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What's the max generation you've seen for a 16.2kWh system at any given time?

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It is sad to see the continued reduction in solar production. Can't wait for after the new year when it will go in the opposite direction.

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Actually, you only have to wait until December 21st! ;)
Yes, it is sad to see the numbers decrease. Our daily production is already down 45% since peak production numbers back in May/June.
 
It is sad to see the continued reduction in solar production. Can't wait for after the new year when it will go in the opposite direction.

View attachment 596503

Wait till Late Dec / Jan. My production in late december / early january on a cloudless, sunny day, is a little less than half of what it is in June on same said day (from 51 ish kWh in June to 22 ish kWh in dec). Given we are in the same area, I would expect your production to be pretty similar, especially based on our previous reports of same day production.

You wernt installed in June to see that production, though... but right now, for reference sake, I am seeing around 35-37 kWh a day, and that will drop down to around 21-22 a day in late december / early jan,
 
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Wait till Late Dec / Jan. My production in late december / early january on a cloudless, sunny day, is a little less than half of what it is in June on same said day (from 51 ish kWh in June to 22 ish kWh in dec). Given we are in the same area, I would expect your production to be pretty similar, especially based on our previous reports of same day production.

Just playing around with PVWatts, it seems like winter production is pretty highly dependent on azimuth. I have panels facing all 4 cardinal directions, and my real system is expected to produce 33% less compared to a hypothetical all-South system of the same size in December, but about the same amount in June.

Screenshot from 2020-10-08 11-35-21.png
 
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Actually, you only have to wait until December 21st! ;)
Yes, it is sad to see the numbers decrease. Our daily production is already down 45% since peak production numbers back in May/June.
That's just about where we are with our system, and the expectation based on PVWatts data is that we be down 60% from the June numbers to the December numbers. Of course, being near the equinox right now, this is where the daily changes are pretty dramatic. Even over the last week (where we have had a string of very nice, cool days - except a bit warmer yesterday) I can see a noticeable dip in the production levels.

Of course, the flip side of this is that our A/C use (particularly this year) is dropping even faster, so our net usage is actually about as good as it will get since our home electric (having gas heat and hot water) usage is now essentially at its lowest level.
 
Just playing around with PVWatts, it seems like winter production is pretty highly dependent on azimuth. I have panels facing all 4 cardinal directions, and my real system is expected to produce 33% less compared to a hypothetical all-South system of the same size in December, but about the same amount in June.

View attachment 596525
Yeah, it is a huge difference. With our solar roof split 50/50 on north and south (7/187 degree) planes, PVWatts estimates the south-facing roof to produce 535 kWh in June while the north-facing roof hits 502. However, in December, the numbers are 367 for the south-facing but only 56 for the north-facing.
 
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16kw ground mount system, just commissioned on 9/25. I’m at about 45 degrees north. Won’t really see what it can do until next May - August, but today produced 85 kw hrs.
Nice curve! As of a couple of weeks ago, I have morning shade on pole-mounts until close to Noon, although still managed 60 kW yesterday on a partly cloudy day with a 17.5kW array (7.0 & 7.7 SuunyBoys). 44° North.

Best days since Spring install were around 110kW.
 
Surprisingly, I've moved away from constantly checking my solar production multiple times a day to checking maybe once a week.

In total it has generated 3.5mWh since it was turned on in August. I seem a long way from the yearly 18.7 mWh forecasted by Tesla. Hopefully the spring and summer will offset this.

My electric usage is significantly higher due to an additional pond pump I installed prior to the solar. I must have miscalculated the kWh it is adding for the year. Not that large of a pump at 500W, but running 24 hours a day really adds up. My wife has also been running the AC more which definitely isn't helping.

Right now I "owe" SCE $300 for the extra usage.

I may end up having Tesla add another 4kW system next year if our usage continues to not match our production.


upload_2020-11-7_7-31-46.png
 
My electric usage is significantly higher due to an additional pond pump I installed prior to the solar. I must have miscalculated the kWh it is adding for the year. Not that large of a pump at 500W, but running 24 hours a day really adds up. My wife has also been running the AC more which definitely isn't helping.

500W running 24/7 is a lot of power. That’s 12kWh a day, 360kWh a month, or 4380kWh a year. Does it really need to run 24/7? Can you install a timer and only run it for 8 or 12 hours a day?
 
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Surprisingly, I've moved away from constantly checking my solar production multiple times a day to checking maybe once a week.

In total it has generated 3.5mWh since it was turned on in August. I seem a long way from the yearly 18.7 mWh forecasted by Tesla. Hopefully the spring and summer will offset this.

My electric usage is significantly higher due to an additional pond pump I installed prior to the solar. I must have miscalculated the kWh it is adding for the year. Not that large of a pump at 500W, but running 24 hours a day really adds up. My wife has also been running the AC more which definitely isn't helping.

Right now I "owe" SCE $300 for the extra usage.

I may end up having Tesla add another 4kW system next year if our usage continues to not match our production.


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I think your yearly total will come in close to what its supposed to. I think I said this up thread somewhere if I am remembering this thread properly, but our best time out here is march - Jun (the beginning of june). You wont likely be using your AC at all, and production starting around the beginning of march starts to really ramp back up.

If you got installed in August, that is one of the worst months for us out here, because of the amount of AC we normally need to use in August / September, and this year was particularly hot. I dont track it separately, I just eyeball the numbers daily in the tesla app (Its almost ritualized for me at this point, lol), mostly because I am adjusting my powerwall reserve setting to "a value that I feel will get me to the next sunny time" depending on weather, etc. Anyway, production from my system is down to about 25-27 kWh a day, or so with some drops likely on the same days you show them in your data due to clouds etc.

Contrast that with March - Jun, which for me ramps up from the lows of winter (somewhere around 20 - 22 kWh, a day or so, 30s or so in march, through high 40s by june, peaking in late june / early july to about 53-54 kWh.. but by late june we were using the AC this year.

On a side note, I thought you had a QuietCool whole home fan? That cut my AC usage by at least 2/3rds. For example, in our recent small heat spike to the low 90s this week, I didnt use AC at all. Just ran the fan for a couple hours when I got up (which is around 6:30-7am) which cooled the house down enough that we were wearing sweats inside, closed up the windows / blinds / curtains etc around 10am. It got up to 93 ish, but was comfortable for us in the house (78 ish), then, around 5 pm., I opened a couple windows for an hour and ran the fan again. and we were comfortable.

Anyway, I hear you on the pump, although I dont have a pool. I bought a really high end (and very power hungry) Sony 8K TV earlier in the year, and it also seems to consume, on average 600-800 kWh of power each hour. Our TV is on from when my wife gets up at 8am to when we go to bed (lol).

I am a big kid, so I still play a video games, and watch sports.. luckily my wife not only tolerates it but enjoys the same things I do.. I guess thats one reason I have been married for 35 years so far lmao. Anyway, this TV consumes double the power the I took out of the main room and put upstairs did, even though that one is a 4k TV. This one consumes power like a plasma tv even though it isnt, haha.

I normally wouldnt worry about the "power the TV uses" but since I can see it easily now, I know that if I had a power outage I wouldnt use this TV, we would go upstairs as that one is pretty frugal.
 
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500W running 24/7 is a lot of power. That’s 12kWh a day, 360kWh a month, or 4380kWh a year. Does it really need to run 24/7? Can you install a timer and only run it for 8 or 12 hours a day?

It is part of a 3 pond system with streams between them. There is a lot of suspended water where if the pump is shut off the bottom pond overflows. It is also good for the water quality and the fish to have the constant flow.

I do have a second pump which drives waterfalls. I've been thinking about shutting that pump off at night. But it isn't nearly as much power as the primary pump.
 
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On a side note, I thought you had a QuietCool whole home fan? That cut my AC usage by at least 2/3rds. For example, in our recent small heat spike to the low 90s this week, I didnt use AC at all. Just ran the fan for a couple hours when I got up (which is around 6:30-7am) which cooled the house down enough that we were wearing sweats inside, closed up the windows / blinds / curtains etc around 10am. It got up to 93 ish, but was comfortable for us in the house (78 ish), then, around 5 pm., I opened a couple windows for an hour and ran the fan again. and we were comfortable.

I don't have a whole house fan. It is on my todo list now that it is cooling down as I didn't want to climb into the attic in 100+ degree weather ;)
 
I don't have a whole house fan. It is on my todo list now that it is cooling down as I didn't want to climb into the attic in 100+ degree weather ;)

Just my 0.02 on this, since we have talked about it in the other thread.

If you have allergies, this may not be a good investment. I got one about 3 months ago, and I would not do it again. I underestimated the amount of dust that hangs in the air where we live, and when we run the fan on days that don't have good AQ scores, I can really tell.

If you don't have allergies, it's probably a good investment.
 
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Just my 0.02 on this, since we have talked about it in the other thread.

If you have allergies, this may not be a good investment. I got one about 3 months ago, and I would not do it again. I underestimated the amount of dust that hangs in the air where we live, and when we run the fan on days that don't have good AQ scores, I can really tell.

If you don't have allergies, it's probably a good investment.

Interesting. I do have allergies, but we are pretty good about putting fans in the windows at night. Does it seem to pull in more dust than using fans in windows?
 
Flipping this thread on its head a bit, what's the minimum generation you've seen from a working system?

Even through some big, cloudy storms, we've managed to eke out a few kWh per day at a minimum. But today we've got about an inch of snow on the panels, and my SolarEdge monitoring app is reporting a whopping 6 wh for today.