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First MWh produced! On the Solstice!

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McRat

Well-Known Member
Jan 20, 2016
5,771
6,080
LA
Came initially on line Dec 2, some shutdowns to optimize. Hit first MWh at 10:00am Pacific Dec 21 after 20 days.
Array is pointed to peak production in the Summer when power is $$$.
FirstMWhDec21-2017.jpg


Monitoring was not enabled until Dec 14, but the inverter stores total production since coming on-line.

Happy Dance!!
 
Basics:

64 panels (2 sq meter size) of 310w +5w -0w in two strings using 16 Optimizers per string (2:1) feeds into a SolarEdge SE20K-US at 797vdc, outputting up to a peak of 13kW at Solstice. Orientation is 11-15° tilt for max summer. Ballasted DynoRaxx mounting system on flat roof. I
 
Very nice. I wish I had the room for a larger system. That's among our top criteria if/when we next move. Current system is 4.2 kW via 15x280W panels. It's been up for around 3.5 years and recently passed 20 MWh produced.
 
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Very nice. I wish I had the room for a larger system. That's among our top criteria if/when we next move. Current system is 4.2 kW via 15x280W panels. It's been up for around 3.5 years and recently passed 20 MWh produced.
By the time you buy another system the watts per panel will be considerably higher. I read the other day about 500 watts per panel based on (I presume STC) 24% efficiency
 
Nice! That's quite a system, should be pumping like made during the summer peak.

* A note on that 500W panel above...I think that's the ground mounted utility scale size, not residential. Though the higher-end rooftop sized ones should be crossing over 400W per panel any day now.
 
I've only seen 325 to 350 in the last year, I don't see 400 coming that much quicker.

Yeah, cost climbs as efficiency climbs. ~325w for the 2x1 meter panels are about the best value. Smaller residential units are 1.67m x 1m and go up to about 300w at a higher cost per watt.

The jump in price right now from 16% efficiency to 19% efficiency is about 50% increase per watt.

I still have reserved inverter capacity. 20 kW is max AC net output. So I can run about 27 kW worth of panels.
I also have 2 panels that are 'blinded' by an AC unit I need to relocate. I planned everything in the summer, and the panels were not shaded in August.

I started the build in August and had a lot of headaches with my AHJ and SCE. Cost over-run was 25% for costs associated with paperwork that had no effect on safety. It was my first solar project, and I had to learn everything the hard way. :D
 
Ghetto Math:

If my cars would use gallon at the rate of 30 mpg, at the worst time of the year, I'm generating $163 a week worth of gasoline, but without the CO2 or emissions. I estimate by the summer, that will be at least $240 a week gasoline equivalent.
 
Now for the results.
Step 1 of any solar project is to first reduce your consumption. We dropped power use ~1,000 kWh
Then you install solar to assist. ~1,600 kWh for the first month.
So ~2,600 kWh reduction in power use from 2016 to 2017.

BillDec2017-2016.jpg

Orange is High $/kWh, Green is Low $/kWh. So far, far less 'higher cost' power was used in 2017. 2,750 kWh of High Cost power was used in 2016, but only 1,307 kWh was used in 2017 or more than a 50% drop in Peak TOU power.

So in 2016, non-solar, pre-optimized power use, it cost a small business $0.157 / kWh in winter.
After solar and optimization, in 2017, power was charged at $0.203 / kWh or a 29% INCREASE in price per kWh.
While this is caused by the new Demand Based Time Of Use, our Peak Demand was 19% LESS than 2016, however note that the actual Peak Demand was 12.40 kW since the 16 kW Dec17 peak was before the solar was actually active.

So even if you try to save electricity, even if you install solar, even if you reduce your Peak Demand, your power costs per kWh go up 29% for going 'green' with the new CPUC endorsed tariffs.

California's Public Utility Commission is apparently either trying to stop solar installation and energy saving technologies, or they feel Small Businesses need to be punished.
 
This is a SunPower 435w panel...

View attachment 270838

Aren't those sort of for special projects? They are larger than commercial panels (81.4" vs 77"), and very high voltage (73vdc Vmp), which limits which optimizers and lengths of strings you can use. The power per sq foot isn't much different than the 34vdc / 66" LG 335's which are only $1 a watt and easier to work with. Because the 435w are bigger, in many situations you can't get as much coverage, and shadows will affect them easier.

While you do get a <3% more power per sq ft, you probably will lose that and more due to layout limitations and greater sensitivity to shading.

If I could do it all over again, I'd have went with 66" panels even though they were more per watt. I could have gained about 10% more coverage with the 66" than the 77" panels with less shading losses. But then again, I paid like $0.79 a watt when I bought the Astroenergy panels. I went cheap and now I regret it. I could have run longer strings and got more coverage and more power.
 
Update:
Added 12 Canadian Solar panels 370w each. Balanced to two strings of 38 panels each (2 square meter each,152 sq meters, or 1,600sqft of panel surface. Finally, finished testing and brought on line 1.5 hrs ago.
On a 100% overcast day, no blue sky, looks like it's going rain, 10.8kW output at noon. Advertised rating is now 24.2+ kW
The new panels are aimed southwest to maximum output at 4 pm, effectively widening the curve.
Total production since December 2, 2017 PM is 13,500 kWh with probably 12 shut down days for inspection, relocation of shaded panels, fine tuning, SCE/AHJ inspection, and then the panel additions.