10Kw Arizona System Advice

[sogorman]

Hello all, I am hoping to draw from all of your wisdom and knowledge. I am looking to spin up a 10Kw system fro my house in Phoenix, Arizona and I have a few questions for all of you.

First have any of you had any experience buying a system and hiring a installer for the permitting and install process? (i'm going to pay out of pocket and not lease so I'm trying to save a few bucks) I am looking atxxxxxxxxxxxxxx and wanted to see if any of you had any experience with them? The system will cost about $19k with the panels, inverter and racks. If I went this route about how much should I budget for install and permitting?

Second question is about how many 'production hours' you see on a south facing system in phoenix? I am using 5.5hrs so a 10Kw system would produce 20,075 Kwh a year. Does this sound about right?

Thank you so much for your help, I have enjoyed following this group and I'm excited to spin up my system!

Commercial link removed

[Volusiano]

Hi Sean,

I'm also from AZ and I had an 11 kw system installed a little over a month ago. I didn't go the route of buying a system then hiring an installer to install it for me. I just got quotes from licensed installers directly and went with the most competitive installer, which is the normal route most people go with. Normally the kits like what you're looking at are for the DIY folks. I'm not sure if you can find licensed installers to install a kit for you. Normally they would prefer to recommend and use components of their choice rather than install a kit they don't have any say on. I'm not sure if you'll really save any money from buying your own kit and hiring an installer just for labor work only. Even if you find somebody to install your kit of choice, you should try to get complete quotes from the one-stop-shop installers as well. I'll bet you that the difference won't be that far off. And with the one-stop-shops, it's much easier to file warranty claims with them later on if you have a problem. It's one thing if you're already very familiar with the whole process to try to DIY. But if you're not, I'd recommend you leave it to the pros.

I assume that you've already done your homework to determine that you need a 10 kw system. Many here will tell you to try to conserve first then only size to what you need after you've already conserved to the max. And it'd be wise to follow that advice.

Regarding your question about annual production estimate, try to google "pvwatts" which is a tool that can help you estimate your annual production based on your location and configuration.

Regarding choosing components, you should learn about the pros and cons between central inverters and microinverters and optimizers first (google the great microinverter debate). Unless you have shading issues, it's not advisable to put electronics like microinverters or optimizers up on your roof top in AZ weather. The hot roof top in the summer is going to be enemy #1 to any electronics on your roof top.

You didn't say if you're with SRP or APS. If APS, I assume you're aware of the on-going controversy with APS wanting to tax solar customers monthly fees to the tune of $50-$100/month. The Arizona Corporate Commission voted last Thursday to tax solar customers who install after this year $0.70/kw monthly for their system. A 10kw system would be $7 solar fee/month. It's a far cry from the $50-$100/month APS wants to see, but this rate is subject to change later on as well. Only grandfathered solar customer with system installed on or before 12/31/2013 would be exempt from this fee.

[sogorman]

Thanks for the information Volusiano! If you don't mind me asking who did you end up with for your system? Also are you able to monitor your system? If so how many KWh did you produce in the last 30 days?

Yes I am well aware of the APS/ACC meeting, I had the web stream on at work for the two days. I'm not sure what the future will hold but with an electric car I still want to go solar to get 'off the grid' as much as possible. Maybe some day double the system and get a whole home UPS!

Going to check out the link you recommended now!

Sean

[Ian S]

Hello all, I am hoping to draw from all of your wisdom and knowledge. I am looking to spin up a 10Kw system fro my house in Phoenix, Arizona and I have a few questions for all of you.

First have any of you had any experience buying a system and hiring a installer for the permitting and install process? (i'm going to pay out of pocket and not lease so I'm trying to save a few bucks) I am looking at www.solarwholesalers.net and wanted to see if any of you had any experience with them? The system will cost about $19k with the panels, inverter and racks. If I went this route about how much should I budget for install and permitting?

Second question is about how many 'production hours' you see on a south facing system in phoenix? I am using 5.5hrs so a 10Kw system would produce 20,075 Kwh a year. Does this sound about right?

Thank you so much for your help, I have enjoyed following this group and I'm excited to spin up my system!

Sean

Hi Sean - Our sponsor is a solar sales company - competing links are not allowed

Yes, I suppose you can save some bucks with D.I.Y. but remember, if and when something goes wrong, there'll be a lot of finger-pointing as to who is at fault. I also think you might have trouble finding a good experienced installer who will just happily go with what you opt to buy over the internet. You will also need permits, an electrician and both the city and utility will have to sign off on the system. Yeah it can be done but there will be more headaches for you.

As for production with a southern azimuth, PVwatts is fairly accurate as long as you go with a higher derate factor: 0.85 or so seems to be working for me. My 6.9 kW Sunpower system here in Phoenix had a first year production of about 12,400 kWh so you can probably do the math to see what you might achieve; it's not going to be 20,000 kWh. Note production hours is kind of meaningless since on a clear day your power vs time looks a lot like a bell curve so you have to integrate under it to determine the kWh. Again PVwatts is a good tool but their derate factor is way too conservative at least for my system.

[Volusiano]

Thanks for the information Volusiano! If you don't mind me asking who did you end up with for your system? Also are you able to monitor your system? If so how many KWh did you produce in the last 30 days?

Just PM'ed you on this.

[Volusiano]

I'm not sure what the future will hold but with an electric car I still want to go solar to get 'off the grid' as much as possible. Maybe some day double the system and get a whole home UPS!

Oh yeah? Which electric car do you have? I have a 2013 Chevy Volt myself. Used to have a 2011 Nissan LEAF but AZ is too hot for its uncooled battery without active TMS liquid cooling. Lost more than 15% battery capacity in first year of use, so I sold it back to Nissan and got a Volt instead. The electric car is part of the reason that prompted me to go solar.

I assume when you said above "to get 'off the grid' as much as possible" is just a figure of speech to not use electricity from the grid, but not to literally "get off the grid" as in not be tied to the grid, right?

[sogorman]

I have a Ford Focus Electric, went this route specifically because of the Phoenix heat and Ford's active TMS.

Yes the 'off the grid' shouldn't be taken in the literal sense, just trying to reduce my load (just got done replacing all my bulbs with CREE LEDs) and generating as much as I can during the day to offset my load at night.

[FUN4ME]

You didn't say if you're with SRP or APS. If APS, I assume you're aware of the on-going controversy with APS wanting to tax solar customers monthly fees to the tune of $50-$100/month. The Arizona Corporate Commission voted last Thursday to tax solar customers who install after this year $0.70/kw monthly for their system. A 10kw system would be $7 solar fee/month. It's a far cry from the $50-$100/month APS wants to see, but this rate is subject to change later on as well. Only grandfathered solar customer with system installed on or before 12/31/2013 would be exempt from this fee.

I see you are talking about Arizona, does anyone know if California (SCE) has anything like this in the works? and how far out is it?
Thanks Erich

[Volusiano]

I see you are talking about Arizona, does anyone know if California (SCE) has anything like this in the works? and how far out is it?
Thanks Erich

I don't know the answer for this since I'm in AZ, of course. But from what I hear, this issue is fairly new and all eyes were on AZ to see what the outcome was going to be since it'll set a precedence for other utility companies in the country to follow. The Arizona Corporate Commission deliberated this very carefully because they knew all eyes were on them. The vote was a close 3 to 2 for the $0.70/kw monthly. 2 out of the 3 commissioners thought that the $0.70/kw was too low.

In doing so, they acknowledged that there's a cost shift from solar customers to non-solar customers like APS claims. However, they recognized that $50-$100/month fee like APS wants would kill the solar industry in AZ for sure, so they compromised by going for the $0.70/kw monthly fee. Even at that rate, that will probably kill the monthly lease market already since most people only save $5-$10/month between their monthly solar lease payment vs their utility bill according to the local solar leasing companies.

[FUN4ME]

Setting a precedence, that's what worries me.

[J.P.M.]

I don't know the answer for this since I'm in AZ, of course. But from what I hear, this issue is fairly new and all eyes were on AZ to see what the outcome was going to be since it'll set a precedence for other utility companies in the country to follow. The Arizona Corporate Commission deliberated this very carefully because they knew all eyes were on them. The vote was a close 3 to 2 for the $0.70/kw monthly. 2 out of the 3 commissioners thought that the $0.70/kw was too low.

In doing so, they acknowledged that there's a cost shift from solar customers to non-solar customers like APS claims. However, they recognized that $50-$100/month fee like APS wants would kill the solar industry in AZ for sure, so they compromised by going for the $0.70/kw monthly fee. Even at that rate, that will probably kill the monthly lease market already since most people only save $5-$10/month between their monthly solar lease payment vs their utility bill according to the local solar leasing companies.

I'd suggest that CA also has something to do w/kicking in the door on monthly (sur)charges on net metering since AB 327 passed last month will allow CA POCO's to charge "up to" a flat $10.00/mo. in the future. On the diff. between lease vs. bill: Why such a small amount between the lease payment and (assumed average) savings on their utility bill ?

[FUN4ME]

I'd suggest that CA also has something to do w/kicking in the door on monthly (sur)charges on net metering since AB 327 passed last month will allow CA POCO's to charge "up to" a flat $10.00/mo. in the future. On the diff. between lease vs. bill: Why such a small amount between the lease payment and (assumed average) savings on their utility bill ?

Thanks, I guess i will have to look that up (AB 327) and do some reading tonight.

[J.P.M.]

Thanks, I guess i will have to look that up (AB 327) and do some reading tonight.

It's a great read. 1st time through took me 45 min. Be the 1st kid on you block.

[Volusiano]

On the diff. between lease vs. bill: Why such a small amount between the lease payment and (assumed average) savings on their utility bill ?

I don't know. I'm surprised to learn that myself. I was watching part of the second day of the hearing myself online and I happened to catch this part where the solar industry rep told the commissioners that their $5/month increase would pretty much wipe out the lease market. He didn't elaborate on why the saving is so small. You never know, they might have played down the numbers for the hearing to their advantage, too.