save money--Start with extreme conservation in your home. It is almost always cheaper to conserve power than to generate it. And for off grid power systems, it is not unusual for the all up costs of off grid power to cost you 5-10x the cost of utility power. Batteries that last 5-8 years, electronics (inverters, charge controllers) that need replacing every 10+ years, etc... It all adds up.

For pure off grid homes--It is possible to get down towards 3.3 kWH per day (100 kWH) per month and live a near normal electric life (use propane, wood, etc. for heating/cooking/hot water--And/or solar thermal for hot water/heating). That may be a $20 per month electric bill.

If you still want solar/battery backup to ride out power failures (weather, accidents take out power pole, etc.), solar+genset backup can still make sense--But this is usually a secondary reason. And if your outages are relatively rare--A backup genset can be a lower cost solution. And you still need to analyze your emergency loads. Again, balance the power source to your power needs.

-Bill

Wilber256 · March 2016

Blindowl1234, You could always act as if you are selling Avon/Tupperware/Stanley Home products/etc. or just ask for directions, maybe to your own house lol, There are several round fiberglass dome homes scattered within a 20 mile radius of my home, neve saw the advantage execpt for wind resistance, I would take one of those and bury it in the ground, One has a full house under it, more like a livable basement I suppose. Sounds like you are off to a good start with your PV savings, just makes me feel good knowing i am off the grid just a little, and not having to jump and croak every time the Power Company says jump. I know 99% of my power CO. guys, I was an Electrician/HVACR Tech/Plumber before my injury so I have battled with many of them at many different times in the past 40+ years, I don't get along with them, kind of like the enemy, and their way or no way even if its not practical and different from the National Electrical Code, just wish I could drive by the office and wave at the people with a jerk grin on my face, but time is short for me and money is even shorter....I hope.....

Wilber256 · March 2016

Thanks BB, I purchased a DMM with inline current testing abilities from The Waltons today just to check short circuit amps on this junk. I may just break up the group for other purposes e.g. DC water pump, semi portable power at the pond, etc. 20-25 years ago this junk was a lot more valuable than it is today, as you stated some panels are $1 a watt. I am going to check my consumption in my room to see what is what, and have a dedicated circuit off these just for power outages which are common here during tornado season FEB-JUNE and sometimes in fall and winter if it warms up then a cold front moves in, bang!!! Wish i could find some good panels for $1 I could maybe get a 100 watts and controller for a couple of hundred, that's what I have accumulated after sell (giving away) my coins and plastic paddle boat.

Blindowl1234 · March 2016

Wilber256 said:

Blindowl1234, You could always act as if you are selling Avon/Tupperware/Stanley Home products/etc. or just ask for directions, maybe to your own house lol, There are several round fiberglass dome homes scattered within a 20 mile radius of my home, neve saw the advantage execpt for wind resistance, I would take one of those and bury it in the ground, One has a full house under it, more like a livable basement I suppose. Sounds like you are off to a good start with your PV savings, just makes me feel good knowing i am off the grid just a little, and not having to jump and croak every time the Power Company says jump. I know 99% of my power CO. guys, I was an Electrician/HVACR Tech/Plumber before my injury so I have battled with many of them at many different times in the past 40+ years, I don't get along with them, kind of like the enemy, and their way or no way even if its not practical and different from the National Electrical Code, just wish I could drive by the office and wave at the people with a jerk grin on my face, but time is short for me and money is even shorter....I hope.....

I don't know but out here if I pulled in their driveway I might get met with a suspicious homeowner and a 22 lol. My late father was a union electrician with G.E. for 39 years so needless to say I miss his help with all this solar stuff. I think he would've loved it since he could do all the math in his head too. I sold HVAC stuff for 20 years so I'm familiar with that business too. Seriously though I feel good tinkering with stuff and just knowing I'm saving a dollar here and there, puts a smile on my face. Our problem was we had all these solar lights that ran off panels about the size of a Reader's Digest. The panels put out about 4.5 volts and would eventually die. In winter with 3 of them on the roof there wasn't anyway to get the snow off them. I've almost tied all these lights to the 100 watt panel and all them come on for 10 hours at night, which is what we wanted. Easier to clean off in the snow too lol.

Photowhit · March 2016

Wilber, I don't think there is enough there to suggest you continue building a system, if your goal is saving money.

If every thing that isn't cracked worked you might have;

1 amorphous pnel with likely a 10 watt output
2. amophous panel with a 20 watt output
I'm guessing these are actually amophous panels, voltage is too low to be thin film panels (generally)
3. amorphous panel with a 12 watt output
4. US-64 a good panel, but since they are not glass tend to cloud up and produce less over time.
5. Arco m51 about a 50 watt panel?
6. M51 shattered glass
7 M51 about a 50watt output.

I wouldn't use the shattered glass panel, I would be more worried about it it losing a connection than shorting out, but it is likely a headache waiting to happen.

The M51's are a bit of history You state 'carrizo' panels so they were likely made for a large power plant in Carrizo valley(?) that was never made after Arco sold out to Seimens(?) (Needs some serious fact checking here!)

So you have what might be 200watts of array if everything was working fine and newish. More likely they have reduced 1/2-1% per year and the plastic coated UniSolar panel at about half of capacity. So 120-150 watts of array possible, when in perfect conditions. Maybe 75% of that in normal conditions. say 100 watts, a nice round number to work with.

On an average day you will have 4 hours of sunlight (you can check charts of solar isolation to find closer to your area) so might generate 400watt hours of electric, or about 4 cents. Thaat's a bit less than $15 a year. Batteries, a reaccuring cost would run a minimum of $100 every 5 years. And we haven't talked about fusing or a charge controller or other expenses.

If you would like to play, understanding that you will likely spend more than it returns. I know where an inexpensive charge controller can be had that would handle the 3 good larger panels. and you might hook up a throw-away car battery and try to run a few things directly off 12 volt during the day. Maybe even a couple 12 volt fans like the 0'2Cool fans, which might run off a single panel directly....

Wilber256 · March 2016

Thanks Photowit, I was guessing about 150 watts at the most, I now have a DMM to check current, will do as soon as the rain and clouds move out. Strange, the shattered panel produces the same voltage (open) as the other two Arco, also the glass is smooth to the touch, if you close your eyes I don't believe you can tell its broken, strange. I assume the damage was made from UPS playing soccer with the box while in transit, it was several months before opening the box after receiving them. I have some preliminary figures from my kill-a-watt meter. TV=110w, Air cleaner= 15L/25M/50H watts, normally run it on Low/15W not needed during power failure, Fan 50w, not used during cooler/cold weather. Refrig, 0w until door opens, then 10w. Or compressor comes on, startup, 140w, running 93-110 after first 2-3 minutes 105w, after 8-10 minutes 93w and holding.in that range so far 91-93w, not needed during power failure unless out for longer period. Will post Satellite and other TV for power outage use in next few days, I have a Dr. Appointment for shots in my spine Thu. probably will be bedridden for 3-4 days will continue afterwards. Frig is down to 90 at last checking.

complete mixed system

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