My solar adventures

I love bell shaped curves, a 107 kWh day:
108kWh day.png
 
Wowie that huge my average is 33kwh on a 6.4kw system.
That's really good. I have 44 370 watt panels. 22 facing due E and 22 facing due W. They're roof mounted so are at an angle of 18.5 degrees. Not optimally aimed for my latitude. ~47 degrees North here. So they should face S at about 47 degrees. I took this into account when designing the system. It uses micro inverters, which also act as optimizers for shading. On my installation that's only a factor when there is snow. But the micro inverters last about 25 yrs vs 12 for a string inverter and I didn't have to work with high voltage DC power.

So if you just take the raw rating for the 44 panels you get about 16.3 kW. The actual best case is 15.2 kW. And even that they aren't faced in the correct direction I have seen 13.8 kW peak output and max for a day was 120 kWh. I cannot afford batteries for a system like that so I use the grid for storage. We have net metering here so I bank my kW at the current retail rate with subtractive metering over the month. Currently time of day doesn't matter.

There's finally no more snow burying the array so time to save up for next winter. Last year I made about 1.3 mWh more than I used.
 
I'll post more later. @Ozarks Mountain Brew

As an electrical engineer with more than a lot of experience with SLA batteries, some unsolicited advice:

Please, put some kind of protection on at least one of them big battery cables. Like a 120 A circuit breaker. I'll even send you one, free.

One only needs to experience a dead short with such a battery to remember the moment forever.
I’ll second that statement. I was present at a very unpleasant experience when an AutoZone employee shuffled across a vinyl tile floor and touched a defective battery from which hydrogen was leaking. A piece of the battery sounded like a hummingbird passing when it just missed hitting me between the eyes as I watched the poor guy get drenched in sulfuric acid. Fortunately for him I was first aid trained and reacted without thinking to get him to a sink to flush his eyes. I didn’t ask his permission to nearly drown him with water. He can see today because of my reaction and will damn near give me anything in the store when go in it. He won’t let me pay for anything. If you’ve never heard a bomb go off just ask any vet about IEDs. My ears rang for days.
 
Very sexy man!
I like the idea of these micro inverters and the safety handling DC at lower voltages.
My understanding is its more dangerous than AC as DC Don't let go?:eek:

I've had me a small DC jolt once as a kid my bro dared me to grab the main line on an electric fence yeah I piss bolted like crazy after getting jolted what felt like a minute lol.
What you got from the e-fence charger was a mostly capacitive discharge that is relatively low energy, yet very high voltage, similar to a spark plug discharge. We had one that would make a 4000 pound bull run backwards. I don’t think I’ve ever seen anything quite so large in a very bad mood. I watched it give a haircut to a girl I went to high school with when I took her down to our dog yard to see the new pups we had. Her dad’s dog and one of ours were the proud parents, she was the unfortunate victim of the same fence charger that made the economy size bull run backward. She didn’t think it was nearly as funny as I did. The capacitor discharges a lot faster than a battery does, so won’t really hurt anything very big, but it’ll sure make you hurt yourself getting away from it. But you are correct, that DC will convulse the muscle tissue and make it impossible to extend and release. Even pulsed DC is much more horrifying because the current doesn’t pass through zero with the voltage. Spent a lot of years avoiding the inevitable and haven’t had a serious hit yet.
 
What you got from the e-fence charger was a mostly capacitive discharge that is relatively low energy, yet very high voltage, similar to a spark plug discharge. We had one that would make a 4000 pound bull run backwards. I don’t think I’ve ever seen anything quite so large in a very bad mood. I watched it give a haircut to a girl I went to high school with when I took her down to our dog yard to see the new pups we had. Her dad’s dog and one of ours were the proud parents, she was the unfortunate victim of the same fence charger that made the economy size bull run backward. She didn’t think it was nearly as funny as I did. The capacitor discharges a lot faster than a battery does, so won’t really hurt anything very big, but it’ll sure make you hurt yourself getting away from it. But you are correct, that DC will convulse the muscle tissue and make it impossible to extend and release. Even pulsed DC is much more horrifying because the current doesn’t pass through zero with the voltage. Spent a lot of years avoiding the inevitable and haven’t had a serious hit yet.
Oh don't worry we dared eachother to do alot of things with that electric fence:p.

Provided alot of merth:)
 
This is done, all 120v is routed through the inverter through a sub panel, it goes into bypass mode automatically if no sun and the batteries get below 44v, I have a 6 gage cable running back to the main panel so no switching back from this point, I realize I need more batteries and panels but it's a start
 
This is done, all 120v is routed through the inverter through a sub panel, it goes into bypass mode automatically if no sun and the batteries get below 44v, I have a 6 gage cable running back to the main panel so no switching back from this point, I realize I need more batteries and panels but it's a start
Gotta start somewhere. #6 is good for 60A, and bigger wire can be had if need be.

I'm jealous!
 
Gotta start somewhere. #6 is good for 60A, and bigger wire can be had if need be.

I'm jealous!
You can set the amp draw to charge the batteries all the way to120 amps I have the panels set to 60 amps and grid to 30, biggest breaker I could find, I might split a double pull and set it to 60
 
this is roughly how mines set up, not my pic but close and I only have 1 unit so far, it works great but the issue is I'm not saving any money on the electricity bill, first I cant go the whole night on battery, second the grid charges the batteries when the panels are in the shade and it has a pretty big footprint as far a grid draw so between the two I'm just breaking even lol

20220524-215458-orig_orig.jpg
 
this is roughly how mines set up, not my pic but close and I only have 1 unit so far, it works great but the issue is I'm not saving any money on the electricity bill, first I cant go the whole night on battery, second the grid charges the batteries when the panels are in the shade and it has a pretty big footprint as far a grid draw so between the two I'm just breaking even lol

View attachment 25643
Breaking even is better than paying in my books Ozarks good onya.
 
Breaking even is better than paying in my books Ozarks good onya.
Yup. Even if you don’t make them pay you, you’ll pay them less. More batteries will help overnight, but only more panels will help during the day. You’ve got the hardest part done (grid tie) and can add at your convenience. The ROI is slow, but it’s real.
 
Electricity is due to go up 25% in Aus so I'll be wishing I was paying less soon:oops:..

Missus and I installed 6.4KW solar 5 or so years ago but honestly it probably halved our bill not reduced it to nothing.

Batteries are the way to go.
I wish id gone one step further...
 
Electricity is due to go up 25% in Aus so I'll be wishing I was paying less soon:oops:..

Missus and I installed 6.4KW solar 5 or so years ago but honestly it probably halved our bill not reduced it to nothing.

Batteries are the way to go.
I wish id gone one step further...
Yep, though daytime solar is great, power companies don’t want ya putting in batteries to store excess for nighttime use. Takes a pretty big battery bank to run even a small house, if you want to run the AC on it too. It can still knock off the peak use spikes if you have a grid tie system. My BIL down in Port Pirie has a 12KW system, and what he ‘sells’ during the daylight hours offsets his use at night. He’s got a pretty big shed that runs N/S so he put panels on both sides of the roof. Think he said he hits peak output at midday when both sides are at nearly full output. While battery storage is attractive, excess generation will typically have the best ROI and net reduction in utility cost.

Unfortunately, until recently, Southern Company/Alabama Power did not offer net metering for residential services, i.e. they would not pay for cogeneration at residential level. Not only that, they put such stringent restrictions on grid tie systems, they were unaffordable. Not unlike our arcane laws regarding alcohol sales/production, they figured out what they were missing out on. There’s still a pretty big disparity in purchased power and sold power prices, but times are changing and they’re getting pressure from the Government to better align prices so that there is actually some ROI for residential solar system. TVA (Tennessee Valley Authority) is a US Government entity, and pays MORE for sold excess power than they charge for purchased power. I.E. you can actually make a profit if you can sell to TVA. The way it should be. Just think, a home that is unoccupied because it’s owners are on vacation would be a pretty good boost to the grid, which now has to feed all the electric cars that don’t pay fuel taxes.
 
I have 300 amp hours currently at 56 volts and running 2 fridges 1 chest freezer a ceiling fan, box fan and air handler furnace motor. router and pc running all night it will barely make it when I get up, anything else like the patio lights is pushing it ,using the coffee maker or toaster will switch to grid power. my electric company does not do grid tie, this is all off grid
 
I have 300 amp hours currently at 56 volts and running 2 fridges 1 chest freezer a ceiling fan, box fan and air handler furnace motor. router and pc running all night it will barely make it when I get up, anything else like the patio lights is pushing it ,using the coffee maker or toaster will switch to grid power. my electric company does not do grid tie, this is all off grid
Amazing that they STILL won’t allow grid tie, isn’t it? There’s enough rooftop real estate to generate many thousands of megawatts, yet the selfish mentality of utilities is hell bent against customers becoming providers in times of excess. Stupid, I tell ya, stupid.


BTW, I’ll assume you’re already switched to LED lighting? Knocks a chunk outta the bill/demand by simply getting more light for the energy as well as a lot less useless heat from the light.
 
Yeah until I get bigger and more panels it wouldn't help anyway so it's fine staying off grid, I do have it set up to use the grid, just can't sell it back, I'm having a hard time keeping these batteries charged as it is so that's my next purchase
 

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