What Surprises did you have?

[Murby]

For those of you who installed your own system, what surprises did you have? Unexpected costs? Did you need anything you didn't count on?

[organic farmer]

Our first solar panel mounting system was destroyed by hurricane Sandy. That required a re-design and was re-built a year later.

[SunEagle]

Our first solar panel mounting system was destroyed by hurricane Sandy. That required a re-design and was re-built a year later.

Damn. Sorry for your loss.

Was the damage from the wind ripping up the panels or wind blown debris hitting the panels?

[bcroe]

For those of you who installed your own system, what surprises did you have? Unexpected
costs? Did you need anything you didn't count on?

The biggest surprise was that the PoCo didn't bother to order and install a net KWH meter until 12 weeks
after I had paid them for it. There is really no reason not to do it immediately, even before the solar array is running.

The next surprise was just how much output was totally a function of weather. NO MENTION WAS MADE of the effects
of clouds or snow before the contract was signed. Or of any way to moderate them.

Probably the last major thing was how the PoCo could shut your investment down just by "allowing" the line voltage to
be too high. All the above have been dealt with, at some cost. Bruce Roe

[tyab]

For me (ground based system) during construction I ran into the follow issues that I never counted on. All were related to being a remote ground based install - none of them would have occurred on a roof system. Some of them were due to me sticking with a microinverter design instead of long DC run design (see note about buying stuff too early)

• Friend helping with excavation is a Cal-Fire dozer full time and basically could not help during the summer months due to all the fire we had in CA. Lost over a month of time.
• Rocks - we hit rock shelves and had the choice of calling in a guy to blast or move one of the mounts. Moving that forced a 2nd mount to move (too close, shading issues). Fortunately this was just when drilling holes so all we lost was the time to layout again in new location. But this caused far more digging into the hillside than we expected and thus later added to the retaining wall cost.
• Standard type of auger based trenching is not viable in my area, so trenches were dug with big equipment and were 3' wide. Heck there were sections that were 6' wide due to digging around large boulders so they could be rolled out. This massively increased the amount of sand to protect the electrical conduit - added five 32 tons loads I was not counting on.
• Rock shelve when digging trenches. Had to fill in about 100' and redig a different line to avoid a rock shelve.
• Trenches we had for LPE ground ring ran into large underground tree roots. Those had to be cleared by hand with hammer drill/chainsaw. Ran into rock shelve on side, just 12" underground. Used hammer drill to dig into downslope of that shelve to get deeper. Crazy number of hours doing that by hand. Ran into access issues for equipment on some trench locations and thus had to dig small sections by hand but that is a nightmare in these soil conditions. All total - about 60 hours. Lost most of August to those clearing issues. On the good side - helped me lose weight doing all that work.
• Due to another rock shelve could not have direct run from solar area subpanel to two of the mounts so we did a loop around the back. Added almost 100' of run for each string, and conduit and trench. All total added over 5000' of #6 wire that I did not count on. My other option was to use local subpanels on each mount to avoid the string runs. Net costs were a wash and I did not want to file another permit addendum so I just stuck with the original plan and long wire runs.
• Digging a trench across the driveway. I thought I could dig that by hand with hammer drill and lots of 18 year old labor. Nope - huge rocks. Had to use the big equipment and another 3ft wide trench. Still have not repaired that driveway yet - that will not be cheap.
• Unable to get concrete to site. Did not have timely access to friend with bobcat to move raw materials. Ended up just moving a ton of 60 lb bags manually - over 650 of them 12 at a time in a trailer pulled by a quad. Another good way to get back in shape. Took far more time than I thought.
• Everything took longer than I thought. Everything. Finally I realized that if I just 4x the time I thought something would take - I was getting close to reality. DYI when you have a full time job and thus you only have weekends, mornings, evenings, late nights - just getting going and shutting down in small work increments wastes a big chunk of your time.
• Reading the NEC carefully and following NEC code forums like the ones on mikeholts consumed many evenings - but I wanted to everything to pass first time and I know I did more than code required. Did make inspections short and easy however.
• Some of the tools needed was I not counting on. But I did try and save costs on them - lots of WWW searching and finding stuff on EBay.
• Weather. Project took us into rain season and we had a normal non-drought season. Really slowed stuff down. Massive mud from rain PITA to work in.
• Erosion control was far more extensive than I thought and was not in my original budget. But we figured that out early enough to make sure funds were available for it.
• Buying stuff too early. Don't buy stuff until you have a near timeline that purchase and delivery does not impact.
• Enphase does not like long distances from their reporting module to the microinverters. It works - barely. Have not resolved this issue yet but think I can do it over February. Was not planning on this extra work and expense at all.

Nothing about the actual hookup, permitting, and general electrical wiring was unexpected - no surprises there in my case.
Overall I would caution anyone doing a ground system where access is difficult - time and costs just explode on you.

PG&E in our region was amazingly easy to work with - super fast once final inspection passed. I was very surprised how easy the PG&E process was. System has been running close to a month now - no issues with PG&E or with grid tie with them.

No issues with neighbors due to system being remote and unable to impact them with glare or view or anything like that. One of the advantages of ground systems.

[foo1bar]

Definitely took more time to do the install than I was planning on.

I didn't have a good plan for joining PV wire to THWN.

Had to buy bolts, washers and nuts for fasteneing optimizers to rails.
(Not sure that was really a surprise - but was something that might not be in your plans.)


There were some tools I bought:
* MC4 crimper
* conduit bender
* clamps


And I would plan on spending a lot of time looking at what is necessary to do an install.
*grouding requirements
* wire size requirements
* how to get wires from the roof down to the inverter
* other things I dont' remember.

[bcroe]

For me (ground based system) during construction I ran into the follow issues that I never counted on. All were related to being a remote ground based install - none of them would have occurred on a roof system. Some of them were due to me sticking with a microinverter design instead of long DC run design (see note about buying stuff too early)

Thanks for taking the time to detail that out. Bruce Roe

[J.P.M.]

Murby: I've seen a lot of posts from you but unless I've missed it, I've seen nothing from you with any mention of your proposed array orientation, possible shading or what you expect an array to produce on an annual basis. What's your zip ?

[emartin00]

Our only problem was the arguing with the POCO. My dad had originally called, and they told him a 200A upgrade was free (the overhead wires). We did all the work, and then we he called to have the service upgrade, they told him he had to pay because it was for a solar install. After a little arguing, they did come do it for free. Finally got the new net meter installed a couple weeks ago.

[Murby]

Our first solar panel mounting system was destroyed by hurricane Sandy. That required a re-design and was re-built a year later.

I was going to hit the "like" button but it just didn't seem appropriate to like a post about your loss. That was very unfortunate. Did insurance cover it?

[Murby]

The biggest surprise was that the PoCo didn't bother to order and install a net KWH meter until 12 weeks
after I had paid them for it. There is really no reason not to do it immediately, even before the solar array is running.

The next surprise was just how much output was totally a function of weather. NO MENTION WAS MADE of the effects
of clouds or snow before the contract was signed. Or of any way to moderate them.

Probably the last major thing was how the PoCo could shut your investment down just by "allowing" the line voltage to
be too high. All the above have been dealt with, at some cost. Bruce Roe

Yup.. I understand the whole cloud problem.. Personally, I think they should put a daytime ban on any cloud formation over solar arrays.. pass a law and tell mother nature to get in line!

Interesting comment on your utility provider "allowing" line voltage to be too high.. Can you elaborate on that? I'm guessing this has something to do with inverter specifications?

[Murby]

For me (ground based system) during construction I ran into the follow issues that I never counted on. All were related to being a remote ground based install - none of them would have occurred on a roof system. Some of them were due to me sticking with a microinverter design instead of long DC run design (see note about buying stuff too early)

• Friend helping with excavation is a Cal-Fire dozer full time and basically could not help during the summer months due to all the fire we had in CA. Lost over a month of time.
• Rocks - we hit rock shelves and had the choice of calling in a guy to blast or move one of the mounts. Moving that forced a 2nd mount to move (too close, shading issues). Fortunately this was just when drilling holes so all we lost was the time to layout again in new location. But this caused far more digging into the hillside than we expected and thus later added to the retaining wall cost.
• Standard type of auger based trenching is not viable in my area, so trenches were dug with big equipment and were 3' wide. Heck there were sections that were 6' wide due to digging around large boulders so they could be rolled out. This massively increased the amount of sand to protect the electrical conduit - added five 32 tons loads I was not counting on.
• Rock shelve when digging trenches. Had to fill in about 100' and redig a different line to avoid a rock shelve.
• Trenches we had for LPE ground ring ran into large underground tree roots. Those had to be cleared by hand with hammer drill/chainsaw. Ran into rock shelve on side, just 12" underground. Used hammer drill to dig into downslope of that shelve to get deeper. Crazy number of hours doing that by hand. Ran into access issues for equipment on some trench locations and thus had to dig small sections by hand but that is a nightmare in these soil conditions. All total - about 60 hours. Lost most of August to those clearing issues. On the good side - helped me lose weight doing all that work.
• Due to another rock shelve could not have direct run from solar area subpanel to two of the mounts so we did a loop around the back. Added almost 100' of run for each string, and conduit and trench. All total added over 5000' of #6 wire that I did not count on. My other option was to use local subpanels on each mount to avoid the string runs. Net costs were a wash and I did not want to file another permit addendum so I just stuck with the original plan and long wire runs.
• Digging a trench across the driveway. I thought I could dig that by hand with hammer drill and lots of 18 year old labor. Nope - huge rocks. Had to use the big equipment and another 3ft wide trench. Still have not repaired that driveway yet - that will not be cheap.
• Unable to get concrete to site. Did not have timely access to friend with bobcat to move raw materials. Ended up just moving a ton of 60 lb bags manually - over 650 of them 12 at a time in a trailer pulled by a quad. Another good way to get back in shape. Took far more time than I thought.
• Everything took longer than I thought. Everything. Finally I realized that if I just 4x the time I thought something would take - I was getting close to reality. DYI when you have a full time job and thus you only have weekends, mornings, evenings, late nights - just getting going and shutting down in small work increments wastes a big chunk of your time.
• Reading the NEC carefully and following NEC code forums like the ones on mikeholts consumed many evenings - but I wanted to everything to pass first time and I know I did more than code required. Did make inspections short and easy however.
• Some of the tools needed was I not counting on. But I did try and save costs on them - lots of WWW searching and finding stuff on EBay.
• Weather. Project took us into rain season and we had a normal non-drought season. Really slowed stuff down. Massive mud from rain PITA to work in.
• Erosion control was far more extensive than I thought and was not in my original budget. But we figured that out early enough to make sure funds were available for it.
• Buying stuff too early. Don't buy stuff until you have a near timeline that purchase and delivery does not impact.
• Enphase does not like long distances from their reporting module to the microinverters. It works - barely. Have not resolved this issue yet but think I can do it over February. Was not planning on this extra work and expense at all.

Nothing about the actual hookup, permitting, and general electrical wiring was unexpected - no surprises there in my case.
Overall I would caution anyone doing a ground system where access is difficult - time and costs just explode on you.

PG&E in our region was amazingly easy to work with - super fast once final inspection passed. I was very surprised how easy the PG&E process was. System has been running close to a month now - no issues with PG&E or with grid tie with them.

No issues with neighbors due to system being remote and unable to impact them with glare or view or anything like that. One of the advantages of ground systems.

That was awesome! Thank you so much for taking the time to post all of that. Seems like most of your issues were related to the geology of your location and your ability to get some extra muscle on the job.
Fortunately for me, you'd be hard pressed to find better soil than I have. The top two or three feet here is all sandy loam topsoil, then it turns into hard packed sand.. I dug a post hole almost 60 inches down a few years back and finally hit a sandy kind of clay at the bottom. We have do have the occasional rock but its not a problem.

[bcroe]

Yup.. I understand the whole cloud problem

Interesting comment on your utility provider "allowing" line voltage to be too high.. Can you elaborate on that? I'm guessing this has something to do with inverter specifications?

I have managed to double output under clouds here; not full power, but at least the plant always is doing something. We
had a brief outage one day, and when power was restored line had risen from 120V (high) to 127V (out of limits, 254V
line to line). This goes even higher when the inverters are pushing power back along my own long run, so just when the
inverters should be delivering maximum power, they are constantly tripping off on "high line". A call to the PoCo didn't
get any results until finally after summer (best energy) was long over. The installer didn't seem to think it important (!?),
though I had requested allowance for high line at installation. But fortunately I was taking careful notes over his shoulder
when the inverters were configured, and observed they could be operated on 277V systems. No problems since then.
Bruce Roe

[sdold]

Our only problem was the arguing with the POCO. My dad had originally called, and they told him a 200A upgrade was free (the overhead wires). We did all the work, and then we he called to have the service upgrade, they told him he had to pay because it was for a solar install. After a little arguing, they did come do it for free. Finally got the new net meter installed a couple weeks ago.

It's funny how something that reduces the load current in the wires requires an upsize to the current-carrying capability of that wire.

[Murby]

Murby: I've seen a lot of posts from you but unless I've missed it, I've seen nothing from you with any mention of your proposed array orientation, possible shading or what you expect an array to produce on an annual basis. What's your zip ?

I have one Douglas Fir pine tree that I might have to take down if (big if) it causes any significant shading during sunrise. I don't think it will be a problem however because any shading it creates seems like it will be in the middle of summer and only for an hour during sunrise.

I'm in Michigan.. Current plan is a 6.9 KW system on the ground in the back yard. Four rows high by five columns long using Solarworld SW345 panels with 72 cells and a SunnyBoy 6KW inverter and IronRidge mounting hardware package which uses 3 inch galvanized pipe in concrete. The only change I think I'm going to make is to elevate the concrete forms to lift the entire array up about 3 feet so I can drive the zero-turn mower under it.

Tilt angle to be 33 degrees.
I used this link from NREL http://pvwatts.nrel.gov/ to determine that my location will produce about 8600 kWr per year under the specs listed below. I'm actually planning on 8000 kWr/year because my house is going to shade the panels during the last hour of sunset. I'm still calculating that as I type this.. Have to watch the sun cast shadows this evening and then calculate were it will be for each month.

Solar panels in Michigan don't do much during the middle of winter via the NREL figures.. So far, my system cost is $8100 (including ship) for the hardware from Renvu and I should be able to chew them down a bit but not counting on it..
Additional costs:
$948 (150ft x $6.32/ft) more to purchase 3 inch galvanized pipe for the racking hardware.. (IronRidge from renvu)
$350 for direct burial wire to connect the home to the array. I know this seems like a lot of money for just 150 or so feet of wire, but I'm going way over size so that in the future, I can hook up service to a pole barn on the other side of the array.. This requires a 100 amp service and a 3 conductor cable +Ground conductor..
$100 to rent trencher for a day
$300 for concrete for the pillars. (I have lots of plywood and 2x4's laying around to make forms)
$40 Junction box and $40 for a 3 pole L-N-L distribution block to tie the inverter cables to the house cables and then allow for the later installation of pole barn feeder wires. (I don't think the inverter connection can handle the large cable size)

Worse case scenario, I end up around $10,000 and will get back $3,000 of that from Uncle Sam.. My wife took all our electric bills for the past five years, complete with the kWr used each month and what we paid, and put it all into a spreadsheet. We use about 8000 kWh per year with most of that being used in the summer when I'm doing a lot of welding and running the air compressor frequently.

And a bit of a Joke:
My wife was reading all about the 30% rebate (tax credit) from the federal government. The language states that all labor, equipment and materials are covered for the installation of the solar system. There are certain specifications within building and electrical codes that specify minimum requirements but almost none that specify maximum requirements.

So what if I decide that the support system for my 6.9KW solar array needs to be a 40 x 60 pole barn??? Will Uncle Sam give me a 30% tax credit on the pole barn too?
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