Cali central valley fun facts; The valley stretches some 450 miles long, so the comparison to az & new mexico must reference which latitude - as in northern vs the southern end of the valley because there's about a 15% sunshine difference being at one end or another - & the sunshine difference is further compound by another phenomena in the valley, besides the Sun's higher / lower azmyth .... the infamous & sometimes deadly 'Tuli-fog'. Not only does it lay waste to many a careless driver, but as it tends to have a lowering effect on PV production Just a few miles inland of Laguna Beach - we get a similar seasonal phenomena, & unfortunately it's when days are the longest. They call it the June gloom ... a heavy marine layer that carries inland every night and typically doesn't burn off till just before lunch. .
Your annual output is trending down to 12k kWh. Since you are also in Central Valley, 12k for 9.57kw system is a little lower than I would expected. Do you have trees shading the panels? My neighbor with 4.14kw generates more than 7000kWh a year.
I continue to be amazed by the relatively low drop in production on days called by weather service "partly cloudy." I get about 70 - 85% of a sunny day. Even on days called 'cloudy' I get about 50% of a sunny day. Even rainy days generate around 20% of a sunny day. I have LG panels from 2017. I don't know if this is due to tech improvements, my SolarEdge Optimizer setup, the kind of clouds we have locally, or other factors. Colorado has some of the best sun and climate for PV in the country. I collect about 7 MWh a year from a 3.78 kW array that has some shading 6 months of the year in the morning hours.
No trees shading, but think I need to get up on the roof more often to clean the panels. Our green jeep is grey after 2 weeks. iPad ?
Final production for May: 758 kWh Had 1 day of rain (unusual for May in Fairfield) 2 overcast days 2 cloudy days So room to improve. June should be better.
Money is a motivator . Not giving anymore to big oil or the monopolistic utilities is something I’ll get behind. More and more are everyday.
I’m getting ready to go solar also. A 5.5 kw system here in northern Utah. As a side note, I read an interesting article about the problem of disposing these solar panels once they run out of their useful life. The harmful materials that are being used in the construction you don’t want buried in your back yard. Anyone else heard this?
I’ll be dead and gone before my panels run out of their usefulness. Just curious how they will be disposing of them in the future and what our kids and grandkids will have to deal with .
My 30 year crystal ball is fuzzy, but I'm pretty sure that plastics and climate change will be vastly more important. Here is my first Google-fu
I think 50% is a huge drop off. Imagine if you lived where it's cloudy and rainy a lot. Solar really doesn't work there. Neither does it work with substantial tree cover. Most companies use the PVWatts code to estimate solar systems so you know what you're getting into before you commit.
<<shrug>> Each to their own. My point was that generation is greater than the percentage cloud cover would imply.
I'm certainly glad I didn't listen to similar pessimism before installing solar PV on my house: This graph was before the final expansion that put me to Net-Zero. Will post a more recent production graph next week.
On a sunny day I get around 46kWh with peak around 5.5kW, out from a 6.5kW system. But on a cloudy day the peak would be 6.1-6.4kW, so it can generate 45-48kWh if is just sometimes cloudy. In Central Valley of California, sunny day means haze and pollution and sunshine is actually partially blocked by haze.
Sunny days also mean higher panel temperatures, reducing output. Partly cloudy days allow the panels to cool when shaded. When the clouds drift away and full sun suddenly hits the cool panels, output can briefly skyrocket, until the temperatures rise.
Solar works wonderfully. However, how financially efficient it is depends upon your local utility and state rebates/incentives. I’m in Minnesota, not nearly as sunny as the west, southwest regions. Yet financially, I am paying about 1.5 cents/kWh for the next 30-35 years. I’d say that works wonderfully.