I'm going off grid!!!

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S.G.C.

New Friend
Neighbor
Joined
Jun 29, 2019
Messages
2
Location
Ca soon Or.
SO yes I'm new here. Not new to the concept, or living off the grid when someone else had the controls of designated power source, BUT!!! I am building a good robust Battery Bank for a general two-person house. My thoughts are before I go completely "Natural" power. I am going to use a SUNGOLDPOWER 2000W Peak 6000W Pure Sine Wave Power Inverter DC 24V AC 110V With Battery AC Charger LCD Display Low-Frequency Solar Converter BTS+Remote Control AC Priority Battery Priority Switch. I am going to conjoin my back-up with a Duel-Fuel generator. This will be connected to an LP tank on the property. The batteries in line will be, Renogy RNG-BATT-GEL12-200, Gel Battery 12V 200Ah. My biggest question is how many Batteries will I need, in series, to complete the task? I have gone a bit over on KiloWatts per month. This way until I get the Sun, Water, Wind resource harnessed I will have plenty back up. I am looking at roughly 3200 kilowatts per month. Is my calculation correct in thinking that two of the above-stated batteries are sufficient? I'm not sure, The AH is plenty, But truly will only two deep cycle batteries perform this task? Seems not enough, perhaps I'm looking at this backwards........

Cheers,
Curious
 
Welcome!
You have 12 V batteries and want 24V. You connect 2 batteries in series to accomplish this. You can then connect your pairs in parallel. This is how I made my system. I connected eight 6V batteries in series for my 48V system and then connected the two 48V banks in parallel.
 
To answer the question of "how much is enough?" requires you to calculate the watt hours needed and the watt hours you can recharge.
100 batteries are no good if you can't keep them charged and 40 Kw of panels is of little value if you can't store it. Then you have to figure out how much you actually have in mid winter and the longest period that you will go without making power. Here in the valley we have two weeks of heavy fog twice a year. There is no wind and very little sun so having the battery storage for two weeks is necessary if you want to be off the grid or you need to plan alternatives to wind and solar for those periods. My generator uses about two gallons of fuel a day to provide minimal power for the home and charge the batteries for use at night. That requires almost 30 gallons for a two week period so 60 gallons per year for the two 2 week power shortages. If you have a smaller home that is super insulated, with a geo-grid for heating and cooling you may have less power demands. If you are willing to live differently and have the acreage with trees for fire to heat and cook You can live with less power.
I have lived both ways and I would rather not have to cut and split wood to stay warm. (one chord of wood per acre/year)
 
Going off the grid can take some planning and number crunching. I have a book written and published on Amazon (https://www.amazon.com/Build-Low-Bu...ven+gregersen&qid=1564323387&s=gateway&sr=8-6) that will give you all the details you need.

Basically, you need to figure up the actual expected electrical use and your peak draw. You cannot even begin to set up an adequate off-grid power system unless you know how much electricity you need on a daily basis.

Unless you have some big draw items your inverter/charger sounds adequate.

Generally speaking your battery bank should be sufficient to power everything for a minimum of three days without any solar power (five days are better). This should ensure that you don't excessively discharge your batteries and run them in a discharged condition for long periods of time. I cannot emphasize this enough! Running the batteries in a constantly low state of charge will shorten their lifespan considerably.

Your solar panels need to produce enough power to fully recharge your batteries from the amount drawn the previous night while the sun was down and power your home during the day (while recharging the batteries) on an average day of sunshine.

A general test is that if your battery bank is excessively discharged when you get up in the morning then you need more batteries to store more power. If your battery bank is not fully recharged by the time the sun sets then you need more solar panels.

If you have wind available you can help your system by supplementing the solar panels with a wind turbine. The nice thing about a wind turbine is that it will add power during the night and on cloudy and/or stormy days. However even in high wind areas I would still rely mostly on solar and use the wind as a bonus power source. I've found the sun to be consistently more reliable than the wind.

We have a modest (1,000 watt) solar power system at our cabin that produces enough power to run an (12 cu. ft.) electric refrigerator. We have a 500 (plus) watt system on our motorhome that runs a small electric fridge (in Nevada/Arizona) and powers the rest of the motorhome. We just purchased a 5th wheel last year and we have about 320 watts of solar power on it and we have lots of extra power but it has a propane fridge so the only thing we power are the light (which are LED) and our electronic devices such as cell phones, tablets, laptop computer, DVD player, etc. We have a camper van that has a 60 watt panel and runs the lights and electronic devices (propane fridge).

I run everything on 12 volts simply because I can recharge a lot of electronic devices on a 12 volt system, therefore bypassing the inverter. I also use 12 volt storage batteries. It's more for simplicity than efficiency. Higher voltage systems are more efficient if that's the way you want to go.

We are very frugal regarding electrical needs so we don't use a lot of electricity even in our cabin. Once you begin crunching numbers you'll see that you will save a lot of money on solar and batteries if you can cut back on electrical needs. (It's all in the book.)
 
I run about 5 hours a day on mostly solar, one refrigerator, a small chest freezer, up to 4 ceiling fans, LED lights and other things on outlets and I can run another bigger refrigerator and more outlets just by flipping some breakers. My solar array is 1,560 watts, the battery bank provides 1,025 amp hours and the inverter/charger is a Magnum Energy 4,000 watt pure sinewave unit, 24 VDC in and 120/240 out, since I don't use solar for water heating, any electric cooking other than a 200 watt slow cooker and no clothes dryer, this solar system does a great job within it's design capabilities. I always tell people that are thinking of going solar to think small, to understand the minimum they can live with, because if you get carried away with trying to run everything in the home with a solar system, it will get very expensive. Even I don't expect to be running all the refrigerators and freezer for a very long time under a SHTF situation, we'll switch over to freeze dried and dehydrated foods as soon as we use all the foods in the fridges and freezers. There is no sure thing as constant sun availability, especially in winter months, the best defense for less solar availability days is to have high cell count solar panels that give you far more voltage than you need to charge your battery banks with and to use MPPT type solar controllers that can make use of the high DC voltages to charge your batteries even on cloudy days. Full sun my solar array puts out nearly 80 volts so with far less than 1/2 that output, the batteries will still get a charge, even later in the day when the sun is no longer directly hitting the solar panels, I've seen enough voltage to produce charging, especially when the controller is in the float charge stage. I am totally sold on MPPT type solar controllers and high output solar panels.
 
I agree on the MPPT controllers. They are great at milking every drop of solar energy from your panels.

The nice thing is that solar panels and accessories have come down so far in price. My wife was reviewing her journals over the first couple of years we lived off grid. We paid $600 for the first 110 watt solar panel we purchased. Now panels are easy to find at a dollar per watt price.

We live in NW MT. We just shut off the fridge around the end of November and it stays off until it warms up again in the spring. Our available daylight in winter is very low.
 
I am in the market for a charge controller and an inverter. I would appreciate recommendations as to brand, model, and a good company to buy from. I want around an 8K 120/240 inverter for a 48V battery bank. Right now I have about 4K worth of panels but plan to increase as resources allow. I have two banks of 8 6V 225Ah batteries. I can switch it manually but an automatic system would be a real bonus.

Heat and cooking are natural gas. I have 2 freezers, 2 refers, 2 CPAP machines, and a deep well pump. In a SHTF there won't be any TV to worry about, my coffee pot has an insulated carafe so only uses electricity to boil the water, and the lighting is LED. Isolating any unnecessary circuits is of little benefit.
 
The Magnum Energy inverter/charger I use is for a 24 volt system but they do make one for 48 volt model that's 4,400 watt that is stackable to 17.6 kw, with two it will give you 8,800 watts 120/240 volts, you have to have an ME-RTR router to tie them together, I bought this router just in case I wanted to add another inverter to double our wattage. These inverters have a built in transfer switch and switch over so fast that there is only a slight blink in any lights that are on, even electronic clocks stay on time. Your deep well pump is the largest starting draw on wattage used and a single 4,400 watt inverter would more than likely take care of that as they have a 8,500 watt 5 second surge power capability. Check out donrowe.com , they have a very large brand list to choose from, I bought Magnum Energy because they are heavy duty transformer based pure sine wave inverters which are very kind to things that have electronic controls and are less likely to overheat sinewave sensitive motors. There are also many good makes of charge controllers, I happened to get a Morningstar MPPT-60 solar controller, they are good for up to 150 volts DC input and can be set up for charging 12, 24, 36 and 48 VDC battery systems, at the 48 volt setting they are good for 4,000 watts of array power, many can be tied together to make even charging of multiple battery banks by using a router to connect the controllers.
 
I run about 5 hours a day on mostly solar, one refrigerator, a small chest freezer, up to 4 ceiling fans, LED lights and other things on outlets and I can run another bigger refrigerator and more outlets just by flipping some breakers. My solar array is 1,560 watts, the battery bank provides 1,025 amp hours and the inverter/charger is a Magnum Energy 4,000 watt pure sinewave unit, 24 VDC in and 120/240 out, since I don't use solar for water heating, any electric cooking other than a 200 watt slow cooker and no clothes dryer, this solar system does a great job within it's design capabilities. I always tell people that are thinking of going solar to think small, to understand the minimum they can live with, because if you get carried away with trying to run everything in the home with a solar system, it will get very expensive. Even I don't expect to be running all the refrigerators and freezer for a very long time under a SHTF situation, we'll switch over to freeze dried and dehydrated foods as soon as we use all the foods in the fridges and freezers. There is no sure thing as constant sun availability, especially in winter months, the best defense for less solar availability days is to have high cell count solar panels that give you far more voltage than you need to charge your battery banks with and to use MPPT type solar controllers that can make use of the high DC voltages to charge your batteries even on cloudy days. Full sun my solar array puts out nearly 80 volts so with far less than 1/2 that output, the batteries will still get a charge, even later in the day when the sun is no longer directly hitting the solar panels, I've seen enough voltage to produce charging, especially when the controller is in the float charge stage. I am totally sold on MPPT type solar controllers and high output solar panels.

This just reminded me to put a clothes line in the greenhouse. it gets really hot in there in the summer and warm in the winter.
The solar you and others here helped us pick out has 580 watt mono panels.
All that is still packed away till we can decide where to put it up.
 
This just reminded me to put a clothes line in the greenhouse. it gets really hot in there in the summer and warm in the winter.
The solar you and others here helped us pick out has 580 watt mono panels.
All that is still packed away till we can decide where to put it up.
We had ours packed away for a number of years, I was wanting to start the array frame last year but congestive heart failure put a stop to any of the things I wanted to take care of, even mowing and weed eating got put on the back burner. Mono crystalline panels are known for being the most efficient, how many panels do you have? I don't know if I mentioned this before but when we bought our panels from Grape Solar, I asked them if I needed to have hinged mounts to change the angle of the panels to match where the sun was in the sky and they told me just to make the angle according to what parallel you are living on, that made it easy for us because we are close enough to the 45th parallel that I used 45 degrees, also our solar array is set at the global true south. I went on line and put in the GPS for where we live and it gave corrections for true north, I rough figured from the position of the North Star. If you can get your state Atlas & Gazetteer that has the Detailed Topographic Maps, they will also have what parallel you live along the edges of the pages. Wal-Marts usually have these kind of maps, at least that's where I got ours.
 
This just reminded me to put a clothes line in the greenhouse. it gets really hot in there in the summer and warm in the winter.
The solar you and others here helped us pick out has 580 watt mono panels.
All that is still packed away till we can decide where to put it up.
The Self Reliant Road Show could help you figure that out and probably get you get it set up!
 
The Self Reliant Road Show could help you figure that out and probably get you get it set up!

Weedy thanks for the show and I'll try it tonight. I do want to set it up to make sure after storing it for past few years it works.
I'm probably going to be at it with power company soon over Smart Meter scheduled or next couple months.
 
I do not know exactly where they are going to be in Florida, but it looked like they are driving across the Panhandle. Season 2 is down the East Coast. They want to go west for future seasons.

I'll see of they get fairly close and may check em out.
 
The Magnum Energy inverter/charger I use is for a 24 volt system but they do make one for 48 volt model that's 4,400 watt that is stackable to 17.6 kw, with two it will give you 8,800 watts 120/240 volts, you have to have an ME-RTR router to tie them together, I bought this router just in case I wanted to add another inverter to double our wattage. These inverters have a built in transfer switch and switch over so fast that there is only a slight blink in any lights that are on, even electronic clocks stay on time. Your deep well pump is the largest starting draw on wattage used and a single 4,400 watt inverter would more than likely take care of that as they have a 8,500 watt 5 second surge power capability. Check out donrowe.com , they have a very large brand list to choose from, I bought Magnum Energy because they are heavy duty transformer based pure sine wave inverters which are very kind to things that have electronic controls and are less likely to overheat sinewave sensitive motors. There are also many good makes of charge controllers, I happened to get a Morningstar MPPT-60 solar controller, they are good for up to 150 volts DC input and can be set up for charging 12, 24, 36 and 48 VDC battery systems, at the 48 volt setting they are good for 4,000 watts of array power, many can be tied together to make even charging of multiple battery banks by using a router to connect the controllers.

Ditto on this! Great quality!

We use an ancient Trace inverter/charger (I think they're made by Zantrex now) but we have a much smaller demand. Only complaint against the Trace inverter is that it makes a quiet "buzzing" noise while operating. The newer models might be more quiet. I put it outside so we don't hear it in the cabin. We have a Zantrex 1,000 watt model set up for our electronics like video games, television, computers because when I'd fire up the generator and the inverter flipped to charge mode the kids lost their video games and/or the television turned off. It is set up directly to the battery bank and was not affected when we started the generator.

We have gone to Solar Epic for our MPPT charge controllers. I really like the Solar Epic charge controllers (we have three).
 
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