Make the switch to solar?

[J.P.M.]

Northern Illinois presents challenges. Here in San Diego, it is a different story. Our system produced 8,046 kWh of electricity for 2022. The average cost of electricity in San Diego for 2022 was $0.37/kWh. Based on this information, our system produced $2,977.02 of electricity for the year ($284/mo). When you consider that our out-of-pocket expense for the system was $10,575 after the 30% Federal tax credit (.70 * $15,107), it is not unrealistic for our payback period to be around 3.5 years. So, we've earned around $4,500 in the 1.5 years since the system cost was recovered. Not a bad investment.

Thank you for keeping your average cost of a kWh of electricity in perspective and context.

Q: Did your system produce more or less electricity than your residence consumed for 2022 ?

Reason for asking: Just pointing out that over production by oversizing an array or for that matter any excess generation by an array reduces the value of the array produced energy.

[slinthicum]

My system was designed to meet our estimated electrical consumption. With a "true-up date" of January 19th, I closely monitor for excess production. This year I turned on the electric fireplace and a space heater for warmth production, reducing natural gas consumption. This was a wise decision with the cost of natural gas for heating at an all-time high. BTW, 8,046 kWh yearly production is a little ahead of the previous 4-year production numbers. I guess that means not cleaning the panels is OK.

[slinthicum]

BTW, another key approach that has enabled me to manage electric power consumption is detailed in a "guest blog post" I wrote for Emporia Energy's blog titled "Making Data Driven Decisions on Time-of-Use Electrical Consumption".

[J.P.M.]

BTW, 8,046 kWh yearly production is a little ahead of the previous 4-year production numbers. I guess that means not cleaning the panels is OK.

Perhaps, but it more likely and also means your site had more irradiance for that period than might be expected.
My 365 day running total site irradiance is up a bit from prior years. I'm not at my n. county residence (zip 92026) just now, but if memory serves, the 365 day running total array production at that site is also up by ~ 2% or so. I've hosed the array about every 4 weeks or so since I stopped taking daily fouling measurements and accept an average fouling rate of something like maybe 2% - 3 %.

Also, and a bit further off topic, if I don't hose the array, my experience and measurement has led me to conclude that my array's fouling rate is roughly ~ 0.75%/week depending on weather conditions if it doesn't rain but that fouling rate/pattern tends to be somewhat asymptotic, leveling off at about an 8% production penalty +/- some during the long summer rainless periods.
A decent rain - maybe 1/4" or more of precip. tends to restore about 2/3 - 3/4 of the performance that was lost to fouling.
Your array's fouling trend/pattern may be similar.

My results seem to have reasonable agreement (IMO only) with other open-source data on array fouling. This is not an exact science.

[slinthicum]

The chart below reflects the reason so many SDGE customers are upset with their energy costs. What concerns me is the result for those neighbors who do not have the financial means to afford the installation of a solar system and the negative consequences they face in terms of carrying the results of higher energy costs because people like me, no longer have that expense. That unfairness I suspect will ultimately result in a NEM 4.0 designed to level the playing field for all. Hence my belief that things will change in the not-too-distant future. Thoughts?

SMUD Comparison.png

[SunEagle]

The chart below reflects the reason so many SDGE customers are upset with their energy costs. What concerns me is the result for those neighbors who do not have the financial means to afford the installation of a solar system and the negative consequences they face in terms of carrying the results of higher energy costs because people like me, no longer have that expense. That unfairness I suspect will ultimately result in a NEM 4.0 designed to level the playing field for all. Hence my belief that things will change in the not-too-distant future. Thoughts?

SMUD Comparison.png

Wow. Some of those are very high. I did a quick calculation using my rate and 750kWh would cost me less then $100. I can see why those that live in areas that same amount of kWh would cost more than $200 can easily justify solar.

[J.P.M.]

The chart below reflects the reason so many SDGE customers are upset with their energy costs. What concerns me is the result for those neighbors who do not have the financial means to afford the installation of a solar system and the negative consequences they face in terms of carrying the results of higher energy costs because people like me, no longer have that expense. That unfairness I suspect will ultimately result in a NEM 4.0 designed to level the playing field for all. Hence my belief that things will change in the not-too-distant future. Thoughts?

SMUD Comparison.png

The CA CO-OPS are much cheaper. The Imperial Irrigation District (IID) which is my power provider for my Coachella Valley residence sent my last bill of 334 kWh for $66.48 = $0.19904/kWh (with no PV) which is similar to the SDUD rate.

Using my last SDG & E period usage rates for my n. county San Diego residence, that same 334 kWh usage under schedule DR (tiered rate) would have been ~ $151.00., or ~ $0.4521/kWh. My actual usage for that San Diego residence was 654 kWh which, without the PV array on the roof would have been billed at $319.04 or ~ $0.48783/kWh.

[slinthicum]

I posted the chart above on Reddit this morning and in 12 hours it has been viewed 5,500 times. See https://www.reddit.com/r/sandiego/co...solar_in_sdge/

[RichardCullip]

Yes, in SDG&E country solar can be a very wise choice. I paid cash for our modest 4kW solar system back in early 2019. So far I'm currently 9 months into my yearly true-up period and have used a total of 5,595kWh which, without solar, would have cost me $2,406.44. With solar I'm a modest net producer and, if billed today, SDG&E would owe me $49.98.

[OCJ]

I posted the chart above on Reddit this morning and in 12 hours it has been viewed 5,500 times. See https://www.reddit.com/r/sandiego/co...solar_in_sdge/

I saw that thread and responded. The proper action I believe is to reduce profits. What other business when faced with declining usage of their product or customer loss is still entitled to the same profits? Most businesses have to adjust their profit expectations downward in those conditions.

[Shemp]

I read the dummies book and have 2 additional consultations scheduled for today. We are also looking for an EV to offset our $360/month car gas bill. I'll post some quotes when I get them.
Thanks again

btw, I'm not sure how to ask about the REC's? What specifically will they offer?

[Mike 134]

I read the dummies book and have 2 additional consultations scheduled for today. We are also looking for an EV to offset our $360/month car gas bill. I'll post some quotes when I get them.
Thanks again

btw, I'm not sure how to ask about the REC's? What specifically will they offer?

If you haven't studied this I'd highly recommend you do
Solar Info – Illinois Shines

Have you run the PVwatts program yet? Ask your 2 vendors what numbers they come up with?

Here's an example for my place I'll generate 9000KWH a year multipled by 14 years to account for losses over 15 years and I'll generate 126 RECs. times $82.26 equals $10364.76. That's money that should go in your pocket. Plus the 30% federal credit.

I'll be curious what you post later today about how they handle the presentation.

Keep in mind they most likely work for one of two companies:

Duey, Cheatem, & Howe or
Flim, Flam, & Fleecem.

Old timers will know what show those names came from.

[Shemp]

I have 2 firm quotes but am changing them to increase the size due to purchasing an EV soon.

Company 1 (Pearl Certified, local)

OPTIMIZER OPTION
12.8kW System (16,537kWh)
"32" Qcells Q.PEAK DUO BLK ML-G10 400
"32" SolarEdge Technologies Inc. S440
SolarEdge Technologies Inc. SE10000H-US
Total Cost $45,626
Fed tac credit 30% $13.7k
REC $15.2k
Net total $16.7

STRING INVERTER
13.44kW System (16.,944KwH)
"28" Q cell 480W
"2" GoodWe GW6000A-MS (240V)
Total cost $40.5k
Fed tax credit $12.1k
REC $15.6k
Net total $12.7k


Company 2

Same size system and same panels as optimizer above. String inverter.
Iron Ridge Shingle roof Solar Panel Mounting System
Fronius Primo 10kW Grid tie inverter ($5.4k)
Total cost $31398
Fed tax credit $9.4k
SREC est $19.4k
SREC fees $2.9k(15% on top of 5% collateral already added in total cost for SREC)
Net SREC $16.5k
Total Incentives $25.9k
Net Total $5.5k

Company 3

11.5kW system
"34" JA Solar JAM60510-340/MR
"34" Enphase IQ8-60-2-US
He didn't break down the costs
Total cost $35k
Fed tax credit $10.5
Net cost $24.5K
He never mentioned REC's This was my first bid and he hasn't returned an email asking for specifics. Assuming the same REC of about 16, net cost = $8.5k



I don't know how much I'm saving due to a non apples to apples approach but I appreciate company 2 quoting me a string inverter system. Everyone else pushed micro's or optimisers and from what I've read, are completely unnecessary in my situation. I will have no shade, ever!

I'm wondering why the REC's from company 1 to 2 is different by $1.3k?? The way I understand this is that a vender, in this case Carbon Solutions, gets the RECs as they are generated. They charge a 5% of the estimated SREC value (collateral fee) to the total cost and then an additional 15% taken from the check they send you in 12 months. 10% ($1942) collateral fee is refunded after the 15th year.

I'm waiting for quotes from all 3 on a string inverter system of approx 20kW DC.

[Shemp]

I forgot to add I ran PVwatts and it calculated 12.6 kW - 35 Panels. Doesn't go into specifics I guess

[Mike 134]

I have 2 firm quotes but am changing them to increase the size due to purchasing an EV soon.


He never mentioned REC's This was my first bid and he hasn't returned an email asking for specifics. Assuming the same REC of about 16, net cost = $8.5k



I don't know how much I'm saving due to a non apples to apples approach but I appreciate company 2 quoting me a string inverter system. Everyone else pushed micro's or optimisers and from what I've read, are completely unnecessary in my situation. I will have no shade, ever!

I'm wondering why the REC's from company 1 to 2 is different by $1.3k?? The way I understand this is that a vender, in this case Carbon Solutions, gets the RECs as they are generated. They charge a 5% of the estimated SREC value (collateral fee) to the total cost and then an additional 15% taken from the check they send you in 12 months. 10% ($1942) collateral fee is refunded after the 15th year.

I'm waiting for quotes from all 3 on a string inverter system of approx 20kW DC.

Thanks for the update. Interesting that company 3 "forgot" to add in the RECs to your bottom-line cost.