Lowest Achievable CPW Installed @10KW (rooftop)?

[sunnyguy]

I'm looking for a ~10KW system for residential rooftop in southern AZ. What would you say is the lowest achievable CPW installed if I do as much leg work as possible on my own?

For example, I see some 10KW kits approaching $1/W which don't include racking/mounts or misc electrical.

It seems like racking and mounting is doable for $50 per panel or ~$0.20/W

Misc electrical $1000 or $0.10/W

Permits/fees - ??

Labor - ??

Thanks

[DanS26]

I'm looking for a ~10KW system for residential rooftop in southern AZ. What would you say is the lowest achievable CPW installed if I do as much leg work as possible on my own?

For example, I see some 10KW kits approaching $1/W which don't include racking/mounts or misc electrical.

It seems like racking and mounting is doable for $50 per panel or ~$0.20/W

Misc electrical $1000 or $0.10/W

Permits/fees - ??

Labor - ??

Thanks

If you are willing to do EVERYTHING and willing to do the research and mind the learning curve, you should be able to build a grid tied system for less than $1/watt after tax credits. That assumes you do not need a service panel upgrade.

Forget the kits and buy quality stuff on eBay (yes, you can find quality stuff on eBay, but you have to do your homework). Before you buy anything have a plan and stick to it. Get a lot of quotes, time well spent and will save you hundreds or thousands.

You have to understand the NEC code. If you are not willing to do that then forget it. Dangerous stuff if you do not follow code. After you understand the code, then you have to talk to you local code enforcement people and get their OK on your plan. They are usually willing to help in most jurisdictions.

Tackle the project one step at a time and take your time to do quality work. Stop if you are not sure, research and ask questions.

Is your roof ready? If you have to replace your roof then $1/watt is not doable.

Good luck. A true DIY'er is not intimidated just because a project is complicated.

[sunnyguy]

Thanks for your reply. I will check out what is on ebay.

I realize there are a lot of things to get exactly right and a lot of options that require careful choices. But it sounds like fun to me! (Famous last words)

However since the labor is cost reduced by the tax credit there is a point at which I would say "not worth it" for a great deal on an install. What are some of the lowest CPW installs (not cringe-worthy) that people have gotten?

[sdold]

My 4kw system with Enphase M215s on a concrete tile roof cost $8000 for everything incl. Permit, tax and shipping. Renesola 250 watt panels, prosolar rooftrac rails. I think if you take the cost of panels and inverters and add about another 2/3 Of that to the total, it will be fairly close.

[sunnyguy]

My 4kw system with Enphase M215s on a concrete tile roof cost $8000 for everything incl. Permit, tax and shipping. Renesola 250 watt panels, prosolar rooftrac rails. I think if you take the cost of panels and inverters and add about another 2/3 Of that to the total, it will be fairly close.

Interesting. Was that a DIY cost or pro installed? I see a similar system on gogreen for ~$7k without permits etc...

[sdold]

Interesting. Was that a DIY cost or pro installed? I see a similar system on gogreen for ~$7k without permits etc...

That was DIY. The cost of the J boxes, conduit, breakers, wire, etc really adds up. Stuff most people don't think about until they are well into the project.

[sunnyguy]

That was DIY. The cost of the J boxes, conduit, breakers, wire, etc really adds up. Stuff most people don't think about until they are well into the project.

Gotcha. The micro inverters or power optimizers add $0.30-$0.40 to the cost of a string inverter system. I'm sure there have been discussions on when this is worth the extra expense so I will search for them. But if anyone has handy bookmarks please share.

Also, if anyone has any links to DIY experiences in Phoenix, please share. Permit and interconnect agreement require contractor listing and finding someone that is willing to work with a DIY may be an issue.

[sunnyguy]

I still haven't found any great resources on when the extra cost of $0.30/w for power optimizers is worth it vs string performance.

[sunnyguy]

I'm going to send a post to HX_Guy for some insight on local issues.

[oilerlord]

I'm going to send a post to HX_Guy for some insight on local issues.

I was just about to suggest that you look up some of HXguy's posts. He ran into a lot of issues with an installer, and basically was left with re-doing the project on his own. He's got a 78-page thread that is informative, and strangely enthralling at times - sort of watching a train wreck in progress. In the end, (and to his credit) he got it all sorted out.

After watching a lot of YouTube videos, I had considered DIY on my project coming up in May but honestly, I just don't have the time and especially after reading just how easy it is for a PV project to go wrong; i figured it was best just to hire someone that knows what they are doing. Still, I've spent a lot of time researching solar projects on my own and will be very much involved in my installation. Someone told me that a many folks are "blissfully unaware" and merely take a leap of faith by trusting everything to the installer. Considering that HXguy's "guy" came with good references in the beginning, if he wasn't involved - there's a good chance his house may have burned to the ground due to the installer's incompetence.

Another thing to keep in mind (that I've learned from hanging out on this site) is chasing the cheapest deal at the expense of quality and / or a fly-by-night installer. If a quote seems too good to be true; it probably is. Where I live (Edmonton, Canada), we don't have any subsidies so shopping around is a necessity. PV prices are roughly double than that in the US, so for those reasons; if I wanted to keep my ROI reasonably short I needed to find low cost panels. I picked up 9.45kW of used SunPower panels at under $0.45 per watt I also found an installer that is as excited as I am in having my project turn out as best as possible. His firm is relatively new but he's an engineer and has a master electrician on staff. My project is his largest so far, and he'll be using it as his reference installation to show other customers. In the last two months, he's answered at least 50 emails from me and has provided several possible PV designs free of charge.

Good luck!

[Ben25]

I installed my 10.92kw system for $9,350 after tax credits and incentive. Cost of all materials and wiring was $16,500 from our supplier, and I paid my helper $300 for a weekend. There are no permits or inspections required here, and all you need to apply for is a Certificate of Public Good, which they never deny you.

Ben

[russ]

Often you get what you paid for

[Ben25]

Often you get what you paid for

Yes. A very well installed system done by a reputable company and experienced installer.

[sunnyguy]

I installed my 10.92kw system for $9,350 after tax credits and incentive. Cost of all materials and wiring was $16,500 from our supplier, and I paid my helper $300 for a weekend. There are no permits or inspections required here, and all you need to apply for is a Certificate of Public Good, which they never deny you.

Ben

That sounds pretty good. I'm going to send you a PM for more details. Thanks.

[sunnyguy]

I was just about to suggest that you look up some of HXguy's posts. He ran into a lot of issues with an installer, and basically was left with re-doing the project on his own. He's got a 78-page thread that is informative, and strangely enthralling at times - sort of watching a train wreck in progress. In the end, (and to his credit) he got it all sorted out.

After watching a lot of YouTube videos, I had considered DIY on my project coming up in May but honestly, I just don't have the time and especially after reading just how easy it is for a PV project to go wrong; i figured it was best just to hire someone that knows what they are doing. Still, I've spent a lot of time researching solar projects on my own and will be very much involved in my installation. Someone told me that a many folks are "blissfully unaware" and merely take a leap of faith by trusting everything to the installer. Considering that HXguy's "guy" came with good references in the beginning, if he wasn't involved - there's a good chance his house may have burned to the ground due to the installer's incompetence.

Another thing to keep in mind (that I've learned from hanging out on this site) is chasing the cheapest deal at the expense of quality and / or a fly-by-night installer. If a quote seems too good to be true; it probably is. Where I live (Edmonton, Canada), we don't have any subsidies so shopping around is a necessity. PV prices are roughly double than that in the US, so for those reasons; if I wanted to keep my ROI reasonably short I needed to find low cost panels. I picked up 9.45kW of used SunPower panels at under $0.45 per watt I also found an installer that is as excited as I am in having my project turn out as best as possible. His firm is relatively new but he's an engineer and has a master electrician on staff. My project is his largest so far, and he'll be using it as his reference installation to show other customers. In the last two months, he's answered at least 50 emails from me and has provided several possible PV designs free of charge.

Good luck!

Yes that is interesting that he had to do a lot of DIY even though he planned not to. And he didn't seem to have any trouble getting the inspections done without the installer present. However the installer did at least get all the permits for him.