Adding solar to an old on grid homestead

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Our dear friend, daughter and husband are extremely limited for what they can do, so I've designed their system to get the best bang for the buck, their system will be a lot like what we put in our motorhome. The only batteries they were able to get a hold of are 255 amp-hour and that is very good, their 400 watt solar kit came with a 40 amp PWM solar controller, but I told them that they would do better to use a MPPT controller and it will do a better job on keeping the batteries topped off on cloudy or foggy days that are common to winter days in our region. I'm planning to make a compartment under the solar array to put the four batteries, solar controller, inverter, disconnect box, fuse box and an junction boxes. I'll try and get pics posted as I can. Doing things around this time of year is often not all that easy, considering winter weather conditions, thing is I'm trying to get them an emergency water system and a little electrical power for their small cottage and fifth wheel, I've told the daughter that what I have designed for them is a bare bones system that is also solid, it's something I'd do for us if I had to keep things to a minimum. Considering the cost of the array frame, batteries, controller, inverter, 12 volt water pump, 1,500 gallon water tank and other necessities, it looks like it's in the $3,000 range. What they were looking at before they asked me what they should do, would not have made them happy, in my opinion, it would have failed them just when they needed it the most. The people I've dealt with, like Don Rowe and Grape Solar, have provided some of the best pricing, locally, that I have come across and they are close enough to save hundreds of dollars of shipping when we can pick the products up ourselves.
Their system sounds what I got to start with, I have been surprised at how well the little PWM performed even if all the solar panels had to be wired in parallel. I ended up buying enough extra panels and the 40A MPPT; enough materials to make 2 -400 watt systems. I already had several inverters (both modified and pure sine) sitting on the shelf so I didn't have to buy them. The total cost of my system(s) including 6 batteries was $1900, renogy offered free shipping. The battery cables and fittings set me back just over $100, that's included in the number I showed.

Just out of curiosity what type of water pump did you get? I have my bulk drinking water storage in the basement and I ran a copper house water line and valve over next to the sump pump, the barrels are arranged there with a manifold and 1/4 turn valves at each barrel. I have a 12V RV water pump (Sureflo 65 psi) and I can connect it to the manifold and to the valve on the house cold water. By turning off the city water where it comes into the house (also in the basement) and turning on the RV water pump I can use my water storage to feed the water heater and all the in house water. We have used that a couple of times and the only complaint was when the oldest son took a long shower, he said the water pressure was a little low. The longest we have used it is about 5 days, I ended up having to keep a charger on the battery to keep everything working...

Now I use it about once every 6 months, I run all the water out of the barrels add a little bleach then refill them, but I don't waste any of the water. In a SHTF event I could filter the water from my rain barrels and use it to feed the whole house system. Right now I have a combined water storage capacity of about 650 gallons. I wish I had double that, but I'm glad that I have what I have.... I do keep a spare pump and a couple of overhaul kits just in case......
 
I don't think they got the 12 volt water pump yet, but the one I looked at was from a local electrical and plumbing supply, it was $93 and had a built in pressure switch, I don't remember all the specs but it had a good head lift and it is probably a vane type rather than a diaphragm type which is common to RV water pumps. I think the vane type has a higher flow rate than the diaphragm type, I need to look at the camper supply store and see what they have, either way they'll get pressured water.
 
We have had 4 days of rain and overcast, my solar has been putting out less than 20% of expectations and today the batteries got low enough to trip the low voltage alarm on the inverter.... I bypassed the inverter the batteries were still not fully charged at the end of the day. Based on that experience, if I had to rely on solar I would need to go with at least 5 times as much wattage as I expected to need. Yep that's the lesson I learned, it works fine until it does not...
 
Follow up, I decided to upgrade my outdoor system just a bit. I am going to increase my battery storage by 30% and I am going to re-engineer my solar panel stand to allow me to install 2, 500 watt rows powering 2 40 AMP MPPTs. The inverter I have outdoors worked fine for the Christmas lights but it would not do in a true SHTF event.

For Christmas I bought myself a 1000 watt charger inverter and I plan to set it up with 4 100 AH LiFePo4 batteries, but I need to get my cash flow stabilized before I make that kind of investment, plus I want to wait until after tax season, because it could go either way this year....

My goal is to have everything ready to install by early Spring.
 
I run my house, fur shed and shop all on solar, with a 12 kw diesel backup and auto start. Our well is a quarter mile from the house so its on its own 12 kw propane generator connected to a 250 gallon tank. Our well pump is down 650 feet deep and has a 5 hp motor and connected to a half mile of water lines, all buried 5' deep.
I'm planning on adding another 5 solar panels and a wind generator this summer to my system. My battery bank is 8 six volt lead acid batteries wired to make 24 volts. I'd like to add additional batteries but was told that I'd have to replace all 8 batteries. My generator is programed to start when the battery voltage drops to 23 volts. During much of the winter we get very little sun so the generator starts a couple times a day. Over a 12 month average the generator runs 5 hours per day. I'd like to get that average down to no more than 2. We get a lot of wind during the winter so I think a 1500 watt wind generator should help.
 
There is a way of adding more batteries without replacing all of your batteries, you can add eight more batteries by taking 4 older batteries and adding them to 2 new plus 2 old for each series bank, that would double your battery storage. This is basically what I did with my 24 volt per bank system because I was only able to get 10 batteries at a time from two sources and the manufacture dates from those two sets of 10 were different and I wanted to have them all the same dates if possible so that any differences between batteries would be kept to a minimum, anyway I did 2 new 2 old per series and its worked out great. What I would highly recommend is to do an electrolyte test on each of the older batteries just in case there happens to be any weak cells. I have used the new/old mix before with excellent results on our motorhome solar system which was 4 batteries series/parallel, two of the batteries were already in the motorhome before we installed 400 watts of solar, they looked good but were older, this system with the two newer batteries ran us for 6 weeks out on the north Nevada desert, with just a daily solar recharge, except for one cloudy day when I used the engine alternator for charging. These batteries ran a Xantrex 2,000 watt pure sine inverter which we made two pots of coffee a day and ran an older tube TV and a DVD for up to 4 hours a night, some lighting and the use of a small vacuum cleaner once and a while as well as a 200 watt slow cooker for up to 8 hours. We were pleasantly amazed at how well the solar system performed for just having four 100 watt panels and four GC-2 batteries that gave us 420 amp-hours per charge. We bought our solar panels and MPPT controller from AM Solar in Eugene, Oregon, I asked a lot of questions and they gave me what amounts to an education on solar and how it should be built, as it turned out, it was a primer for the standby solar system we have for our home. I believe one of the most important thing I learned was the need for using high cell count panels that put out much higher voltage than you would think necessary for charging a battery bank, time and again it has shown us how much of a difference it's made when we have cloudy, rainy days, we've even had usable charging on snowy days as well as charge volts and amps down to where the sun was getting to set below the mountains to the west. This is why I tell others that are thinking of going solar to get high voltage panels and use MPPT solar controllers. Originally I designed our solar system to just take care of a minimal amount of things in our home, but because I listened to people who knew what they were talking about, the system has operated beyond what I had expected. I certainly pays to educate yourself before jumping into a solar project, the end result can be amazing. There are others on this site that have much more knowledge than I do, but I'm sure they've put a lot of time educating themselves. We're actually running a low tech system 1560 watts of solar array, 20 lead/acid 205 AH golf cart batteries, a 60 amp MPPT MorningStar solar controller and a 4,000 watt 120/240 VAC Magnum Energy pure sine wave inverter/charger.
 
Yeah, I know my post is long and drawn out and not spaced like it should be, please be patient with me, I really am only self taught, as to a computer and now that I got rid of Microsoft types and I'm using a MacBook, I'm still pretty ignorant, just have less issues and don't swear at this computer, like I used to do with the Microsoft kinds.
 
With the help of our friends' husband we got their solar array frame built on Sunday, this coming Sunday I'll try and get the solar panels mounted and mount the inverter and solar controller above the battery compartment, (which is a large plastic tote), all of this is in the water pump/storage tank shed. I'm trying to get her system together as soon as possible, she is concerned about all the things going on and not being prepared, I told her that by just having the 1,500 gallons of water stored, they will be good, better when they get battery powered, pumped, water into their home of course.
 
I found the best product at the best price for 12V water pumps here.

https://www.kleen-ritecorp.com/p-8907-flojet-04300143a-electric-pump-5-gpm-45-psi-12v.aspx
Been using them for years with a new spare still in the box.
I know these pumps, had a Flojet in our travel trailer. I may just tell my friends to get one to have as an extra, the pump they bought is an offset vane type and came with a spare vane, once everything is all connected it will be interesting to see what kind of water pressure they get in the fifth wheel and the small cabin.
 
With the help of my friends husband we got the panels mounted, he's a sharp guy that sees what I have in mind to do and he automatically follows through. Next time I go over to their place I'll probably get all the basic wiring done, connecting up the panel wires, the solar controller, the battery jumpers and the inverter. I want to set up a 12 volt outlet for the water pump using a 20 amp outlet and plug, the kind that has plug prongs that look like l -- from the end, I don't like using the alligator clips that came with the pump, too easy to get a spark in a hydrogen atmosphere so close to the batteries. Anyway it's all getting close to being operational. I think next time someone wants a solar system, I'll just design it and let them build it, it's truly time for me to really retire.
 
I think next time someone wants a solar system, I'll just design it and let them build it, it's truly time for me to really retire.
With all the good work that you have done, I find it sad to think that you would really retire... I really enjoy hearing about the work that you are doing and the way that you are doing it is inspirational to me....
 
With all the good work that you have done, I find it sad to think that you would really retire... I really enjoy hearing about the work that you are doing and the way that you are doing it is inspirational to me....
Thanks, it may be that I'll say this and turn around and take on another project. The one I'm working on now is rather small but I've ended up being worn out and I didn't pour the Strong-Ty anchors for the 4" X 4"posts. As it is, my neighbor on our east side has talked about having a solar system built on their property and I think he expects me to help him. One thing I'll mention here and this is to help others on this site, is that some things related to solar projects are getting hard to get and wire and disconnect boxes can be iffy, I couldn't find the boxes at the electrical supply place I usually get them and ended up getting a screw in fuse box with a lever switch, it's going to work but the fuses are unnecessary as the solar panel kit came with inline MC-4 fused connectors. Also my friends had a hard time finding four GC-2 6volt batteries, Costco hasn't had them for a number of months, they ended up getting their batteries at Batteries + bulbs, 255 amp hour per battery at $200 + a hefty core charge, the Costco batteries, last time they had them were $96 and they were 210 amp-hour. Anyway, from what I can see, the longer a person delays, the worse things are going to get, even freeze dried and dehydrated canned foods have doubled in price and more over a few years ago.
 
I have been using a 1250 watt inverter with built in transfer switch to power my growing stations lights (they are all on now, drawing about 1000Ws) I used a timer on the grid so the grid powered the lights in the hours when we didn't have full sun. Yesterday the inverter went down.... it over heated the DC line in at the case and then just went completely down. I was not too upset as that inverter was almost 10 years old, but it reminded me of how quickly thing could go south. I have a regular 2000 watt pure sine inverter (no transfer switch) sitting on the shelf and plan to install it with 00 cables. I ordered a stand alone transfer switch and will use it inside the house so I can still split the powering of the growing station... It will be next Monday before I can do the labor on the job.
 
Our 4,000 watt Magnum Energy inverter/chager has a lot of protective devices built in to protect the inverter, Overload, Over-temperature and Internal Fault as well as low and high battery voltage cutout, The only problems I've experienced have been over temp cut out by the FET's, probably due to back draw caused by not shutting off the water heater and the breaker that connects the sub breaker panel to the main grid breaker panel. I'll have to rethink some of the wiring in the backroom sub breaker box, I might be able to rewire the circuit to feed the bedroom,bathroom and the kitchen refrigerator using the inverter fed breaker panel that's outside on the north wall of our home. Dang, why didn't I think of this before, would have kept my DW from yelling at me because she always has to reset the clock radio time every time the grid goes down, I'll get it, I really will.
 
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Our 4,000 watt Magnum Energy inverter/chager has a lot of protective devices built in to protect the inverter, Overload, Over-temperature and Internal Fault as well as low and high battery voltage cutout, The only problems I've experienced have been over temp cut out by the FET's, probably due to back draw caused by not shutting off the water heater and the breaker that connects the sub breaker panel to the main grid breaker panel. I'll have to rethink some of the wiring in the backroom sub breaker box, I might be able to rewire the circuit to feed the bedroom,bathroom and the kitchen refrigerator using the inverter fed breaker panel that's outside on the north wall of our home. Dang, why didn't I think of this before, would have kept my DW from yelling at me because she always has to reset the clock radio time every time the grid goes down, I'll get it, I really will.
I put my wife's clock radio and CPAP machine on a 1500VA UPS so I didn't have to keep resetting the clock... The trouble with doing this stuff is you only see the whole picture after something lets you know you have a problem...

My old inverter had the old DC connectors with the brass ring and a screw for a clamp, so you push the wires into the ring and use the screw to clamp the wires into place, over time the expansion and contraction led to increased resistance and over heating. The newer ones use a threaded lug which is more secure.
 
My new automatic transfer switch arrived today, I will wire it up and try to get it installed this weekend. I also received some new inverter cables so I can install that too. The weekend is so over-booked at this time I will be lucky to get everything working again.

I was hoping to increase my solar this weekend to a full 1000 watts so I could cover about half of the indoor garden needs (800 watts for 12 hrs per day) off solar. I currently only have about 600 watts of solar on line and it is not enough to cover 9,600 watt-hours.

Using the transfer switch and a couple of analog timers really simplifies the planning... I am using kill-a-watt type meters to monitor the power utilization by the system.
 
The new-er inverter is installed and the new automatic transfer switch is setup, the system is delivering 895 watts to the growing station, but only for about 4 hours per day. I wish the transfer switch had longer leads, but it fit the mounting space I had and can just reach all of the other connections. It has been fun to verify it's operation by shutting down the different power sources. Anyway the system is all up and running again. Happy me..
 
I love it when things work, especially when they go beyond expectations. I finally got into the sub panel in the pantry room and rewired some outlets and lighting connections so that they would automatically run when the grid goes down, wife doesn't like to reset the clock radio in the bedroom and I didn't like it that the bathroom outlets which are on a circuit that supplies the large refrigerator in the kitchen, wasn't hooked up to the inverter transfer relay. I'm glad we got the split phase 120/240 VAC inverter, not that we need 240 volts but it does help to balance the load evenly on the inverter as well as having 240 volts available if I ever need it.
 
The new-er inverter is installed and the new automatic transfer switch is setup, the system is delivering 895 watts to the growing station, but only for about 4 hours per day. I wish the transfer switch had longer leads, but it fit the mounting space I had and can just reach all of the other connections. It has been fun to verify it's operation by shutting down the different power sources. Anyway the system is all up and running again. Happy me..

Hey Urban, how much current would be your max draw? It might be possible to build some jumpers to add length to the leads depending on the draw
 
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Hey Urban, how much current would be your max draw? It might be possible to build some jumpers to add length to the leads depending on the draw
My maximum current draw for the device is 15A at 120V or 1800 watts, I intend to keep it under 1000 watts.

I ended up installing my transfer switch inside the house next to the panel and 115V feed from the outdoor inverter, I am monitoring power use from both sources to balance things out.

Today, I finished building my large battery bank, over the winter I had been gathering buss bars and matching cables plus making the box. I used my tax return to buy a full set of batteries on-line. Now that it is all installed I am very happy it all fit. I had all the batteries stored in a tent on the driveway, I think carrying them all down to the basement walkout made my arms longer or my legs shorter... ;) Did I ever tell you that all the delivery guys hate me.......
 
I don't know a whole lot. But sharing what I do know. For my rv I have to watch power very carefully. Have about 400w of solar and thats kind of it for now until my genie is repaired. I cannot exceed 30 amps or ill blow a fuse. So no vacuuming unless I'm hooked to my giant genie.. My fridge runs on LP tanks that I refill (not exchange). My water heater is boiling hot and also runs on LP. It's only 5 or 6 gal but I've NEVER not had enough hot water for even the most lavish hot shower. Idk what the power consumption is for an on demand heater but they seem popular. Using the extend a stay kit for my rvs LP tank might be something that can be hooked up to a home where you can't get LP delivered. Anything I can get in 12v I do. A couple small inverters for charging batteries, phone & laptop. The fridge does take electric when I'm plugged in. I don't have enough to run a heater or ac. I use a mr. Buddy heater. Even the pilot is enough to maintain 50 degrees when it's in the 40s (Nothing compared to alaska! Temps sry) I don't care for the kerosene heaters.. too complicated, too many things that can go wrong with them for me.. I know they make 12v tvs and things like that. I just run a laptop and shut it down to recharge when it's sunny. Laundry is a trip to town for now. LP stove top, but I avoid using it as it seems to chew through LP like crazy. Normally, running my genie for cooking a meal and charging up banks and other things for an hour or two a day if I want. Sometimes in the bitter cold it's needed to keep tanks warm. I also have high capacity rechargeable batteries for things like camping fans, fridge fan, lamps... 12v charger for power tool batteries. So I try and charge when I've got a nice sunny day or can run the genie. Also I have those old school rubber water bladders for staying warm under the covers. Keeps me cozy even if it's 35 inside. Also I've insulated all windows with reflectix and batting on both sides. If I had more storage space I would have a set for winter and summer... but hoping it keeps the heat in (and drafts) out in the winter. And keeps the heat out in the warmer weather. That being said earth is a great insulator. I will be building a skirt with small burms around the rv where I can to try and regulate temp a little. Our home will have burms around 2 or 3 sides to regulate Temps a bit more eventually. We will be using a lot of the 12v rv stuffs in our home. I'm very happy with my water heater and fridge. Also, lastly... dogs!! Mine is trained to climb in my double wide sleeping bag. I'm sure you know every trick in the book for keeping warm up there! But if anything helps reduce power and increase warm yay!
 
Also I've been meaning to look into golf cart batteries. Idk how true it is but a friend mentioned they're better than deep cycle even. A friend built my battery bank a couple years ago and tbh not sure what he did. I know I will need to investigate soon to top off electrolytes. All I know is we have a lot of bank for my needs.

I don't know a whole lot. But sharing what I do know. For my rv I have to watch power very carefully. Have about 400w of solar and thats kind of it for now until my genie is repaired. I cannot exceed 30 amps or ill blow a fuse. So no vacuuming unless I'm hooked to my giant genie.. My fridge runs on LP tanks that I refill (not exchange). My water heater is boiling hot and also runs on LP. It's only 5 or 6 gal but I've NEVER not had enough hot water for even the most lavish hot shower. Idk what the power consumption is for an on demand heater but they seem popular. Using the extend a stay kit for my rvs LP tank might be something that can be hooked up to a home where you can't get LP delivered. Anything I can get in 12v I do. A couple small inverters for charging batteries, phone & laptop. The fridge does take electric when I'm plugged in. I don't have enough to run a heater or ac. I use a mr. Buddy heater. Even the pilot is enough to maintain 50 degrees when it's in the 40s (Nothing compared to alaska! Temps sry) I don't care for the kerosene heaters.. too complicated, too many things that can go wrong with them for me.. I know they make 12v tvs and things like that. I just run a laptop and shut it down to recharge when it's sunny. Laundry is a trip to town for now. LP stove top, but I avoid using it as it seems to chew through LP like crazy. Normally, running my genie for cooking a meal and charging up banks and other things for an hour or two a day if I want. Sometimes in the bitter cold it's needed to keep tanks warm. I also have high capacity rechargeable batteries for things like camping fans, fridge fan, lamps... 12v charger for power tool batteries. So I try and charge when I've got a nice sunny day or can run the genie. Also I have those old school rubber water bladders for staying warm under the covers. Keeps me cozy even if it's 35 inside. Also I've insulated all windows with reflectix and batting on both sides. If I had more storage space I would have a set for winter and summer... but hoping it keeps the heat in (and drafts) out in the winter. And keeps the heat out in the warmer weather. That being said earth is a great insulator. I will be building a skirt with small burms around the rv where I can to try and regulate temp a little. Our home will have burms around 2 or 3 sides to regulate Temps a bit more eventually. We will be using a lot of the 12v rv stuffs in our home. I'm very happy with my water heater and fridge. Also, lastly... dogs!! Mine is trained to climb in my double wide sleeping bag. I'm sure you know every trick in the book for keeping warm up there! But if anything helps reduce power and increase warm yay!
 
My battery bank is currently 12V 900Ah capacity 10,800 Watt-hrs. I have been monitoring it with 400 watts of solar feeding it and the growing station drawing 830 watts it has been fun. I am using timers and an automatic transfer switch to control everything, I run the grow station off the inverter for 1/2 hour and then give it an hour to recharge (the growing station uses grid power during that hour). Unless it is overcast my batteries stay above 11.6V, I make sure that the growing station switches over to grid power at least 2 hours before sunset to allow the batteries to be fully charged at the end of the day. I figure this is the best way I can have emergency solar power backup available and get maximum utilization while preserving my battery life.... It has been a long slow learning process for me but I feel like I am making progress.
 
Our motorhome only has four 100 watt panels on its roof but it does a very good job of keeping the four 210 amp hour batteries charged to full due to the MPPT solar controller, we spent six weeks out on the desert in Northern Nevada in 2008 and only ran the engine one day to top the batteries off on what was a very cloudy day, those batteries were connected series/parallel for 12 VDC and 420 amp hours, they are true deep cycle with heavy lead plates in them, each battery weighs close to 80 pounds. I have a friend that I helped build a 400 watt solar backup system for in the past few months and because of shortages of supplies, they had problems finding GC-2 batteries, they finally found four 235 AH GC-2's at Batteries Plus for $200 a piece plus core charge, those batteries weigh close to 100 pounds each, in other words, you'll need a hand truck or a heavy duty cart to move them around. We got our batteries from Costco, 10 at a time, so that I could get batteries with the same manufacturing dates on them, it didn't matter that the next 10 were dated a month later because I connected them series/ parallel, five banks of four batteries each, two batteries of one month and two of the next month in each bank, it makes for a balanced system that way. Costco is having problems getting GC-2 batteries, probably container ship issues, they still had good prices, when I did see them, around $96.00 plus core a piece, they are generally made by Interstate and are good quality. I'll add a warning here, when connecting these high amperage batteries, always be in a vented area and always use insulated wrenches, wrap the wrench down to the wrench opening with electrical tape, these batteries have enough amperage to weld thick steel, imagine what they could do with a wrench in your hand and as for venting, when batteries are charged or discharged they produce oxygen and hydrogen rich gases, if you have never seen a battery explode, it's very dangerous, just a spark from connecting a wire, like what happens when you connect or disconnect an inverter, could cause you bodily harm.
 
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Yesterday, I took down this solar array: https://www.homesteadingforum.org/attachments/p_20211015_104531_p-jpg.73788/

Today, I completed the new frame that will support an array twice the size.

I set it to 40 Degrees.
P_20220325_161619_p.jpg
The new array is going to be just a little taller than the old array.P_20220326_100016_p.jpg
 
Yesterday, I took down this solar array: https://www.homesteadingforum.org/attachments/p_20211015_104531_p-jpg.73788/

Today, I completed the new frame that will support an array twice the size.

I set it to 40 Degrees.
View attachment 83204
The new array is going to be just a little taller than the old array.View attachment 83205
Our system was such a long term project that I was able to check the angle of shadow behind our home on the longest day of winter and set up the array so that at the lowest point of the winter sun only allows the shadow to come up below the panels by more than a foot.
 
Today I had a couple of hours after work to put the panels back on the array frame. I made my own brackets and they worked okay. The new solar panels ended up being slightly different than the old one, they were wider and shorter than the original 4 I had. I was able to make them fit. I only have 1 mppt charge controller hooked up at this time because I need longer cables for the second controller. I hooked up the new panels (group of 4, 400 watts) and got an over voltage error, over 100 volts. I had the fittings to quickly do a parallel series hybrid configuration, got the voltage down to 49 volts so the system is working, half way. I will spend my free time running a conduit from the charge controllers to the array, by the time the cables arrive I will be ready to install them cleanly.

The design is built on 2 groups of 4, the 4 on the west side will get the early morning sun and the 4 on the east side will get the last good sun of the day.
P_20220329_191547_p.jpg
 
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