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Discussion Starter · #1 ·
I had my solar panels active for 26 days last billing cycle. Even with NEM 2 with PG&E, having solar panels with an EV is an absolute steal in California with our high electricity rates and crazy gas prices. It is up to $3.40 for the cheap gas stations in town now. The PG&E EV-A rate is an amazing deal and I will show you the math from my last bill. Note that this is for 26 days and not the entire billing cycle.

Net Usage
Peak -285.588800 kWh @$0.32987 -$94.21
Part Peak -581.342400 kWh @$0.20417 -118.69
Off Peak 517.181500 kWh @$0.13046 67.4

I know the prices per kWh are insane, but with a plan like this you need to understand that there are no tiers and you get credit for the high price that you feed the grid. I ended up with a $145.50 credit with a net 350 kWh added to the grid. That works out to $0.42 per kWh credit that I put into the grid. I have to pay $18.93 in charges from using energy from the grid with my usage, but they do subtract with estimated $10 you need to be hooked up to the grid from that value.

May starts the summer schedule that has even higher Peak usage values, I think it is $0.47 per kWh. I have my thermostat programmed to get my house down to 68 degrees before the peak hours start and then not run during peak hours. I guess if I build up enough credits it doesn't matter because I will lose them at the end of the year. However my 11.25 kWh system will be able to power my house and two electric EV's travelling 50,000 miles per year.
 

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I've always thought PV makes sense for CA consumers if they own property with a good unobstructed southern exposure. Petrol and utility rates are quite high in CA compared to the national average, and they get a lot more sunshine than most places.

So, the overproduction is "banked" for the year, and not lost every month? That would have me shooting for as near to zero net usage as possible so that I'm not paying for extra PV production.

Smart getting the bulk cooling out of the way before peak rates.
 

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Discussion Starter · #3 ·
With the way rates are from time of use, West facing panels are probably more valuable than South panels. Unfortunately I could only get 4 panels on the West because of the architecture design on the front of the house. Everything is banked until the true-up at the end of the year. I will need credits going into X-mas season because I am slowly turning my house into the Griswold's. I also built the system to accommodate another EV, so this year I will end up with a crazy amount of unused credits that will be lost.
 

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... so this year I will end up with a crazy amount of unused credits that will be lost.
Whoa, it is my understanding that California utilities must PAY YOU for all excess power your panels generate:

At the end of the year, all the kWh that were sent to the grid are subtracted from all the kWh that the customer used, and a final bill called the “true-up” is due. If your solar system is sized to meet your usage and you hit that number, your true-up bill could be $0. If you used more than you sent to the grid, you have to pay for the balance. If your panels made more than you used all year, you get about 3-4 cents per kWh for the extra.
Has something changed?
 

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Discussion Starter · #5 ·
Whoa, it is my understanding that California utilities must PAY YOU for all excess power your panels generate:Has something changed?

The EV-A rate is kind of weird how it works if you charge your car during the off-peak hours at night. At the end of the year I will probably have used more kWh than my system generated. However, because of the higher rates during peak hours I could end up with a $500 credit that will be lost. NEM 2 will only give you credits for net energy produced. I could use 20,000 kWh and produce only 18,000 kWh, and end up with a large credit due to time of use. In the example I used 2000 more kWh than what I produced, the credit does me no good.
 

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I just finished my third year of NEM in SoCal. If you're into playing the game, it can be fun and profitable to time your usage to take advantage of the rate teirs. Getting credits at peak and using off-peak you can wind up with a zero bill even though you use a lot more than you generate. Balances get carried forward and at the end of the year they true up. If you generate more than you use you do get paid for it, just not at the full retail rate. If you used more than you generated but have a credit from playing the time-of-use game, you're done - the massive credit goes away, but your bill is zero. And if you used more than you generated and don't have a credit, you pay the full balance. In my first two years I got a check because I produced more than I used. Then I got the Bolt and became a 2-EV household and I actually had to pay for year 3.

If I were installing solar now I'd probably favor western exposure over southern. Most time of use rates now have 2-8pm as the peak hours, making evening production more valuable than mid-day.
 

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Just remember that PG&E will only pay you 'commercial rates' for any excess production you have generated at your annual 'true up'. After all of the electricity you have used is subtracted from all of the electricity you have generated over the course of the full year, they will pay you only 2.6 cents per kWh for your surplus.

I encourage anyone considering installing solar panels to utilize the services of a reputable solar panel installer. They will map your roof and calculate the best panel layout for you. They will also evaluate your electricity bill and determine how much capacity you need to achieve the best payback. Let's face it: at 2.6 cents per kWh, you will never realize a return on your investment in any excess production.

I have 22 panels (7.4 kW peak), and I'm loving it. Payback will take 7 to 8 years, then the power is FREE.
 

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Just remember that PG&E will only pay you 'commercial rates' for any excess production you have generated at your annual 'true up'. After all of the electricity you have used is subtracted from all of the electricity you have generated over the course of the full year, they will pay you only 2.6 cents per kWh for your surplus.

I encourage anyone considering installing solar panels to utilize the services of a reputable solar panel installer. They will map your roof and calculate the best panel layout for you. They will also evaluate your electricity bill and determine how much capacity you need to achieve the best payback. Let's face it: at 2.6 cents per kWh, you will never realize a return on your investment in any excess production.

I have 22 panels (7.4 kW peak), and I'm loving it. Payback will take 7 to 8 years, then the power is FREE.
Yup. Since my cost per kWh over the life of my 5kW PV system is ~.10/kWh, it doesn't make sense for me to offset Tier 1, which is slightly less than that. So my system was sized to offset Tier 2, at $.25/kWh.

At true-up, SCE pays the going wholesale rate, which for me in 2016 was $.02/kWh. It would be stupid for me to pay for a system that produces surplus under these conditions. I'd be losing $.08 for every kWh I produced.
 

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Agree with BoltyMcBoltFace. My first array is 16-17 yrs old & south facing, designed for max production. But the second array, put in to power the Bolt, is designed to operate during peak metering (basically afternoon to early evening) by facing west. It has worked like a charm. Two discoveries, I did not understand or fully appreciate the Bolt's ability to delay charge in order to take advantage of the super off peak overnight rates, and second, how much cheaper SCE rates are than PG&E. Not clear why PG&E rates are so much higher than SCE.
 

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Honestly I need to get off the pot and put in Solar, I have a pretty great house for solar with lots of South AND West facing roof.



I do have some trees partially blocking the largest expanse of West facing roof but considering that's a ~2400 sq ft house with a ~400 sq ft garage it's still a lot of roof space.

My plan is to put in as many panels as I can afford prioritizing the West side.
 

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Discussion Starter · #11 ·
The problem with your roof is all the slopes. With fire codes you need to leave a 2 foot walking path so some of those smaller areas you may not be able to put any panels. I would get a few quotes and surveys. My payback for solar is about 5 years, but I live in the Central Valley which may be one of the best places to have solar in the US. That area with shade looks like an ideal place for a nice array, might need to get that chainshaw out ;)
 

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Honestly I need to get off the pot and put in Solar, I have a pretty great house for solar with lots of South AND West facing roof.



I do have some trees partially blocking the largest expanse of West facing roof but considering that's a ~2400 sq ft house with a ~400 sq ft garage it's still a lot of roof space.

My plan is to put in as many panels as I can afford prioritizing the West side.
Suggestions for ya.... remove vent pipes from your roof and instead use air admittance valves. Then your panels won't have to skip over where the vent stacks are at. Also, fire code requres a 3' setback from all edges and 18" at the ridge of roof for solar panels... to allow the fire dept to ventilate your roof if needed. Hips need 18" on either side, valleys need 3' on either side (I think). Complex roofs sure look great, but they are tough for solar installs.
 

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I encourage anyone considering installing solar panels to utilize the services of a reputable solar panel installer.
Question: When you say "reputable solar panel installer", do you mean a full service provider that will do everything? Plan the system, pull the permits, sell the panels and hardware, sell the inverter(s), and perform the labor?

My plan is to put in as many panels as I can afford prioritizing the West side.
Question(s): What is your annual average kWh consumption now and in the foreseeable future? What are the dimensions of the long rectangular roof area facing West? Is the garage roof 20' x 20'? Is your pool filter system/pump system fairly new/modern? What is your homes roof pitch?
 

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Just a general warning about solar installers.... many companies only do the front end work... permits, spec'ing the job, collecting your money. They sub out the install. Horror story du jour.... coworker got solar with one such company. They said XX number of panels on the roof. When the installer got there, he said they couldn't fit that many on the south roof, so moved them to the north roof (shallow pitched roof). The result is the panels don't perform well at all, so he's not saving money on electric. And he's got roof leaks but the company he paid says they aren't responsible. He's round and round with them and going to have to sue in court.

Its all about incentives.... a reputable company will guarantee a certain production and pay you the difference for a few years if it doesn't produce what their model said. If my coworker had this guarantee, the front end company would be very interested in fixing his problems.

We went with Southern Energy Management out of North Carolina. They came in wayyyyy under $4/watt. They guaranteed 22MW and their system made >25MW last year. I'm not affiliated with them in anyway other than I told them I'd give them a good word when I could. My review is on google, I am listed as Wes Johnston there. https://www.google.com/search?clien...n+energy+management+reviews&ie=UTF-8&oe=UTF-8
 

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FYI - love the plan - there is a new fire regulation that requires 3 foot set backs from peaks and edges of the roofs - keep that in mind when planning for solar panels and the number of panels you can fit.
 

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shotel said:
What is your annual average kWh consumption now and in the foreseeable future?
21809 last year, will probably go up a bit thanks to the Bolt and will go up a bit more in 2019 because my eldest will be coming home from the Navy and going to college while living at home.

What are the dimensions of the long rectangular roof area facing West?
IIRC about 20x50 for that section of the house (that part was added on about 7 years ago) so I'd guess ~12x50 for that side.

Is the garage roof 20' x 20'?
Yes

Is your pool filter system/pump system fairly new/modern?
Mostly, it's about a 5 year old system but it's one of those variable speed ones that runs at high speed for an hour and low speed for 8 hours.

What is your homes roof pitch?
Never measured it but it looks like this:

 

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Question: When you say "reputable solar panel installer", do you mean a full service provider that will do everything? Plan the system, pull the permits, sell the panels and hardware, sell the inverter(s), and perform the labor?

That's probably the best option for most people. Get a company that's been around for a while and can do everything. I went with Sunrun.

Another option would be much more DIY. Get an overall design (one that includes a full assessment of your usage, number of panels and the angles they'll be mounted, shade, etc.) then have a roofer install the racking because they'll do it right, then an electrician to wire everything.

And be incredibly wary of zero-down PPA lease deals - most of them are basically scams to fleece people by offering to drop their bill by a few bucks a month but lock them into an ugly long-term contract. That said, not every lease is horrible. I did one myself, but I paid the whole thing up front for the same cost as buying it outright (including the tax credit). I liked that they insure and maintain the system, so if the inverter fails or a panel gets cracked, they fix it.
 

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320.67 last year, will probably go up a bit thanks to the Bolt and will go up a bit more in 2019 because my eldest will be coming home from the Navy and going to college while living at home.
Starting with the L.A. County Fire code as it pertains to rooftop Solar Panels

3. Smoke Ventilation:
a. Panels/modules shall be located no higher than 3-feet below the ridge.
b. The panels may be located no higher than 18-inches below the ridge if photovoltaic
panels are installed only on one side of the ridge.
c. Arrays shall be no greater than 150-feet by 150-feet in distance in either axis.
~ https://www.ladbs.org/docs/default-...nt-96-solar-photovoltaic-system.pdf?sfvrsn=12

Using the Western ridge-side 10' x 50' roof (I'm assuming 1/2 of a 20' x 50' area), and citing the Fire code which seems to allow for only a 18" space from ridge peak to Panel when using just one side of the roof...

...you can fit 15 x 350W panels in portrait = 5.25kW

On the South facing Garage roof, you can get another 6 x 350W panels = 2.1kW

On the South facing home roof, I'm guessing you can easily place another 6 x 350W panels without any costly PIA re-routing of exhaust vents = 2.1kW

That totals up to a 3 or 4 string 9.45kW system, which is probably the maximum nameplate output you will be allowed to put on a residential roof (from my understanding the max is 10kW).

This system would probably (ball parking it) generate 2.25 X the total energy you consume now.

Because of the tree shading I would go microInverter. 27 350W panels + hardware + Inverters + permits + labor. After the Federal ITC tax credit, you can do this for about $15K.

A good resource to estimate with: https://pvwatts.nrel.gov/
 

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Another option would be much more DIY. Get an overall design (one that includes a full assessment of your usage, number of panels and the angles they'll be mounted, shade, etc.) then have a roofer install the racking because they'll do it right, then an electrician to wire everything.
^ ^ ^ ^
***This****
@raitchison can do the design/layout. @raitchison can purchase all the hardware. @raitchison can contract a licensed/bonded Electrician (the hard part) to be his GC. By the time his oldest graduates university the system will have likely paid for itself.
 
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