diy solar systems which are good and which to stay away from

[gte]

I appreciate the advice sensij, thank you.

Humbly I would like to say that although I'm not an electrician by trade, I have taken the permit for homeowners in my county, passed the test and trenched/wired up my shed/sub panel and my pool. I also designed and built myself, my 3k square foot detached garage, trenched 250 feet to it and wired it up completely including its own 2 breaker panels (100amp and 175amp). I already have 400amp service to my house as well. I'm also very well versed with DC and AC theory and application in general.

All this is not me bragging or me saying that I know much about solar, because I do not know much about solar. I do however feel confident that I have the life experience to be able to do this project after I have taken the time to properly educate myself. I am considering this project for both reasons, the satisfaction of taking it on and completing it and to save money in the long run as well as add value to my home. I may also re-roof my roof so that I can take advantage of that federal tax credit with that.

If I have come across as expecting a boxed solution and 24/7 help line, I apologize for that misconception because I do not expect that at all. I did however want to make sure that my learning cornerstone was correct and solid, so that I did not start off on the wrong foot.

I did get one proposal from Solar City, I thought it to be high at 80k before rebates.

@GTE

You might find that a minimum budget for your DIY solar project is to get a competitive quote from a reputable installer and subtract 30%. This will get you in the ballpark a lot faster than trying to build the bill of materials for your specific installation without prior knowledge of what is required. The price you find published online from "wholesale" suppliers is unlikely to be much less than the price your installer will offer for the same equipment from their distribution network (if at all), even after the installer's markup is included.

Are you pursuing DIY because you have some spare time and want the challenge / pride of installing it yourself? If you are just doing it to save money, I think you may be underestimating the value of the knowledge and experience that a professional will bring to your job.

A good place to start to get a handle on the knowledge involved is to review the applicable codes to a solar installation. The 2005 NEC code relating to PV systems is shared by the administrators of this forum. This may or may not be the code your municipality has adopted, although it is a great example of the level of detail that is required to install the system safely. You will also need to understand how your local PV code interacts with the code of the existing electrical system, since the two do not exist in isolation.

There are a few other cost risks that exist in DIY that are covered in a professionally installed system cost:
1) The cost of improperly assembling the mounting system, and causing damage to your roof.
2) The costs of iterative submittals to your permitting office until all of the details are just right.
3) The costs of having to re-install the wiring because some part did not pass inspection by the AHJ. If you had cut components to a specific length, you would probably need to replace them.
4) If you intend to take advantage of net metering, the costs of hiring an licensed electrician to do the final hookup to your panel. Some utilities will not approve an application unless a licensed contractor is involved.
5) For a system of your size, a panel upgrade is likely, and is not cheap. That is not DIY, period.

There are many, many more risks and potential costs involved in the DIY approach. Solar installations are not "insert slot A into hole B" like kitchen cabinets, for instance. They are not even like adding a new breaker to your panel to run a circuit to your garage to operate the mill you picked up cheap, which although requiring a permit in most jurisdictions, requires much less knowledge and experience to do safely.

If you still intend to DIY... if you go slowly, and ask very specific questions relating to the problems you encounter, you may find that there are some very skilled members of this forum that will be able to help you. If you come in expecting to be handed a BOM, a set of instructions, and a 24/7 help line, you will disappointed. There might still be value in getting proposals from professional installers, since they will have tools to help determine what size the system should be to meet your needs, and ideally, be able to discuss with you the potential costs and benefits of sizing larger or smaller than that.

[sensij]

If you are dealing with installers with "large" overhead/profit margins you are going the wrong places. Typically in most areas solar PV is very competitive.

@foo1bar
Based on the content of your posts, you seem to have much of the knowledge that I assign value to. I would have guessed you are a professional, and apparently you are not. I would also guess that your knowledge has not been come by quickly or easily. Someone asking questions that do not exhibit the same awareness of the work to be done has a long road ahead, which you have already traveled. Maybe it was easy for you, but I do not think that will be true in general. I did not mean to imply that DIY could never be cost-effective. I only meant that there is a lot that can go wrong that can jeopardize the budget, and a lot to learn on the first time through. I didn't even address the "dumb stuff", like how to get the panels on the roof without breaking them, or ways to make sure you don't accidentally fry electronics you care about. Watch enough home renovation shows and you see that absolutely nothing can be assumed. People who do it for a living learn these things. People like you figure it out, and more power to you. People like me try to do a lot, but eventually draw a line and say, I'm better off hiring some help.

I am not a professional, but through happenstance came into possession of an estimating spreadsheet used by one. Yes, I'd love to save some money, but after looking though the numbers, I don't think what I could save would justify the amount of work it would take to learn how to do it right, and cover the risks of doing it wrong. Others can certainly disagree, and my conclusions might not apply to a system of a different design.

Another point to consider is that relative to the payback of going solar, the costs associated with hiring an installer (over doing it DIY) really shouldn't make or break the decision. If it does, I would suggest that too much confidence is being placed in the assumptions used to perform the analysis.

[foo1bar]

If you are dealing with installers with "large" overhead/profit margins you are going the wrong places. Typically in most areas solar PV is very competitive.

Doesn't seem that they're that competitive with each other around here.

On a 5kW or 8kW system, DIY comes out to $2.00-$2.20/W (nameplate)
The people that I have talked to it's $3.25 to $3.50+/W.

If someone has an installer in the bay area that's able to get down to below $3.00/W, I'd be very interested in talking to them.
Or if there was someone who does it on time & materials.

I've also been helping with evaluating bids for a ~50kW setup (yes, 50,000W - ~200 panels).
The 3 proposals there were for a PPA purchase, and none of them were good enough to pursue.

[foo1bar]

@foo1bar
Someone asking questions that do not exhibit the same awareness of the work to be done has a long road ahead, which you have already traveled.

I actually haven't even really started my install yet.
The main panel and meter upgrade is done (125A -> 200A) - but there's a lot to do yet.

[sensij]

I did get one proposal from Solar City, I thought it to be high at 80k before rebates.

@GTE
I'm sorry to have underestimated your experience and ability, I do not think it has been clear from the content of your posts so far. Anyone learning about solar has a hill to climb, and the forum is interesting in that it creates a record of that learning process. In this form of communication, it is easy to pigeonhole certain users and fail to recognize growth that occurs over time.

80k does seem high, although your system is beyond the scale of what I've been most interested in. You might really want to find a local installer and see what they say, especially if you can find someone in your area to refer you. The savings for DIY may be substantial enough you to pursue, but I'll stand by my advice more often than not.

[sensij]

I actually haven't even really started my install yet.
The main panel and meter upgrade is done (125A -> 200A) - but there's a lot to do yet.

I believe that by the time you get to the install, most of the road is traveled. Learning and planning are way more work than turning screws or plugging in connectors.

[russ]

Doesn't seem that they're that competitive with each other around here.

On a 5kW or 8kW system, DIY comes out to $2.00-$2.20/W (nameplate)
The people that I have talked to it's $3.25 to $3.50+/W.

If someone has an installer in the bay area that's able to get down to below $3.00/W, I'd be very interested in talking to them.
Or if there was someone who does it on time & materials.

I've also been helping with evaluating bids for a ~50kW setup (yes, 50,000W - ~200 panels).
The 3 proposals there were for a PPA purchase, and none of them were good enough to pursue.

Evaluating bids - meaningless

You have a lack of understanding of what goes into it or value your time at zero.

[gte]

No need to apologize ... no one hear knows me personally so there is no way to know ahead of time. You all are just people helping solar newbs such as myself, so I appreciate that.

I did not want to act like a know it all so I may have sand bagged a little (albeit unintentionally) trying to make sure I did not come across that way?

I do realize that the more I learn about solar, the more I can speculate that I don't know about it. I've learned through life that usually with first time DIY projects, you waste because of the lack of previous experience ... I am hoping to be successful, not waste too much time or money and still come out financially ahead. The second and third time are always cheaper and more efficient, but my family may be the benefit of the second and third time if this turns out well. I was really wanting to see a component list because I have never seen a complete solar system up close to make a mental list about it, and then start working through how it interacts in my head. I like to ponder projects in my head in my free time before I do them.

One of the reasons my electric bill is high is because the garage has a heat pump installed in it, I have a lift, a compressor and a tig welder ... most of the use probably being the heat pump. I don't need 70F year round, but I don't want sweating to death or freezing to death either. It sure would be awesome if I could heat and cool the garage with the Sun.

@GTE
I'm sorry to have underestimated your experience and ability, I do not think it has been clear from the content of your posts so far. Anyone learning about solar has a hill to climb, and the forum is interesting in that it creates a record of that learning process. In this form of communication, it is easy to pigeonhole certain users and fail to recognize growth that occurs over time.

80k does seem high, although your system is beyond the scale of what I've been most interested in. You might really want to find a local installer and see what they say, especially if you can find someone in your area to refer you. The savings for DIY may be substantial enough you to pursue, but I'll stand by my advice more often than not.

[foo1bar]

You have a lack of understanding of what goes into it or value your time at zero.

So educate me. What goes into it that I'm missing?
I see these 5-8kW systems go up in 1-2 days with a crew of 2 or 3.

The amount of time I will spend on it (beyond time I'd use if only hiring an installer) I am estimating to be about 8 days.
Even if I said $1K/day, I still am better off with DIY.
(And I'm not using $1k/day since this is fun for me)

[sdold]

So educate me. What goes into it that I'm missing?
I see these 5-8kW systems go up in 1-2 days with a crew of 2 or 3.

Not sure if this is what he's referring to, but I did a DIY system and more time was spent planning and engineering the system than the actual install, which itself was a long time (I worked alone). There are wind and structural loads to work out, the electrical design, and all of it needs to be put into drawings for the AHJ. I spent many hours doing this before I even ordered my first part. Now the installer knows how to do it and will take much less time, and will probably use a "cookie cutter" approach that borrows from previous installs, but it still needs to be taylored to your job.

Then there is all of his expenses besides the labor, like insurance, utilities, rent, phone bills, licenses, the secretary, the salesman, the trucks, tools, and on and on. I've never gotten the feeling that the local installers are getting rich from solar. If anything, doing my own install gave me more respect for the fact that they are able to make a living doing this.

I did it for "fun" too, so I wouldn't want to talk anyone out of it, I just think it's easy to underestimate the amount of work involved in the planning and permit stage.

[russ]

So educate me. What goes into it that I'm missing?
I see these 5-8kW systems go up in 1-2 days with a crew of 2 or 3.

The amount of time I will spend on it (beyond time I'd use if only hiring an installer) I am estimating to be about 8 days.
Even if I said $1K/day, I still am better off with DIY.
(And I'm not using $1k/day since this is fun for me)

please do so - just don't whine when you find all sorts of things you haven't considered.

[J.P.M.]

So educate me. What goes into it that I'm missing?
I see these 5-8kW systems go up in 1-2 days with a crew of 2 or 3.

The amount of time I will spend on it (beyond time I'd use if only hiring an installer) I am estimating to be about 8 days.
Even if I said $1K/day, I still am better off with DIY.
(And I'm not using $1k/day since this is fun for me)

It's a free country. Pay your money, take your choice. Enjoy. I for one would like to know how it works out for you - the good, the bad & the ugly, if you feel up to sharing when done.

Good luck.

[PVAndy]

Pardon me for jumping in here. Much of what I've read here is good information. I am not a novice. I head the engineering department of a fairly decent size design / install company. I've been involved from concept to installation for several thousand systems.

However that being said I finally got around to installing a 15 kW STC DC system at my own house. I certainly contemplated doing the panel install myself, but opted to have 3 of our best installers do it on weekends. It took 3 very seasoned installers 2 days to install 60 panels. I would still be at it. I'm doing the electrical myself and have been at it for several weekends,

If you not familiar with the process at least here in Conn / Mass / New York systems over 10 kW AC go through a different review process to be approved for interconnect. I end up doing reactive power diagrams to get many of these systems approved to energize to guarantee grid stability.

Existing roof structure, live load, dead load, snow load, and wind uplift all require a Professional Engineers calculation and stamped drawings and calculations to get building gpermits. The utilities require Protection and Control and Witness Test Procedures. Again possible for a DIY to do, but probably tough the first time.

In most areas the Utility requires an AC Disconnect in close proximity to the Utility Meter. Also for those of you in states where NEC 2014 has been adopted don't forget that you need to comply with "Rapid Shutdown" and Fire Code requirements relative to panel location and setbacks. Another tidbit that I believe is in effect in CA is that the racking and panel together must be certified as a unit not to degrade the fire class rating of the existing roof (A,B or C) This can be a big deal to accomplish

Just wanted to give you a couple of points to consider- they may not all be applicable to your system. Also remember what you can interconnect may be limited by existing utility transformer and line loads.

Andy

NABCEP Certified Installation Professional
PV Design Engineer

[foo1bar]

Pardon me for jumping in here. Much of what I've read here is good information. I am not a novice. I head the engineering department of a fairly decent size design / install company. I've been involved from concept to installation for several thousand systems.

However that being said I finally got around to installing a 15 kW STC DC system at my own house. I certainly contemplated doing the panel install myself, but opted to have 3 of our best installers do it on weekends. It took 3 very seasoned installers 2 days to install 60 panels. I would still be at it. I'm doing the electrical myself and have been at it for several weekends,

If you not familiar with the process at least here in Conn / Mass / New York systems over 10 kW AC go through a different review process to be approved for interconnect. I end up doing reactive power diagrams to get many of these systems approved to energize to guarantee grid stability.

Existing roof structure, live load, dead load, snow load, and wind uplift all require a Professional Engineers calculation and stamped drawings and calculations to get building gpermits. The utilities require Protection and Control and Witness Test Procedures. Again possible for a DIY to do, but probably tough the first time.

In most areas the Utility requires an AC Disconnect in close proximity to the Utility Meter. Also for those of you in states where NEC 2014 has been adopted don't forget that you need to comply with "Rapid Shutdown" and Fire Code requirements relative to panel location and setbacks. Another tidbit that I believe is in effect in CA is that the racking and panel together must be certified as a unit not to degrade the fire class rating of the existing roof (A,B or C) This can be a big deal to accomplish

Just wanted to give you a couple of points to consider- they may not all be applicable to your system. Also remember what you can interconnect may be limited by existing utility transformer and line loads.

Andy

NABCEP Certified Installation Professional
PV Design Engineer

Thanks Andy - really appreciate you taking time to point out some of the things that may be areas that can trip up a DIY installation.


One thing in there I didn't recognize: "utilities require Protection and Control and Witness Test Procedures."
That's not phrasing I've seen before (even after looking at my utility's interconnect requirements)
Can you explain what that means? Or how it's done by installers? (ex. is it just tripping the breaker and seeing that the system shuts down? Or is this something just for >10kW systems which would explain why I haven't seen it.)

[wirebender06]

Great info

thanks for your input Andy, its very useful!