As regular readers know, we installed a solar power system up here at the house in Pennsylvania. The learning curve has been sharp.
We have 11,000 watts (22 individual panels at 530 watts each) of solar panels at 48 volt output each. They go into two (2) mppt charger/controllers which then go into a 30 kilowatt hour EG4 battery bank @48 volts.
From the battery bank, two 4-ought copper wires go to each of two 6800 watt inverters. The Inverters synch with each other, so the sine wave is pure 60Hz, just like normal grid power.
The 6800 watt inverters can EACH handle a needed "surge" of 8500 watts for 30 min or up to 12,000 watts (each) for one minute.
No aspect of this house, at any point, can ever come near that kind of power surge demand.
As I type this story at 8:46 PM eastern time, we have the gas furnace running, the front porch light and rear deck light on, my desk lamp, a light in the dining room on, the under-cabinet LED's in the kitchen on, the big screen TV and home theater system in the living room, all operating, and the total energy demand of the house is only 1.7 kwh.
In every regard at this moment, life goes on here as if nothing at all is different from normal.
At that rate of power consumption, we have 15 hours of full power available from the battery bank. When we go to sleep and turn off the TV, lights, etc., the draw will go lower.
Twelve hours from now, the sun will be up and the solar array will begin generating power.
Unpleasant Surprises
Once the system became operational the first big unpleasant learning curve item was the voltage coming from the solar array.
The 22 panels are divided into two electrically-separate arrays of 11 panels each. Each single array is wired in SERIES, so each of the eleven panels at 48 volts each is added to the voltage total going into the mppt charger controllers. 48 volts times 11 panels would mean a maximum voltage output of 528 volts. Except we weren't getting that much; at least not consistently. We were actually averaging about 193-208 volts per eleven panels.
Well, that just wasn't enough "punch" to charge the battery bank in any speedy way. It could put maybe 2-3kwh into the battery bank at peak, maybe charging it by ten to fifteen percent over an entire day. WAY INSUFFICIENT.
We found out that solar panels have a nasty aspect to the way they handle voltage. The entire array self-limits to the output of the lowest performing panel!
So if ten of the panels are in full, bright, sunshine, but one panel is in the shade, the voltage from the ten in the sunshine would only be equal to that of the panel in the shade.
In order to get around this, we had to go buy 22 "Optimizers;" one for each solar panel. Those optimizers were $50 each (x22). They attach to the rear of each solar panel and accept into them the positive (output) from that single panel.
The Optimizer then connects __its__ positive output to the next optimizer on the next panel and so on. By using these optimizers, we work-around the voltage limiting of the poorest-performing panel.
We finished installing them around 2:30 this afternoon, and the sun, at least up here in northeast Pennsylvania, was already west of the southeast-facing panels. At this time of day in the past, we were luck to get 0.5kwh to 0.8kwh from the panels, but TODAY, it was up around 2.0 kwh. The voltage was also very much improved, over 500 volts.
So tomorrow, which is expected to be a clear day here, we will get our first real look at what the solar array can actually do, now that the learning curve is over and the optimizers are all in.
As such, we decided to run-down the 30kwh battery bank tonight, deliberately, by shutting off the power pass-through from the local electric company. No grid power at all is coming into this house, and it will remain that way until tomorrow morning.
On any regular day, this house routinely uses 50kwh. That's a LOT of energy, but we're spoiled by having grid power. Realizing that the ENTIRE battery bank can only provide 30kwh, (and you can't run it down to zero) our lives will be hugely different if the only power we have to rely upon is solar. It will be bare essentials only: Refrigerator, freezers maybe a light on. But if the solar can recharge itself enough each day, then we'd have more access to the nicer things we are spoiled with.
So tonight is the test to see "what's what" with this new system. How much does it power, for how long, in real life circumstances, in the cold of winter when the temp outside is 30°, and dropping to 20° overnight.
I thought about buying a second 30 kwh battery bank but what good would that be if the solar array can't fully charge even one in a single day? Besides, that battery bank is way expensive (~$8600.) and I don't have that kind of money laying around to just go buy it. I refuse to go into debt for it, so right now, I have what I have and that's it.
Yes, I have a gasoline generator and spare fuel for it. But that fuel is precious and the generator guzzles about one gallon per hour. So when the gasoline runs out --- and if we're in a SHTF situation where there is no gasoline to even be purchased --- We have to know NOW what we can and cannot do with solar power. Hence, tonight's big "test."
I'll let you know how it goes.
UPDATE 7:30 AM SUNDAY MORNING
I got up at 7:22. It was 16° outside. The battery bank is down to 46% because my wife needs an oxygen concentrator on all the time and it ran all night at 300 watts. The math is simple: 300w for twelve hours equals 4.2KW
The sun is almost up, but as of 7:30 AM, the solar panels had not yet begun to send any meaningful power to the mppt charger/controllers.
By 8:20 AM, the batteries were down to 42% but solar panels had begun sending energy into the system. 0.8kw at 192 volts. We __are__ getting sporadic Over-voltage alerts from the Schneider mppt charger controllers, but each time, that clears within seconds.
So now that the sun is visibly over the mountain to my east, we should start getting good solar generation into the system, which should charge the battery rack. We'll see.
You know, I did the math last night as I was laying in bed, about my wife's Oxygen concentrator. 300 watts an hour to run times twenty four hours is 7.2kw. About one-quarter of my battery bank capacity.
This is a problem. How do I tell my wife she can't use the oxygen machine if we're in a SHTF situation??? I just can't do that.
Really hoping the solar array does its thing today.
----------- MORE:
We are getting over-voltage alerts from the Schneider mppt charger/controllers. They are rated at 600 volts. The system is not supposed to be sending more than 528 volts but the mppt charger/controllers are alerting to over-voltage.
In fact, they just went into SHUT DOWN for self-protection.
We checked the software and they are set to alert of the voltage exceeds 585 volts for ten seconds or more.
The reporting from the mppt controllers is showing voltage around 200 volts (still), so this over-voltage does not make any sense.
We were told that in very cold weather, the panels __may__ give off higher voltage than typical. So my son is out there right now removing one panel from each of the two arrays. That will drop the overall voltage by at least 48 volts and we'll see if that solves the over-voltage situation.
UPDATE 9:41 AM EDT --
The equipment I am using is:
SCHNEIDER XW-PRO 6848 INVERTERS (2)
SCHNEIDER MPPT-100-600 CONTROLLERS (2)
EG-4 30.72 kwh Battery Rack:
We went back into the Owners manual for the MPPT Charger Controllers and saw another big surprise: They can handle 600 volts, BUT . . . . they won't charge from 550 to 600 volts! Look:
The voltage needs to be LESS THAN 550 volts in order for them to charge! So this is yet another unwelcome surprise.
As mentioned earlier, my son went out and took one panel off each array - bypassed it in the wiring - to bring down the voltage. We _are__ getting some charging now, but the max output we've seen this morning from the solar panels is only 4kw. Look:
This from a solar array that is __supposed to__ max out at 11kw (10kw now that two panels are removed).
We will monitor the system on and off throughout today to get a better idea of the actual performance, but I've got to tell ya, I think we got snookered as to the real performance of these solar panels. Maybe I'm wrong, but I have this feeling the panels are __not__ what they claim to be.
UPDATE 1:10 PM EST --
So we're eating "Brunch" which was really breakfast: Scrambled eggs, Jones Sausage, toasted white bread, and orange juice, when we hear a shotgun blast outside; really close to our property. It's hunting season and it is not unusual at all to hear distant shotgun or perhaps rifle fire. But this was close. Then, we hear a second shotgun blast.
Since nothing hit the house, we're OK; nothing to do about it because we know it's hunters.
I go out on my rear deck to smoke and as I look across the road, I see three guys in hunter orange clothing on the hill just up from my property. I called out "Hey guys, what'd you get?" They replied "A big Doe."
The Deer is at the end of the red arrow.
Then one of the guys told me, "My 7 year old got him" and sure enough, one of the guys in Hunter Orange was this little kid, with a squeaky voice, all excited that he got a deer."
It was great. A father teaching his son what it takes to actually survive in this world.
They took a few minutes to gut-it right there on the hill, then apparently they called a friend who came down my road with a pick-up truck where they loaded it in the back and off they went.
Ahhhhh country life.
Back to the solar situation . . . . As of 1:04 PM EST, at peak sunshine for today, we only got a maximum of 5kw output from the solar panels. That is a huge disappointment from an array rated at 10kw.
The battery Bank is only up to 52% charge, up from the 40% it was at as the sun began to generate electric in my solar panels. Twelve percent charge, so far, is woefully inadequate to the survival of me and my family.
WOEFULLY inadequate.
So my son and I will wait until the time of day when the solar panels are providing nothing to the charge, and we decided we will intentionally power-up the GENERATOR to see how long it will take to fully charge the battery bank while still supplying the house.
By the end of today, we will know we used X amount of power on a typical day, we got X amount of charge from the panels on a reasonably sunny day - albeit with intermittent cloud cover, and the generator had to run for X hours (on X amount of gasoline) to fully charge it the rest of the way.
Then we know how much time we have to survive - given the gasoline reserve we have, if everything goes to hell and even if gasoline is not available. Right now: We would survive not too long at all.
It's a very sobering realization to have this fact-based assessment of my family's ability to survive. Very sobering indeed. Frightening, actually.
UPDATE 3:15 PM --
At about 2:00, we noticed there was more power coming OUT of the battery bank than going in from the solar array, so I said to my son, let's go hook the generator up to charge the batteries now while we still have sunlight. This way, we get to see how long it will take to charge them with the generator. He agreed.
We go hook up the Westinghouse 12,000/15,000 generator that I have used in the past to power the house when the grid was down. We go to start it. It cranks . . . . slowly, then stops. Try again. Click. Click. No cranking.
We both said "Dead battery." So he gets the NICCO "Genius" 10A Charger out of the house and hooks it up. Almost immediately, it shows FULLY CHARGED.
Uh Oh. If the battery is fully charged, then maybe the starter motor is bad????
We bypass the starter relay to test it without the relay, same thing, click, click.
So we go get jumper cables from my truck, and bring out a new 12 volt car battery. As we go to hook it up, I notice that the fuel line valve is ON. I never shut of off the last time I used the generator. so for months, the gasoline has been dripping into the carburetor and evaporating. UH OH, the carburetor could be full of varnish.
We hook the car battery up and the generator cranks just fine. Doesn't start. I press start again, and it turns over and begins running just fine. A bunch of blue smoke came out at start-up, likely all the evaporated gasoline "gack" in the carburetor.
We tell the inverters to begin using the generator to charge the batteries, and they start trying to pull like 60 amps from it. WAM. Tripped the breaker.
So we had to go into the solar software to tell the inverters to only charge at 50% of the max charge rate. RE-initiated the charging and everything seems fine.
At 2:06 PM we began charging the battery bank which was at about 50%. By 3:12 this afternoon, an hour and six minutes. the battery bank is now at 76%. So 26% charge in about an hour. That's good. Another hour and we'll be up around 95% and ready for another 24 hour period of running just on solar. We won't do that; we'll go back onto the grid.
Today we learned that the charging circuit had to be backed down, and also learned we need a new battery on the generator.
It's a process. Better we learn now, than when the SHTF.
SOME DIRECT ANSWERS 4:30 PM EST --
I keep reading in the comments area that I should have a wood-burning stove. I HAVE ONE! It's been here for years. I have maybe one cord or a cord-and-a-half of firewood outside. I've been wondering if maybe I should get more?
The stove is in the living room. When it's on, the living room cooks up to 80+ degrees, but the REST of the house does not share that warmth. The rest of the house gets downright chilly because the thermostat is in the living room.
I routinely use ceiling fans in the living room to dissipate the heat into the rest of the house, but if electric is not available, the rest of the house will go cold without the fans moving the heat.
I also keep reading about my water heater. I have a TANKLESS water heater. It turns on when a faucet is turned on. It uses propane to heat the water in the water pipe, so there is no storage tank to constantly keep heated.
I have a gas fired stove and oven, also uses propane.
I have four 150 gallon propane tanks, which the local gas company fills to 100 gallons each, so as to allow for safe expansion. That means I have 400 gallons of propane, probably 350 now since last top-off. This propane fires the stove, the oven, the hot water heater, the furnace and the clothes dryer.
I have an outdoor propane barbecue grill with three spare tanks of propane.
I have a refrigerator, a small freezer in the laundry room, and two large freezers in other areas of the property.
So the electric I have or am able to generate, would need to supply the refrigerator and three freezers at minimum, and my wife's oxygen concentrator, which is on 24/7 and uses 300 watts, and also maybe the well pump once in awhile if the house calls for more water. That's NOT a big demand on electric as far as my thinking goes. Maybe my thinking is wrong.
I unplugged the two satellite uplinks last night just to get a reading and was surprised they pull about 90 watts each. If I shut down the radio show computer rack and the outbound internet connections and router, that will drop some more watts.
It's just really surprising to see just how much electric we use AND TAKE FOR GRANTED, that we flatly will not be able to use in a SHTF scenario.
This whole practice run has been a gigantic eye-opener! A real learning experience.
ON AN EMOTIONAL LEVEL . . .
On an emotional level, it's been rather ugly, too. My wife simply will NOT come to terms with the idea that our life may be interrupted in ways neither she nor I have ever encountered before.
When I told her this afternoon that even her using the laptop might not be possible, she about flipped her lid. She creeched at me "This won't work, that won't work, maybe we should all just die."
I looked her square in the eye and replied, "Yes, that might be best." I meant it, too.
I am living with the single most spoiled brat in the world. I give this girl EVERYTHING and she takes it ALL for granted. I am the single most un-appreciated man on earth and frankly, I'm more than tired of it.
I feel like I'm living with a person who has become actual emotional poison. Won't cook. won't clean. Won't get off her ass to do much of anything. Of late, she won't even cook dinner; wants to Order-out all the time.
We're in Bum Fuck Pennsylvania, ordering-out isn't a big option here. I've got freezers FULL of food, she won't cook (again) tonight because . . . . her back hurts, or her knees hurt, or whatever the fuck else she comes up with. A new excuse every day.
Expects it all to be done for her because "she can't." When asked why she can't, she replies "Because I can't."
I'm almost at my wits end. I've really, truly, had enough of this. I don't want this anymore. Something's gotta give. This can't go on.
