Adding solar to an old on grid homestead

[UrbanHunter]

The difference in dimensions between my old panels and the new set had me really questioning myself... Did I order the wrong parts? WTH is going on...? So I go back to my Emergency Backup Set of Panels (new in the box) and yes I have a backup for my backups. Box part # is the same, open it up and the corners are the same as my old panels (this is where the designs changed) and the dimensions are the same as my old panels...

So here is what I have deduced:
1) Sometime over the last 2 years the design changed but part numbers did not (I have been buying them in sets of 2 as I got funds).
2) The newer panels have a different "cell" design too, it's visible
3) The newer panels have a significantly higher operational voltage (over 25 Volts), which resulted in an over voltage alarm on a 100 Volt charge controller

So here's the rub, I have the newer panels installed, but they don't fit the array fixture I built properly and I have 2 choices to fix the problem:
1) Ignore it, it's working, and it's out of sight. But I know it's not right.... and I should modify the fixture to hold everything properly...
2) Take down the newer panels and install the backup panels (original design) I have, but I will have to replace 3 hold downs I made and it will be a couple hours of labor on my part, but it will be as I had planned it to be. The new hold downs will cost me $3 in materials.

I can't do anything until tomorrow evening and the materials for the final installation (new cables, fuses, and disconnects) will not be here till the 8th....

Note to self, when doing one of these projects try to buy all the parts at 1 time to avoid any part design change surprises.

 

[UrbanHunter]

I set up the additional charge controller, so now I can utilize the full array. I checked and I have enough of the old design panels to replace the misfits on my array. The array support is what I would call a minimalist design, but I installed I-bolts at the top and bottom corners of the array frame that will be paired with anchors at the ground level, I am installing the anchors this morning as we have high winds coming tonight and I want everything tied down. I am going to replace the 4 offending panels this morning and re-box them, I have pre-arranged everything an I think I can get it done in 30 minutes this morning.

 

[UrbanHunter]

Here is the update I have exchanged the solar panels and the ones I had fit my frame design, no modifications needed. I had made enough extra brackets that I only lost 1 at a cost of about $1.25. The panels are installed, the anchors are connected and tied down using cargo ties, and the whole works is connected to my DC power center. Total time working 35 minutes.!

It's time to start back on my day job.

 

[UrbanHunter]

Today we had overcast and high (60 MPH) winds, everything stayed put. The panels were not putting out great because of the clouds, about 10 amps going into the battery bank (~120 watts). But everything is working, my extra fittings for my power conduit arrived but I still don't have the proper length cables to minimize connectors. I will be glad when I get this project complete and behind me.

 

[Neb]

Today we had overcast and high (60 MPH) winds, ...

. I will be glad when I get this project complete and behind me.

After you upgrade it to run whole house AC and an arc welder?


Ben

 

[UrbanHunter]

After you upgrade it to run whole house AC and an arc welder?
Ben

I wish, I have learned so much over the last year and what I have come to KNOW is that solar is un-reliable because sometimes, "the sun don't shine and the wind don't blow".

My goal was to have solar emergency backup for up to a 400 watt draw, I've got that covered now.
The second phase was to be able to use the available power on a daily basis to avoid waste and I am now powering my growing station over half the time, it has a 12 hour 800 watt draw when everything is on.

My battery bank is sized for about 7500 usable watt-hours, or 19 hours at my target draw rate. So the goal of having an emergency silent power supply has been achieved. When combined with my generator and a small store of fuel I am good for a few weeks of total grid down operations.

I have slowly gathered a stash of "SHTF backup" Solar equipment that could double my capacity had this been an actual emergency....
But, if I had a few extra bucks I wouldn't mind investing in a few more

I think if I were trying to power a complete 5KW/hr house, I would want about 20KW of solar and 75KW/hrs of storage capacity. That is just way beyond my operational budget. But if I won the lottery it might be something fun to do.

Urban

 

[viking]

After you upgrade it to run whole house AC and an arc welder?


Ben

When you start putting together battery banks like I did and probably others here, all we have to do is connect welding cables to our batteries and they'll doing the job, the higher the voltage the better, 48 VDC is probably much better than our 24 VDC. Usually you need a pretty goodly amount of voltage to get a welding arc going.

 

[UrbanHunter]

Today is the first truly sunny day since I updated the array, I'm out working on the conduit from the array to the charge controllers, it's fun to peek at the little monitor that I made, the inverter is pushing 840 watts to the growing station, the battery bank is holding between 12.2 and 13.1 volts and the system inverter is drawing about 25 amps from the batteries, so about 60 amps is coming directly from the solar. Right now the solar supplies about 1 hour of power, then gets a 30 minute break to recover, then another hour on, that what it seeing for 10 AM till 5:30 PM, this way I am getting something valuable and still can close out the day at 100% charge. I got an update on the cables I ordered, they should be here Monday, so have all the conduit laid out this weekend will be perfect timing.

 

[viking]

Just after the sun set our solar array was still putting out 74 volts and the solar controller was float charging at 1.47 amps, I love seeing those figures, it means our system has exceeded my design factor and it bodes well for the future when the panels loose some of their efficiency. I'm grateful for those solar suppliers that gave me good information.

 

[UrbanHunter]

I was looking at a "failed" inverter that was only about 8 years old, it appears that the bulkhead fitting may have had too much resistance and overheated melting the plastic insulation, I can see a shiny spot where the brass may have made contact with the housing through the plastic insulation, the wires inside the case look fine and none of the fuses blew, I'm thinking I may be able to repair this one by just replacing the bulkhead fittings. I found some online for $25/pair - 500 amp rating at 12 volts, that should work. I'm mad at @Biggkidd because he posted about a cheap inverter he found, I looked and that lead me to a Cobra 2000 watt inverter with a "wireless remote" that shows voltage in, voltage out, and some other data plus you can turn the inverter on/off using the remote, says up to 10 meters away for $208. It will be here tomorrow, dang you biggkid!

It's been raining and overcast here for the last 3 days, the solar is only producing about 50 Watts. I am learning so much about this stuff that I never expected to learn. My new cables will arrive on Saturday, I have been laying the conduit between the panels and the controller, when it's all done it will be a continuous run with the only connectors right at the panels. Right now it is Gerry Rigged with too many connectors and it's a real trip hazard, I look forward to getting that all contained.

 

[Biggkidd]

I was looking at a "failed" inverter that was only about 8 years old, it appears that the bulkhead fitting may have had too much resistance and overheated melting the plastic insulation, I can see a shiny spot where the brass may have made contact with the housing through the plastic insulation, the wires inside the case look fine and none of the fuses blew, I'm thinking I may be able to repair this one by just replacing the bulkhead fittings. I found some online for $25/pair - 500 amp rating at 12 volts, that should work. I'm mad at @Biggkidd because he posted about a cheap inverter he found, I looked and that lead me to a Cobra 2000 watt inverter with a "wireless remote" that shows voltage in, voltage out, and some other data plus you can turn the inverter on/off using the remote, says up to 10 meters away for $208. It will be here tomorrow, dang you biggkid!

It's been raining and overcast here for the last 3 days, the solar is only producing about 50 Watts. I am learning so much about this stuff that I never expected to learn. My new cables will arrive on Saturday, I have been laying the conduit between the panels and the controller, when it's all done it will be a continuous run with the only connectors right at the panels. Right now it is Gerry Rigged with too many connectors and it's a real trip hazard, I look forward to getting that all contained.

LMAO Always my pleasure to help spend someone else's money! Wish I'd seen that one got a link?

Cloudy as it can get here and when I came in a little while ago I noticed the battery bank running voltage was around 56. Adding that third string of panels (1200W) sure made a difference.

 

[UrbanHunter]

LMAO Always my pleasure to help spend someone else's money! Wish I'd seen that one got a link?

Cloudy as it can get here and when I came in a little while ago I noticed the battery bank running voltage was around 56. Adding that third string of panels (1200W) sure made a difference.

My panels are delivering good voltage (between 50 and 70 volts) on the overcast days, but the amperage isn't there. I made a system to monitor the current between the battery buss bar and the distribution buss (inverters and charge controller input connections) so I can watch what is actually going into and out of my batteries. This way I can say okay I'm pulling x amps out of my battery bank when the inverter is drawing Y amps, so my charge controllers must be delivering z amps; Y = x+z.

Sorry it was not a cobra it was an SL-Euthion, when I read the reviews and the guy started talking about the wireless remote I bit and ordered: "SL Euthtion 2000W Pure Sine Wave Power Inverter 12V DC to 120V AC 60HZ with LCD Display, USB Port, Wireless Remote Control（10M）, Solar, Outdoor"

Tried to embed a link but it wouldn't take, so I copied the text of the item, I found it on Amazon.

 

[Biggkidd]

Yeah I was talking about battery bank voltage not panel to charge controller voltage. I've got roughly 600AH @ 48 volts. So for the voltage to be that high at that time it means my batteries are near 100% charged. This is a constantly running system that powers our entire house. Just looked and even with todays rain and pure cloud cover we made 3.3 KWH and still charging @250+ watts with the sun behind clouds and trees. By 4pm +- direct sun is off my panels.

 

[UrbanHunter]

On Friday, I was able to layout the conduit from the array to the charge controllers, 40 feet of conduit with 3' left over, peace of cake.
On Saturday morning, my 2 sets of 40' solar cable arrived! Yea!!! So I created 2 pair, taped them together and the taped the 2 pair together to make the pull. I had almost finished the pull when I realized that my cables were going to be about 3' shorter than the conduit So I had to un-pull the last half of the cable run, re-design on the fly to reduce the total run by just a tad, thank goodness I had some 45 degree fittings and a place were I could make it all fit. I didn't have even 1 foot to spare.

Note to self, when ordering ready made cables in the future, go just a bit long.....

While doing all this I noticed that a cable pulled out of one of my charge controllers, when I was attaching my disconnects I had something similar happen. Both were clamp down connections and the multi-strand cable just can loose as a result of movement. I remembered a video by a German electrician who was saying that using ferrules on multi-strand connections are a must for joint integrity, so now I believe him. I ordered an assortment of them and will be installing them at every clamp down connection.

This morning I finished connecting the new cables to the array and the charge controllers just before the sun came up and then I checked the voltages and everything as I was leaving for the range around 07:30. I didn't have time to collect the old cables, but when I got home from the range I separated all the segments and then paired them up and tied them together, now I have 4 sets of short cables sitting in reserve and the cable runs to my array is no longer a trip hazard.

 

[Bacpacker]

One thing I decided a few years ago when we did several solar installations at work. Just order spools of wire, it cost a little more up front, but you'll have some on hand for another project.
After working on PLC's for a while, Wife Ferrules are a must have
Glad you got the project moving well along

 

[UrbanHunter]

This solar thing is a little like wack-a-mole. I get 1 issue resolved and then another pops up. The larger solar array is working great, the charge controllers are working fine, the batteries are staying charged (12-14 volts), but the 12 volt inverters are failing much faster than I would like. The first inverter failed within 3 months of installation, my bad I was requesting that it run at 90% of capacity and it just cooked itself to death. So for the second inverter I doubled the capacity and it worked well for about 6 months then we had 3 90F+ days and it failed with an internal overload.... I am thinking that I am going to have to install a larger unit and a supplemental cooling fan to help keep everything work in the heat... NOT HAPPY... But, I'm not giving up either.... I will make it work!!!

FYI - Right now I am using about 850 watts for 10 hours per day (two 5 hour on periods with a 2 hour recovery period in the middle) the batteries are staying at 12 volts or above, total draw by inverter is 78 amps, the charge controllers are delivering about 65 amps to the batteries, but the batteries are usually back to 13.2+Volts by the end of the day. Each battery is only "seeing" about a 2 amp draw when the inverter is running, so they are not being over stressed.

 

[Biggkidd]

All these parts like 70 f They do not like hot & humid at all.

 

[UrbanHunter]

I haven't posted here in a while. All Summer, I have been using my inverter to run a 1-hp boost pump to drive my irrigation system a half-hour a day, it has been working well and I am happy. However, with only 800 watts (Max) of solar I did not have sufficient power available to run my indoor grow lights for 12 hours per day, they just draw too much. So I am adding another 800 watts of solar and increasing my FLA battery bank to 1200 amp-hours (Ah).

I also bit the bullet and added a 400-Ah indoor LiFePo4 battery bank connected to a 1000 watt inverter charger. This is being placed on a small roller cart and will be installed between the grid and the O2 generator (draws a constant 450 watts).

My thinking is that in a SHTF event, this arrangement will allow my to keep everything going with minimal use of the generator. My estimates are that I could get by with less than 4 hours of generator per day and still have all the essentials (o2, Fridges, Freezers) working.

 

[Bacpacker]

Good job Urban.
Solar is a major sticking point for me. I have a minimal amount just for maintaining batteries. Just haven't put what funds I have to it yet. May not get there.

 

[UrbanHunter]

Good job Urban.
Solar is a major sticking point for me. I have a minimal amount just for maintaining batteries. Just haven't put what funds I have to it yet. May not get there.

Yes the money part is a sticking point for me too.. I have been buying 2 panels at a time when I can afford it and then keeping them in storage until I can put them to good use. I am strictly making a backup power system, not grid tied and I am learning a lot as I go. I have learned that I wish I had purchased a larger charge controller (60+ amp) at the onset.

I currently have 4 (40 amp) controllers, but I could have done the job with just 2 of the 60 or possibly 1 of the much larger units. Unfortunately, I can only muster about $350 extra a month (the better half tracks my "fun" spending) , which will cover 1 of the charge controllers or 1 of the LifePo4 batteries. So I buy my parts over time and then assemble something when I have everything together.

My last battery arrived today (I ordered it last month) so I am charging them all up before connecting them together. So my shopping list has been 1 per month. This month I ordered 2 solar panels to complete my upgrade, they should arrive before next weekend.

I have parts sitting on shelves that have been waiting for over a year to be put into service. I hope to have things running well by Thanksgiving. I keep feeling that we will be seeing the rolling blackouts here right after the elections are over..... I may be paranoid, but I just can't get the feeling out of my head....

 

[Bacpacker]

Thats been a great way for you to do it. Sort of "Dollar Cost Averaging" if you will. But nothing good come quickly.

Long term I'll be happy with enough to charge some small batteries and run both freezers and the fridge, maybe a couple lights.

 

[UrbanHunter]

Thats been a great way for you to do it. Sort of "Dollar Cost Averaging" if you will. But nothing good come quickly.

Long term I'll be happy with enough to charge some small batteries and run both freezers and the fridge, maybe a couple lights.

Yep. I have found that if I have a long term plan in a spreadsheet I can plan things out around my budget. I can also watch the prices and that way I can be ready if things go down for a day or 2. The best I have been able to do is save $10 here and there. I have run into a couple of issues with the price being right but the inventory being sold out...

My current plan is to have 1600 watts up and going all the time. The long term "emergency" configuration would double that. But at my current rate it will take me another 6 to 8 months before I can gather all the parts and pieces I will need.

 

[Mountain trapper]

At the end of August I replaced my old battery bank. The old batteries were 8 @ 6 volt 430 AH each. My new battery bank is 12 @ 2 volt 1169 AH each. My goal was to cut the generator run down as much as possible. The run time went from 5-7 hours per day down to less than 2 hours average.
My next project is to add 4 additional 415 watt solar panels. I currently have 10 each 295 watt panels mounted on a 20', 8" schedule 80 pipe. The new panels will be mounted on a 6" schedule 40 pipe.
With the high cost of fuel, these improvements will pay for themselves in probably 2 years or less.

 

[UrbanHunter]

This week has been interesting, we have had rain and overcast for 5 consecutive days. The solar panels are still putting out but only about 35% of rated. With the building of the "greenhouse" over the battery box and my plans to run everything inside the greenhouse off the solar there are some clear limitations now. On days like these I can either have 9 hours of "supplemental" lighting, 4.5 hours of heating, or some combination of the two. But not both and it will not cover 12 hours of lighting and heating...... I am planning to double the size of my solar array soon which will help. But, I figure I should be planning around bad weather and overcast days....

This is also letting me think about how much "battery" I need to cover the demand during the hours of darkness.

On a side note, this weekend I took down the 200 Watt "learning" array that I used when I was first thinking about the possibilities with solar (it was shading the greenhouse). The 2 old batteries I used with it still hold a charge, but they are much older (7yrs) than my primary battery bank so they can't be used there. I am thinking that because my irrigation pump only runs about a half hour a day, I could use those old supplies to make a small isolated battery bank and array to power the pump and work lights inside the greenhouse. There are a number of logistical issues that will need to be worked out before this can be executed.

 

[Bacpacker]

When we designed out solar system to power remote several Eco-Gamma systems, we started off figuring out what our total draw was for a 30 day window with no sunlight. Basically a full winter month with bad weather. Then went with enough battery to cover that. I think each station has a 250 to 300 watt panel on it. I don't think we've had a single power failure on any of them yet. But I am betting after 4 years we will start seeing some charging issues within th enext couple years. With nearly 30 of these scattered around, thats a lot of batteries to replace. Reminds me I need to submit a rolling quote to start phasing them in rotation over the next 3 years. All the wifi antennas are close to end of life as well.

 

[Neb]

I have solar panels new in the box along with everything except the batteries and copper to cover an EMP. But The Princess found there is a government deal to subsides green energy.

So I have an appointment for next Monday to get someone to quote me what it will cost. If the government is going to pay for solar, I at least should find out the details.

Ben

 

[UrbanHunter]

I have solar panels new in the box along with everything except the batteries and copper to cover an EMP. But The Princess found there is a government deal to subsides green energy.

So I have an appointment for next Monday to get someone to quote me what it will cost. If the government is going to pay for solar, I at least should find out the details.

Ben

Make sure the system the quote they give you includes a version with some sort of "standby" power for when the grid is down!

 

[UrbanHunter]

I hope that by this weekend to have my extra solar panel array installed and a thermal collection system to provide auxiliary heat to my little greenhouse...
Right now the greenhouse is running purely off solar, but that a gardening section thing.

 

[Neb]

Make sure the system the quote they give you includes a version with some sort of "standby" power for when the grid is down!

Why have solar if it doesn't provide standby?

No joke

Cost per unit energy is best coming from the grid be it electric or gas. They keep the system operational as part of the service. My own system puts the cost of maintenance on me. If the government wants to fund me going independent I am cool with that.


Ben

 

[Bacpacker]

I had some folks come out and talk about a solar system. Nice set up, but no batteries. Total grid tied. Told him to hit the door