# Ground-mount 9Kw solar install beginning today



## 7acres (Dec 14, 2016)

Hi all,
  Today's the day. They dropped off a Bobcat with auger attachment an hour ago. Monday they dropped off the racking and inverters. They're aiming to have the install completed by the end of the week.

A rundown of the grid-tie install:
* 8.96Kw from 32 Canadian Solar panels
* Schletter ground mount racking hardware
* 2X SMA SunnyBoy (SB 5.0-US) 5000W Inverters
* Oversized wire, conduit and combiner creating potential to add another 5kw in the future.
* Anti-theft fasteners

Here's today's progress from a half day of work:


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## semipro (Dec 14, 2016)

Congratulations.  Thanks for posting.  Until we get our I'm enjoying installs like this vicariously.


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## jebatty (Dec 15, 2016)

Congrats, also. Except for string inverters (mine are micros), your system is a lot like mine, now in use for just over 3 years. Over-sizing the wiring is an excellent choice. I did the same, started with a 6.9kw system, then expanded to 12.4kw using wiring already installed. Sunny day yesterday after nearly a month of heavy cloud cover, typical for Nov-Dec, and 31kwh produced,


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## mol1jb (Dec 15, 2016)

jebatty said:


> Congrats, also. Except for string inverters (mine are micros), your system is a lot like mine, now in use for just over 3 years. Over-sizing the wiring is an excellent choice. I did the same, started with a 6.9kw system, then expanded to 12.4kw using wiring already installed. Sunny day yesterday after nearly a month of heavy cloud cover, typical for Nov-Dec, and 31kwh produced,



31 kwh in a day?


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## jebatty (Dec 15, 2016)

Yes, that was 31 kwh on Dec 14, very close to the shortest day of the year, and the sun only rising to about 19* above the horizon. Today was sunny also, and 32 kwh. My all-time high daily production so far has been 89kwh, that occurring on April 22, 2015. Total annual production is running right around 15-16 Mwh


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## 7acres (Dec 15, 2016)

Today the crew struggled to get the 24" auger to go any deeper than about two feet deep before hitting granite bedrock. The auger Sunbelt rented them wasn't sharp or something. I dug 35 holes right into the same granite with a bobcat/auger setup just like they had 6 years ago when the orchard went in. They will be bringing a jackhammer tomorrow. 

After trying all 6 holes and getting the same result they changed tack and continued with the AC-side of the install.


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## jebatty (Dec 15, 2016)

My Schletter mounts were installed in a meadow wetland, and core drills to 8' before gravel/sand was reached to provide a firm foundation for the concrete footings.


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## mol1jb (Dec 15, 2016)

That is some cool tracking software. Are you still grid tied with your setup?


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## jebatty (Dec 16, 2016)

Still grid tied - yes. When economical kWh energy storage becomes available, I seriously would consider going off grid. Below is the graph for the 89 kWh day.


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## mol1jb (Dec 16, 2016)

If you don't mind me asking what kind of cost is a set up like your run? I would love to get a solar system for our property but I don't think I can afford it currently.


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## jebatty (Dec 17, 2016)

Cost is dependent on area labor rates, type of install, choice of components, permits and inspections required, etc. In my area a high quality ground mount system on a turn-key basis currently can be acquired for about $2.50 to $3/watt. So a 5,000 watt DC system would require a cash outlay of about $12,500 - $15,000 before the federal tax credit and other available incentives, which can be very substantial depending on your state and utility. 

If your state has net metering and/or certain kinds of incentives, you especially have to look at a PV system not as a "cost" but as an investment, because it will produce a monetary value return as soon as it is operable which can recover your cash outlay quite quickly and then continue to add to your bottom line. Economic payback time therefore is variable, but investment return starts from day one. Depending on the financial analysis, it may be wise to obtain a home equity loan or other loan to get the needed cash because the rate of return on the system easily can be greater than the interest rate on the loan.


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## peakbagger (Dec 17, 2016)

mol1jb said:


> If you don't mind me asking what kind of cost is a set up like your run? I would love to get a solar system for our property but I don't think I can afford it currently.



Interestingly, the OP actually wasn't thinking about solar when he made a post about energy use and we encouraged him to look at solar. It turns out that the incentives for solar in his state are incredible and its probably the best investment he can make (I sure hope so, as I don't want to have egg on my face). There is 30% federal incentive that everyone gets but every state and possibly utility has different incentives and regulations that may or may not encourage solar. I would suggest going to this website and see what incentives apply specifically to you http://www.dsireusa.org/. You need to review the incentives and see if there is "net metering" and if so what the details are, as differing net metering rules may change the size of your system. Keep in mind that if in doubt the best investment is to spend money not to need to use electric power, typically every dollar spent on energy efficiency has far better payback that putting in PV.

One big caution is that there is an entire industry that has sprung up that is really a tax dodge for big investors that is hidden by folks desire to be green. These are big national firms that push creative financing options that you want to steer clear of. Effectively the many variations boil down to they get a long term attachment on your property where they get the vast majority of the benefits while giving you a small benefit that you could come to regret if you ever want to sell the house. Ideally you only would want to install a solar system on a house that you plan to keep long term. You would want to buy the system outright after making sure you have taken advantage of every incentive and if need be take a short term home equity loan out to pay the balance.


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## mol1jb (Dec 17, 2016)

I appreciate all the info. It is definitely something I want to research more. I have only lived in our house one year but we hope to live here for atleast 15+ years. It is a large city lot, just over 1/2 acre. With regards to placement of roof vs ground mounted, is there a recommendation one way or the other? Both my roof (rear of house faces south) and yard have good south facing options.


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## peakbagger (Dec 17, 2016)

Roof mount is typically less expensive than ground mount as long as there is no shading, Vent pipes and chimneys can really impact production. Individual microinverters on each panel can help with the shading issue but increases the over all cost of the system. One thing to factor in is generally with roof mounts, its highly recommended that you replace the roof shingles before you install the panels so you can delay the inevitable of having to remove the panels to replace the shingles.


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## mol1jb (Dec 17, 2016)

peakbagger said:


> Roof mount is typically less expensive than ground mount as long as there is no shading, Vent pipes and chimneys can really impact production. Individual microinverters on each panel can help with the shading issue but increases the over all cost of the system. One thing to factor in is generally with roof mounts, its highly recommended that you replace the roof shingles before you install the panels so you can delay the inevitable of having to remove the panels to replace the shingles.



Thanks for the info. Makes sense with the roof replacement. My shingles have a few years left and we will be replacing with metal. Definitely interesting


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## 7acres (Dec 17, 2016)

Yeah, my install is roughly $35k. Then Federal will cover 30%, State 25% and the utility will cut me a check for $8,960 ($1 per watt). So after all the rebates, etc it will have cost us a net of about $8,500 for the install. It will pay for itself in under 5 years. Then it's just pure savings from that point on.


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## 7acres (Dec 17, 2016)

The crew returns Monday and will be here all week. Probably finishing it up by the end of the week. We can't wait to see it completed! 

I also can't wait to get my first electricity bill with the house on solar


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## mol1jb (Dec 17, 2016)

7acres said:


> Yeah, my install is roughly $35k. Then Federal will cover 30%, State 25% and the utility will cut me a check for $8,960 ($1 per watt). So after all the rebates, etc it will have cost us a net of about $8,500 for the install. It will pay for itself in under 5 years. Then it's just pure savings from that point on.



Wow that is a great price for install and even better return. Roughly how many kwh do you use per month?


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## 7acres (Dec 17, 2016)

From memory the range goes from 1000Kw/hrs in the Winter (wood stove/no heat pump at all) and 2400Kw/hrs in the Summer (Air Conditioning running full tilt). The average seems to be 1450Kw/hrs.


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## mol1jb (Dec 17, 2016)

7acres said:


> From memory the range goes from 1000Kw/hrs in the Winter (wood stove/no heat pump at all) and 2400Kw/hrs in the Summer (Air Conditioning running full tilt). The average seems to be 1450Kw/hrs.



Very cool. And how much is your setup estimated to produce per month?


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## 7acres (Dec 17, 2016)

Oh, how does the math work? 9 x Hours of Sun in the day. Then multiply that by 30 days. Then multiply that by the efficiency rating. Something like 87%.

It's a bell curve from January to December. The least power produced in Winter and the highest production in Summer. 

Somebody please correct me here. I'm sure my math is off somewhere.


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## peakbagger (Dec 17, 2016)

Easiest way to figure out performance is to look for PVWatts on the internet. Enter your location, array size,  the type of mount and panel angle plus its location relative to south and the project gives you a generally conservative monthly and yearly production number based on your local weather conditions. Works good except if the panels are covered with snow in the winter.

I have a total of 4.6 KW in three different types of array and generate more power than I use every year. I carried 2000 KWH into this winter which I use to run a mini split to heat my house when the temps are over 30 degrees.


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## Where2 (Dec 18, 2016)

The math is entirely complicated. When the sun first peeks over the horizon in the early morning, it is not nearly as intense as it is at mid-day because of all the air and particulates in the atmosphere. At mid-day, the sun is punching through the least amount of atmosphere and particulates to hit the panels, and the rays of the sun are hitting the panel (hopefully) fairly close to perpendicular.

Much like shining a flashlight perpendicular to a wall will produce a smaller, much more intense concentration of light than shining it up from the base of the wall where the light beam washes along much more wall area, yet produces less intense light, solar panels work much better with direct sunlight from overhead. Overcast days where there is lots of scattering of the sunlight, your production will be much lower than a cloudless clear day. With my system, I can tell you when a cloud passes over.

PVWatts 2 certainly gives a good measure of performance. You can also get a "ball park" for a given area by searching through maps like the one Enphase has that shows "public enphase PV system" production numbers. I watched the daily production numbers on an installation about a mile from my house for close to a year while I pieced together the parts to install my own array. I'm presently watching an enphase system 2,000 miles away from my array #1 (near our summer farm property) to get a feel for what the 4.6kW array I'm designing will produce in a vastly different climate from where array #1 is.


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## peakbagger (Dec 18, 2016)

Where2 said:


> The math is entirely complicated. When the sun first peeks over the horizon in the early morning, it is not nearly as intense as it is at mid-day because of all the air and particulates in the atmosphere. At mid-day, the sun is punching through the least amount of atmosphere and particulates to hit the panels, and the rays of the sun are hitting the panel (hopefully) fairly close to perpendicular.



For those in cold climates, the outdoor air temp also factors in, PV panels like cold temps (up north my panels will actually put out more watts than the panel rating on very cold days (-10 or below). Hot temps reduce the output per panel but usually the logner days in summer offset the reduced performance.  Snow on the ground also makes a difference as it will reflect more sun on the panels. Panel angles also factor in, my pole mount has an adjustable angle, I adjust mine 4 times a year to optimize the angle. Vermont has an odd incentive system that encourages the installation of solar arrays that "track" the sun. they adjust their sweep left to right and the angle up and down, these systems can put out 30% more power than a fixed array. The reason most folks don't use trackers is the initial cost is steep. Unless there are incentives to offset the initial cost its far better to install more panels as they are much cheaper. (they are pretty interesting to watch over the course of the day).


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## mol1jb (Dec 18, 2016)

peakbagger said:


> Interestingly, the OP actually wasn't thinking about solar when he made a post about energy use and we encouraged him to look at solar. It turns out that the incentives for solar in his state are incredible and its probably the best investment he can make (I sure hope so, as I don't want to have egg on my face). There is 30% federal incentive that everyone gets but every state and possibly utility has different incentives and regulations that may or may not encourage solar. I would suggest going to this website and see what incentives apply specifically to you http://www.dsireusa.org/. You need to review the incentives and see if there is "net metering" and if so what the details are, as differing net metering rules may change the size of your system. Keep in mind that if in doubt the best investment is to spend money not to need to use electric power, typically every dollar spent on energy efficiency has far better payback that putting in PV.
> 
> One big caution is that there is an entire industry that has sprung up that is really a tax dodge for big investors that is hidden by folks desire to be green. These are big national firms that push creative financing options that you want to steer clear of. Effectively the many variations boil down to they get a long term attachment on your property where they get the vast majority of the benefits while giving you a small benefit that you could come to regret if you ever want to sell the house. Ideally you only would want to install a solar system on a house that you plan to keep long term. You would want to buy the system outright after making sure you have taken advantage of every incentive and if need be take a short term home equity loan out to pay the balance.



Are you able to post the link to that thread? Id love to read through it.


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## Scotty2 (Dec 18, 2016)

You mentioned ... * 2X SMA SunnyBoy (SB 5.0-US) 5000W Inverters.
We have 5 of these in our 30kW system.
Ran 3 Inverters to one AC combiner panel, 2 to another. The reasoning was we'd never be able to afford the battery storage for 30kW production.
Our plan is for 2 Inverters to charge the (future) batteries... and the remaining 3 Inverters doing a redirect to something like a Talapia pond (warm water)...and powering the water pump to fill some large water tanks at the highest spot on the property.
An interesting note on the Sunny Boy Inverters. They have a 2kW internal Storage capacity (I think I have that right)...I've been told you can set them up to run the small pumps on your boiler/radiant system when the power is out and the so is the Sun.


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## peakbagger (Dec 19, 2016)

mol1jb said:


> Are you able to post the link to that thread? Id love to read through it.



https://www.hearth.com/talk/threads/any-mature-solution-for-solar-air-conditioning.155877/


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## peakbagger (Dec 19, 2016)

Scotty2 said:


> You mentioned ... * 2X SMA SunnyBoy (SB 5.0-US) 5000W Inverters.
> We have 5 of these in our 30kW system.
> An interesting note on the Sunny Boy Inverters. They have a 2kW internal Storage capacity (I think I have that right)...I've been told you can set them up to run the small pumps on your boiler/radiant system when the power is out and the so is the Sun.



Technically the SPS doesn't store power, what it does is puts out a limited amount of 120 VAC to a separately switched circuit as long as sun is shining. Its not backup power as its dependent on sunlight but could be used along with UPS and some switching circuitry for some backup power.

Its more of a marketing ploy than a substitute for good generator but a neat feature nevertheless.  Each circuit is rated at 1500 watts irrespective of the rating of the inverter.


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## woodgeek (Dec 19, 2016)

The output math is more complicated than the number of hours of daylight per day due to the output going like cos(theta) where theta is the angle the sun makes with the panel perpendicular (and which defines the bell curve of Jim's output plot).  It only makes rated output when theta = 0.  If the panel were rotating in empty space once per 24 hours it would yield just 6 hours times the nominal output per day, or a capacity factor of 0.25.  On a cloudless point on the earth, adjusting the tilt periodically, such a 0.25 CF would be 2200 hours * nominal power per year, 1 Watt of panel would make 2.2 kWh per year.  In practice, different locations in NA with a fixed panel have between 1000-2000 hours of solar resource per year, you can google solar resource maps for your location.


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## mol1jb (Dec 19, 2016)

Does anyone know the price difference in stall cost for ground vs roof mount in general? Im sure it depends on length of wire being run. I could do either at my house however the best ground mount spot on my lot is about 100ft from the house. In terms of adjustment, cleaning, snow removal, and maintenance the ground mount seems much easier to access


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## jebatty (Dec 19, 2016)

woodgeek said:


> It only makes rated output when theta = 0.


 How I wish. Throw into the mix ambient temperature, humidity, dust, haze, clouds and other atmospheric disturbances, panel soiling, electrical resistance between the panels and the panels to the measuring device, etc., and achieving rated output is a day to celebrate. Not perfect memory, but I think my 12.3kw system achieved rated output for a fairly short period (around solar noon) once, and the original 6.9kw system achieved, and even briefly exceeded rated output, only a small handful of times.

A few interesting websites:
insert your own address: http://suncalc.net/#/41.8781,-87.6298,10/2013.12.29/20:12
insert nearest location: http://solarelectricityhandbook.com/solar-irradiance.html
insert your own address: http://www.solartopo.com/solar-orbit.htm
insert location: http://pvwatts.nrel.gov/pvwatts.php


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## jebatty (Dec 19, 2016)

mol1jb said:


> the best ground mount spot on my lot is about 100ft from the house. In terms of adjustment, cleaning, snow removal, and maintenance the ground mount seems much easier to access


 My ground mount is 220 ft from the house. I have about a 1% loss of energy between the panels recorded total watts output and the watts measured at the house on a separate production meter. 

If you go underground, install the cable which can carry the maximum amperage you can backfeed to your panel, in the event the system you install is not the largest the code permits. That will allow future added panels, if you desire, without the need to add to or re-do the underground. Also consider adding an ethernet cable. Some systems can use that to provide lots of data to your computer. My system communicates either by wi-fi or ethernet, but at 220 ft the system is beyond reliable wi-fi range.


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## peakbagger (Dec 19, 2016)

mol1jb said:


> Does anyone know the price difference installed  cost for ground vs roof mount in general? Im sure it depends on length of wire being run. I could do either at my house however the best ground mount spot on my lot is about 100ft from the house. In terms of adjustment, cleaning, snow removal, and maintenance the ground mount seems much easier to access



Hard to do a rule of thumb as soil conditions can really screw up the cost. The solutions will vary with the soil type and owners preference. Some folks build frames out of pressure treated and then use commercial roof racking to tie the panels in. Others go with fully pre-engineered rack systems. Usually the actual foundations are designed and built for the local site. Most large solar installs I have seen in Mass are auger type feet.

One thing to consider with ground mount is access. Even though the code allows the use of mesh type screening system to be installed on the back of the panels to prevent untrained people from accessing the wiring, many inspectors seem to require a fencing to be installed around the panels to prevent access. Shading has to be taken in effect with a fence to ensure that the fence does not  cast a shadow on the panels in the winter.

The other thing to consider is ground mounts can be exposed to more abuse and potential theft. I believe the OP is using theft resistant hardware. Law mowers can throw rocks as ground mounts a lot easier than a roof mount and kids with baseballs also are more likely able to tag a ground mount. Both

The general rule of thumb I have seen to be taken with grain of salt is 25 to 30% added for ground mount plus trenching.  Of course the fed will pay 30% of the costs to install, so the actual increase is tempered a bit. I have heard of a few folks that used the solar install to deal with other long term issues like running power to a remote location by using the trenching I expect that's between them and their accountant on what they take for the solar credit.  

Most solar contractors can give tighter bid for a roof mount as that's their bread and butter. Ground mounts will have more contingency due to the unknowns like the OP just ran into.


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## mol1jb (Dec 19, 2016)

peakbagger said:


> Hard to do a rule of thumb as soil conditions can really screw up the cost. The solutions will vary with the soil type and owners preference. Some folks build frames out of pressure treated and then use commercial roof racking to tie the panels in. Others go with fully pre-engineered rack systems. Usually the actual foundations are designed and built for the local site. Most large solar installs I have seen in Mass are auger type feet.
> 
> One thing to consider with ground mount is access. Even though the code allows the use of mesh type screening system to be installed on the back of the panels to prevent untrained people from accessing the wiring, many inspectors seem to require a fencing to be installed around the panels to prevent access. Shading has to be taken in effect with a fence to ensure that the fence does not  cast a shadow on the panels in the winter.
> 
> ...



Thanks for all the info. I read for a roof install that one needs to check on weight limits of the roof. How common is it that a roof is unable to support a an average sized PV system?


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## peakbagger (Dec 19, 2016)

Depends on the local inspector, its pretty rare that its an issue other then having to write a check to PE to stamp a report.


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## jebatty (Dec 20, 2016)

OK, need to admit again, I am a solar PV addict. I have ground mount, and I can't stand snow or ice on my panels. I need to get snow off the panels as soon as possible. If I had roof mount, I might have avoided the addiction because I would have gotten used to seeing many days of no or little winter production due to snow covered panels. But with ground mount, I need to get it off, and a soft floor broom pulls of the snow and clears the panels easily. Takes about 15 minutes.

The difference between sunny day production with snow vs no snow in the heart of December is about 30kWh, valued at $3.50. For 15 minutes of effort, that's $14/hr of tax free electricity plus the value of fresh air and some exercise. Can't resist.


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## peakbagger (Dec 20, 2016)

My roof array is currently covered with 6" of frozen snow. Its going to take several days of sunny above freezing weather before I get any production from that array. To clean that one off requires a 30 foot extension ladder and snow rake. Luckily the OP is in South Carolina so I expect he doesn't have to worry about it.


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## 7acres (Dec 20, 2016)

Correct! I don't have to worry much about snow.

But we hit a bit of a glitch yesterday. We hit solid granite bedrock about 2' down. Apparently the Schletter system's structural needs require each pylon to be set in concrete 6' underground. The auger hit bedrock on all 6 holes. I know I have a lot of granite out here. But I put in an orchard with an auger 6 years ago and found the granite to be soft. Didn't have any issue with the Bobcat and 22" auger we used for that in the same surrounding area as the panels are slated to be installed in. But I can't argue. Here's one of the holes...





I saw the guys trying. They were manhandling that auger to get it to grab and break the granite. It only polished it up nice and flat!


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## 7acres (Dec 20, 2016)

The installer is looking into switching the racking system to a FlexRack product. From the short phone call I was just on it uses a ballast system that doesn't require 6' holes. I don't know much else at the moment. What do you guys think about FlexRack?


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## peakbagger (Dec 20, 2016)

Bummer! I am not familiar with the particular product but ballasted systems are used extensively on large roof top arrays. If the system is designed to your location conditions which are probably high winds it should be fine.

As a DIYer I would probably just make up some struts with plates on the bottom and then drill anchors into the rock if it was not fractured. Bolted into rock is about the best anchor system bar none.


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## Scotty2 (Dec 20, 2016)

jebatty said:


> My ground mount is 220 ft from the house. I have about a 1% loss of energy between the panels recorded total watts output and the watts measured at the house on a separate production meter.
> 
> If you go underground, install the cable which can carry the maximum amperage you can backfeed to your panel, in the event the system you install is not the largest the code permits. That will allow future added panels, if you desire, without the need to add to or re-do the underground. Also consider adding an ethernet cable. Some systems can use that to provide lots of data to your computer. My system communicates either by wi-fi or ethernet, but at 220 ft the system is beyond reliable wi-fi range.


Our ground mount is 450' from the Inverters and Panels. We did oversize the pipe...it was still a tough pull. We used a Simpson Capstan Rope Winch from Log Home Store https://www.loghomestore.com/c142-portable-winches.php
With all the effort to trench and bury we should have dropped a spare pipe (or 2) in the trench...e.g. future 110 power, phone, array add-on, you never know.


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## Scotty2 (Dec 20, 2016)

7acres said:


> Correct! I don't have to worry much about snow.
> 
> But we hit a bit of a glitch yesterday. We hit solid granite bedrock about 2' down. Apparently the Schletter system's structural needs require each pylon to be set in concrete 6' underground. The auger hit bedrock on all 6 holes. I know I have a lot of granite out here. But I put in an orchard with an auger 6 years ago and found the granite to be soft. Didn't have any issue with the Bobcat and 22" auger we used for that in the same surrounding area as the panels are slated to be installed in. But I can't argue. Here's one of the holes...
> 
> ...


Was this a hand held auger? or a Tractor/Bobcat mount?


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## 7acres (Dec 20, 2016)

Scotty2 said:


> Was this a hand held auger? or a Tractor/Bobcat mount?


Mounted to a Bobcat T190.


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## NateB (Dec 20, 2016)

peakbagger said:


> Bummer! I am not familiar with the particular product but ballasted systems are used extensively on large roof top arrays. If the system is designed to your location conditions which are probably high winds it should be fine.
> 
> As a DIYer I would probably just make up some struts with plates on the bottom and then drill anchors into the rock if it was not fractured. Bolted into rock is about the best anchor system bar none.



I vote for anchors in the rock, and pour the concrete.


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## 7acres (Dec 20, 2016)

They called back to say FlexRack has no inventory till Jan 20th. So they're going to try to make something work with the Schletter rack. They are in discussions with their structural engineer on the best way to mitigate this to make it work and up to code. 

In looking at FlexRack's website I got the impression that Schletter makes a slightly higher quality product. That may not be true at all. But I'm happy to be sticking with Schletter.


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## semipro (Dec 20, 2016)

NateB said:


> I vote for anchors in the rock, and poor the concrete.


A serious consideration.  
At more than 150 lb/cubic foot it won't take much granite to create the required ballast.  The rock could be drilled to determine its thickness, or at least that you have the minimum to provide the required weight.  Then anchors could be installed in the holes with epoxy.  You'd may end up with a better foundation than was originally planned.


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## Karl Hungus (Dec 20, 2016)

We are putting a 9,900 watt system on a new home build. The panels are roof mount on a workshop that's about 80 ft from the rest of the stuff is in the basement of the house. 

The original plan was to run behind the grid. But at the last minute our power co. made a edict, no more behind the grid. So now I have to sell back to the power co. Because we have batteries we are in control of our power we generate. Otherwise without the batteries we'd be selling all our power back to the grid. If the power went out we'd be without power even tho we have the ability to generate power. We didn't like this. Our goal will be to be able to live without the power co. If its close we might just buy a few more batteries and pull the plug.

Our system has 30 panels, 2 inverters, 8 6v batteries that store 38kwhs, automated hydration, 2 charge controllers all tired together with a communications hub for remote viewing and parameter adjustment. Total price installed is approx 40K.
After rebates/tax credits we are paying approx 26K.

House is all electric, very energy efficient. Approx 2800 sq ft living space. Energy audit est 20Kbtu/hr to heat the place. For heat we have a air source heat pump with a 5kw backup electric res. heat coil. But we also have a 2 story masonry heater that we plan on using to heat the place, the heat pump is for backup. Hot water is also a air source heat pump.

Solar system is partially installed, the panels will be going on in the beginning of the new year.
Hopefully will be up and running in Jan.


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## peakbagger (Dec 20, 2016)

semipro said:


> A serious consideration.
> At more than 150 lb/cubic foot it won't take much granite to create the required ballast.  The rock could be drilled to determine its thickness, or at least that you have the minimum to provide the required weight.  Then anchors could be installed in the holes with epoxy.  You'd may end up with a better foundation than was originally planned.



My assumption was similar, given that apparently sound granite was found at similar depth at all holes I assume it is a solid piece of ledge. In my mechanical construction career in NH we encountered granite frequently and on occasion it was far shallower than expected. We generally did preliminary boring before excavation that would give us an opinion on the quality of rock we would probably hit. If it was solid we would end up drilling into the granite and inserting rebar with epoxy adhesive into the hole then forming up our footings and tying the anchor bolts into the rebar with appropriate overlap. I did this with multistory pipe racks that were subject to lateral (side to side) loading.

Given that the solar panel racking is most likely subject to wind uplift as the primary loading I think the easiest approach would be to cut the supplied struts and weld on baseplates or install bolted on angles to the struts and then bolt them to the granite by drilling in a reasonable embedment length and using a suitable epoxy anchor. The limitation with this approach is that the lateral support on bolted on struts is not great as it potentially acts as a pin connection. If a base plate can be added to the strut and several bolts can be installed, the lateral support is definitely increased to closer to a moment connection with far stiffer lateral support.

The devil is in the details, if its thin wall strut (similar to unistrut) it would need to be an engineered baseplate as I would not trust just a weld at the base. I don't have a structural stamp or a license in SC so it comes down to what is acceptable to the manufacturer of the racking system so that they retain liability for the overall racking design. This is a common occurrence and I expect they offer some off the shelf solution but there will most likely be a cost purchase different legs. On the auger style systems I have driven by, the contractors appear to put in the posts and rough them to a set height using a rotating laser as a reference. If one gets too high they can cut them off but the racking system has adjustments for some vertical misalignment.


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## 7acres (Jan 2, 2017)

Update: The work resumes tomorrow (Tuesday). The footers are all prepped with a rectangular hole for each post with, rebar and some welding. The next step is pouring the concrete. They were hoping the concrete company could fit them in Friday but I guess everyone else in the area was hoping the same thing. After the concrete goes in it will set up for 48 hours. So I guess we will only have two working days this week. Progress seems slower than I expected. But I've never been around a solar project to know. Plus we hit a brick wall (err... granite wall) and that is nobody's fault. Anyway after this concrete is in I'm hoping the rest is all downhill from there.


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## peakbagger (Jan 2, 2017)

I would expect that this foundation phase is the slow spot in the project as its every foundation can be different. I expect once you get into standardized PV construction the contractor will speed up considerably


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## mol1jb (Jan 11, 2017)

7acres said:


> Update: The work resumes tomorrow (Tuesday). The footers are all prepped with a rectangular hole for each post with, rebar and some welding. The next step is pouring the concrete. They were hoping the concrete company could fit them in Friday but I guess everyone else in the area was hoping the same thing. After the concrete goes in it will set up for 48 hours. So I guess we will only have two working days this week. Progress seems slower than I expected. But I've never been around a solar project to know. Plus we hit a brick wall (err... granite wall) and that is nobody's fault. Anyway after this concrete is in I'm hoping the rest is all downhill from there.



Any news?


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## 7acres (Jan 11, 2017)

mol1jb said:


> Any news?


Yes! Here's some pics of the big beautiful arrays still going in! The just mounted the last panel today.


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## 7acres (Jan 11, 2017)

I'm super stoked at how they look from the road. They are pretty massive up close but from the road they don't dwarf the house or anything. I'm quite proud of the new look.


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## mol1jb (Jan 11, 2017)

7acres said:


> I'm super stoked at how they look from the road. They are pretty massive up close but from the road they don't dwarf the house or anything. I'm quite proud of the new look.



Ya in the road shot they look great. How much land do you have? Looks like a nice plot


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## jebatty (Jan 12, 2017)

Truly beautiful. Here's a little eye candy for you, a chart of our solar production yesterday, 39kWh in northern MN. Notice the morning clouds .


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## 7acres (Jan 12, 2017)

mol1jb said:


> Ya in the road shot they look great. How much land do you have? Looks like a nice plot



We're on 7 acres. The front 2 acres is cleared. The part in the picture is about 1 acre's worth.


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## peakbagger (Jan 12, 2017)

Nice racks ! (solar porn )

It does look like a nice install, I agree its going to blend in, after a year or so you wont even notice them except maybe bumping your head when you are mowing the lawn. 

Looks like they are going to get "lit up" pretty quick.


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## 7acres (Jan 12, 2017)

peakbagger said:


> Nice racks ! (solar porn )
> 
> It does look like a nice install, I agree its going to blend in, after a year or so you wont even notice them except maybe bumping your head when you are mowing the lawn.
> 
> Looks like they are going to get "lit up" pretty quick.



Haha! Yeah, they told me yesterday to watch out for the undersides especially as the undersides of the panels are more susceptible to damage than even the top side. I will have to really watch out when mowing. Not only of the mower discharge but the roll bar on the zero turn is always out-of-sight out-of-mind. But it will hit low tree branches and stuff if I don't remember it's there. Maybe I'll just put down weed fabric and mulch behind each rack. I'll have to think about that one. 

I'm looking forward to enjoying them as a feature on the property.


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## peakbagger (Jan 12, 2017)

Those panel corners are quite painful and sharper then one would think, after getting impaled a few times when I was installing my system. I wrapped them in foam until I was done. It worked but was ugly. With kids around I would consider putting in some protection on the lower corners if the array isn't fenced in. I see someone on Ebay sells them http://www.ebay.com/itm/Solar-Panel-Corner-Protector-Set-Universal-fit-/321699356740 not sure how long them would last but might save a doctor visit.

I did have issues when I first installed the array that rain running off the lower panel edge was eroding the freshly planted grass. I put in row of stones and that took care of it. Once the grass was established for a year it wasn't an issue.


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## 7acres (Jan 14, 2017)

That's a good tip, Peakbagger about the corner protectors. 

The install is basically done now. The County building inspectors are now scheduled to come out on Tuesday and conduct their inspection. After that the Utility will be inspecting. 

So how about that? Just a few months ago I was on this forum dipping my toe in the water about whether to pursue this. And now the solar is in!


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## 7acres (Feb 7, 2017)

We were energized yesterday! It was very cool to see the meter running backwards. I'll have a full day's worth of production to report today. I can't wait to see the next electricity bill!


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## peakbagger (Feb 7, 2017)

Congratulations, and now the obsession phase begins. I remember those days, checking the daily output and charting it, trying to guess why the output was low one day compared to another. There are some folks on this site that seem to stay in that mode but I think most folks tend to forget about it after awhile. About I do is keep an eye on the LEDs when I walk by to see if they are green and enter my monthly production on my SREC brokers website so I get a check for SREC sales (not not all states have a SREC market but given the incentives you got I wouldn't complain)

One thing you do need to keep an eye out for if you are on an old rural electrical system is that the utilities sometimes have some pretty crappy power quality. The inverters will only synch with the grid within a preset range of voltage and on occasion other loads in the systems may "sag" the voltage so your inverters trip out. If you see times where the system stops generating for 5 minutes and then comes back on line, odds are its time to call the power company and insist they put a power quality meter on your incoming power line. Usually they will figure out what is going on and the problem will go away. There is also a chance that the fraud department of you utility may start sniffing around as your major shift in power usage is a symptom of fraud as well as solar. They usually figure it out pretty quick.


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## 7acres (Feb 7, 2017)

Ooh, wow. Good to be aware of. I don't remember having brownout conditions on any frequent basis. But I'll definitely keep my eye out. Yes, the obsession phase is in full swing! I even drive past my driveway now to behold the panels from just down the road where they are visible. Then I do a U-turn and behold them again as I drive back to my driveway


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## jebatty (Feb 7, 2017)

A real accomplishment for you. I've had the micros trip out on grid voltage being too high, and also shut down on excessively cloudy, dark days; only to wake up again when the sky lightened up. I still check my micros (website view) regularly to make sure that all are OK and output of each micros, as adjusted my shading, is about the same as the other micros.


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## jebatty (Feb 9, 2017)

How were your first days of PV? Sunny or cloudy? Yesterday, Wednesday, was stunning in northern MN: 64.98 kWh. Clear but  slightly hazy sky, except for a cloud that passed over a little after noon, and cold, high was 10F.


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## 7acres (Feb 9, 2017)

That's some amazing output for Winter time, jebatty! Yesterday was patchy clouds all day we got ~25kWh for the day. Previous day was cloudy & rainy and we got about 17.5kWh. The graph on the app looks like a row of shark's teeth with the cloud bands going over.


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## CHeath (Feb 13, 2017)

yes, keep us posted on what shes making on a full sun day. sweet setup. Here in NC, the state was offering 35% on tax and feds 30% but I didnt jump on it. 3 kids and college starting up. Maybe they will do it again before I die lol.


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## lml999 (Feb 13, 2017)

CHeath said:


> yes, keep us posted on what shes making on a full sun day. sweet setup. Here in NC, the state was offering 35% on tax and feds 30% but I didnt jump on it. 3 kids and college starting up. Maybe they will do it again before I die lol.



Check your output meter on a clear night with a full moon.

I'm getting as much as 100 watts!


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## CHeath (Feb 13, 2017)

When my "ship" comes in I would love to have 14 sunpro 375 watt panels on a wood shed and 10 of those same on my south facing roof. That would leave just a hair of a power bill. Nice setup!


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## 7acres (Feb 14, 2017)

So yesterday was a pretty cloudless day. We got 36.261kWh for the day. A nice solid monolithic graph. It looks like during the day we were generating 5.75kW. Is that normal for Winter production? That's about 65% for a 9kW system.


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## CHeath (Feb 14, 2017)

7acres said:


> So yesterday was a pretty cloudless day. We got 36.261kWh for the day. A nice solid monolithic graph. It looks like during the day we were generating 5.75kW. Is that normal for Winter production? That's about 65% for a 9kW system.



sounds about right, I have a client with a 5.2kw roof mount and she did only 435kw/h last month but she did say that it starts getting really revved up at the end of march and pumps out nicely until the end of july then the heat hurts it a little bit.


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## peakbagger (Feb 14, 2017)

Easiest way to check output is just punch your location and system info into PV Watts and see what the predicted monthly output is, convert it to days and then compare it to your actual output.


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## woodgeek (Feb 14, 2017)

7acres said:


> So yesterday was a pretty cloudless day. We got 36.261kWh for the day. A nice solid monolithic graph. It looks like during the day we were generating 5.75kW. Is that normal for Winter production? That's about 65% for a 9kW system.



You need to know the tilt angle (altitude) of your array.  If the sun's maximum altitude is different by an angle theta from your array altitude, your max power will be rescaled by cos(theta).

the sun right now is 14°S of the equator, so if you had a latitude tilt (so you are pointed at the celestial equator), theta would be 14° and cos(14°) = 0.97.  If you were pointed 10° above your latitude (to collect more summer resource), then cos(24°) = 0.91, which is still way above 65%.

I'm guessing branch shading, which is easily 50%.

--------------------

Ok, it seems you are reporting something else....how did you get 5.75kW?  Is that peak?  if your peak was 5.75, and your day was 12 hours long, you would have gotten 1/2 * 12 * 5.75 = 34.5 kWh (if the power was a sinusoidal peak).  ?


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## jebatty (Mar 18, 2017)

7 acres, haven't heard from you in over a month. How's the PV doing? I hope you've had some sunny weather. March in northern MN has been really good so far. Four days over 80kWh with two weeks to go, about 1.75kWh per panel for 265W and 270W panels. The Aurora micro-inverters are conservatively rated at 250W DC maximum output and 265W DC maximum usable input power. The data consistently shows output power in the 255-265W range in the 11:30-1:30 time range.


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## 7acres (Mar 18, 2017)

jebatty said:


> 7 acres, haven't heard from you in over a month. How's the PV doing? I hope you've had some sunny weather. March in northern MN has been really good so far. Four days over 80kWh with two weeks to go, about 1.75kWh per panel for 265W and 270W panels. The Aurora micro-inverters are conservatively rated at 250W DC maximum output and 265W DC maximum usable input power. The data consistently shows output power in the 255-265W range in the 11:30-1:30 time range.



Hi jebatty,
  We have had a few sunny days. Lately we broke a record. We had seen good days topping out at 40kWh. But we got a couple 44+kWh days recently. 

  Is this what we should expect for a 9k system? The per hour stats show 5kWh on a sunny day.


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## jebatty (Mar 18, 2017)

It's difficult to give an answer on what to expect. Your latitude is important and yours is different than mine. Local weather patterns also play a big role. What is the wattage rating of each of your panels?

Look for others with PV in your area and start to talk to them about what their experience is. I have a friend about 17 miles from me with a nearly shade-free ground mount 8kW system, mine also is nearly shade-free, and we compare frequently, but often cloud cover is different for him than for me. On clear days that cover our whole area we get the best comparisons.


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## georgepds (Mar 19, 2017)

Fwiiw.. my latest 3 kw just came on line, bringing me to 7.6 kw ( a little less ac since I use enphase microinverters ..18 m215 and 10 shiny new s280)

I'm getting ~49 kwh on the sunny cold days up here on the Ma NH border


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## 7acres (Mar 20, 2017)

This makes me question whether my setup was done right. Your 7.6kW system generates 49 kwh on a good winter's day. The best my 9kW system has done was 44kW this winter so far.


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## peakbagger (Mar 20, 2017)

I wouldn't jump over the cliff yet. Way to many things can impact solar production between specific sites even without taking into effect yearly local climate variation. Panel angle is big one. Someone with a roof mount is pretty well stuck with whatever angle they already have and that can mean a  steeper than optimal summer angle that boosts production around this time of year. Your system being ground mounted may be more ideally angled so that you get more total power year round. I have a roof mount that is far too flat for this time of year so its production is lower than my pole mount. As the days start to get longer into summer my roof mount starts to catch up and exceed the pole mount although some of that gain is offset by heating as the roof mount definitely is hotter than the pole mount which reduces panel efficiency.


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## georgepds (Mar 20, 2017)

7acres said:


> This makes me question whether my setup was done right. Your 7.6kW system generates 49 kwh on a good winter's day. The best my 9kW system has done was 44kW this winter so far.



Here's a picture of peak power on St Patrick's day. The 10 expansion panels are 305 W connected to s280, the roof panels are 250 W connected to M215 microinverters ( which put out up to 225 W). The system is putting out 6.81 kW, which is close to the maximum, given the microinverter limits, of 6.85 kW.

I only get peak power during the cold March months. The smooth power curve shows it was sunny all day. For the day  I had a total total energy of 49.2 kWh ( Also shown is a snapshot of energy per panel for the day.. the low energy panels near the top of the roof are near the chimney and are shaded in the morning and afternoon respectively)

Just a note.. some say microinverters are really not needed if shading is not an issue.. I find them invaluable in figuring out what is going on with my   system


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## 7acres (Mar 20, 2017)

That's pretty cool you can see details for each individual panel.


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## georgepds (Mar 20, 2017)

7acres said:


> That's pretty cool you can see details for each individual panel.



Cool indeed.. you can play the power view as a video and watch the panels change color as the sun comes up, or as the chimney shades them. You can do it by day or by week

I originally got it because I wanted to be able to track which panel went bad, if any, on the roof. I kept it for the ground mount because I expected some shading in the morning on the bottom row, but mostly because I liked the interface so much


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## georgepds (Mar 20, 2017)

Here is a slide with lifetime energy. The system grew with time.. first 10 (250 W) panels went in ~ December 2012, the next 8 (265 W) on  June 2013, the final 10 (305W)  on March 2017

I post the slide so you can see how energy varies during the  year. From June 13 to early march 17 the system was 4.6 kW DC (4.05 kW AC because of microinverter limits) ). Peak energy per day is ~ the beginning of May and is ~33 kWh / day for the 4.6 kW roof system, this peak energy is pretty consistent from year to year

You'll probably see something like this as you track your energy over the course of the year


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## jebatty (Mar 21, 2017)

georgepds said:


> Just a note.. some say microinverters are really not needed if shading is not an issue.. I find them invaluable in figuring out what is going on with my system


 I agree. I'm not sure how easy it would be to identify under-performing panels with a string inverter installation.

I have Aurora Power One micros, and info is available similar to that which georgepds gets with Enphase. Here is a screen shot of March 15 production, my highest day so far in 2017: 84.76kWh, 1.84kWh/panel average. The 26 panels to the left are 265W, the 20 panels to the right are 270W. The micros are rated at 250W, but actually produce sustained output up to about 265W on cold, clear days in April-May.


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## peakbagger (Mar 21, 2017)

I agree if someone without peak hour shading issues (usually 9 AM to 3 PM) wants to see panel by panel performance, cant beat microinverters or Solar edge Optimizers. On the other hand most folks really don't care once the system has been in operation for a year or so. Realistically barring bad installation or vandalism, PV panels wired in strings are pretty darn reliable, the vast majority of the time the micro inverter monitoring software is flagging a problem its identifying which micro inverter died. Good to know if someone elected to go with micros or optimizers but why not cut out the most failure prone part of the loop and get rid of the micro inverters or optimizers ?.

I went through the economics on micros on another thread (post #68 https://hearth.com/talk/threads/get...r-potential-with-aerial-imaging.160937/page-3) and seem to have come up on a similar system that the micros add $2000 to the cost of a system. Lets use 20 cents per KW for power pricing, that's 10,000 Kilowatts of production that is going to have to be justified in extra production.

The OP has two SMA string inverters that have 3 MPPT inputs available each, given the number of panels I would guess they used 2 on each string inverter. I haven't seen the SMA monitoring software but expect he can see the performance of each string. Pretty easy to compare all four and if one is performing poorly its time to go looking for issues on that string. Odds are the string is disconnected and the output will be zero. If there is a problem with a panel, the easiest way I have heard of is wait until a cloudy day and shine a strong focused light on each panel in the string and have someone record the wattage increase at each panel. The panel with an issue will be the one with least wattage rise. Unless the panel is defective the other rare cause is a smoked diode which on most panels is not readily replaceable. All the micros and optimizers do is electronically jumper out the bad panel and let the rest of the string produce power.

So barring shading issues,  the OPs system most likely worst case loss is 25% of his daily output. Lets assume  40 kwh per day, so 10,000/40*.25) which is about 1000 days where an optimizer would help if a string were out before the extra cost was justified. The trade off is proprietary equipment and wiring from two companies with significant financial issues that could take them out of the picture soon.


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## georgepds (Mar 21, 2017)

Regarding microinverters

Yes they cost more, and yes solar is pretty reliable..but a few thoughts

Most of us don't do solar because of finance, though it is becoming more reasonable to do so

Next, for those of us with bad knees and a roof mount... consider the bad panel...You have to go up on the roof and
 one by one dismount the panel and test the output ... Now consider that task in the dead of winter 

Finally.. it's just fun to look at the output and figure out what's happening, even four years into ownership.

Or... you can count your nickels.. until that rare panel fails on your roof.. then break out the harness and cleats


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## peakbagger (Mar 21, 2017)

The OPs install is a ground mount.

At some point if the micro is bad which is far more likely than a panel, someone still has to climb on the roof to replace either the panel or the microinverter/optimizer. In either case the panel needs to be removed.


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## georgepds (Mar 21, 2017)

peakbagger said:


> The OPs install is a ground mount.
> 
> At some point if the micro is bad which is far more likely than a panel, someone still has to climb on the roof to replace either the panel or the microinverter/optimizer. In either case the panel needs to be removed.



And I bet he'd like to know right now if it is a bad panel, or shading, or cloudy days, or any of the other questions you can answer with a microinverter.

But didn't you propose somewhere that at most it is a 25% loss...after spending all that cash on a new system..I know I'd like to know more exactly what's going on

As to microinverter reliability you have mentioned that several times, but should one go out... you know which one... 

And in my personal experience, I've never had a microinverter fail, but I did have a string inverter fail. Guess what... replacement cost was higher than a microinveter.. and the whole shebang went down, not just one panel.

 Gradual reduction of system performance with single component failure is an important part of system design. You can accomplish that goal with microinverters, but not with a single string inverter


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## 7acres (Mar 21, 2017)

I've got two Sunny Boy 5.0-US inverters, one for each string.

The PVWatts calculator says my system should produce almost exactly what I'm seeing right now. So I'm not worried. I think peakbagger is spot on as far as what to expect from different systems designed around different situations.

As far as inverters go, I'm just happy Sunny Boy made my units in the color *GRAY* instead of bright *RED* like their previous models. What an eyesore that would have been.


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## georgepds (Mar 21, 2017)

peakbagger said:


> ....
> 
> The OP has two SMA string inverters that have 3 MPPT inputs available each, given the number of panels I would guess they used 2 on each string inverter. I haven't seen the SMA monitoring software but expect he can see the performance of each string. Pretty easy to compare all four and if one is performing poorly its time to go looking for issues on that string. ....



Good point.. OP is that the case?
Can you see if one substring is under performing?
Can you track it by hour, or just by day?

Merging multiple panels into substring will obscure the problem, merging data into daily output will obscure it more.. but it is still worth looking into..

Here is an example.. if you look back at my ground panels the bottom row produces consistently less than the top on the daily energy chart. (2.03 instead of 2.10kWh, per "string" 10.5 kWh vs 10.15 kWh)) . If I playback the data I can see that the power is just a bit lower early morning before 8 (house shading) . Nothing I can do about it (I'm not going to tear down the house, and I'm not going to remount the panels). I'll  just accept the lower .
performance.. but I know exactly why it's there


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## 7acres (Mar 21, 2017)

georgepds said:


> Good point.. OP is that the case?
> Can you see if one substring is under performing?
> Can you track it by hour, or just by day?
> 
> ...



I can track it by hour. I can see the exact energy production on each inverter's display panel. They are usually very close. For instance, right now:

Front string:
P: 2430W
E-Total: 655.5kWh

Back string:
P: 2435W
E-Total: 670.8kWh


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## 7acres (Mar 21, 2017)

Here's my PVWatts report:


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## georgepds (Mar 21, 2017)

7acres said:


> I've got two Sunny Boy 5.0-US inverters, one for each string.
> 
> The PVWatts calculator says my system should produce almost exactly what I'm seeing right now. So I'm not worried. I think peakbagger is spot on as far as what to expect from different systems designed around different situations.
> 
> As far as inverters go, I'm just happy Sunny Boy made my units in the color *GRAY* instead of bright *RED* like their previous models. What an eyesore that would have been.




Glad you figured it out.

I'm just curious about angle of panels. From what I understand, most fixed installations have optimum performance near spring.. Did you play at all with the panel angle in PV watts to see if annual ( or spring) production would be more or less?

--g


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## 7acres (Mar 21, 2017)

The above report is based on my 30 degree angle. I just plugged in 20 degrees to see what that would produce. Result: 12,769kWh. So my 30 degree angle is better. 40 degrees produces 12,909kWh; slightly less as well. 35 degrees produces 12,989kWh; super close, but still less. It looks like 32 degrees would give me 13,000kWh which would be an improvement. But now we're probably splitting hairs. That was a fun exercise though.


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## 7acres (Apr 6, 2017)

Got our first all solar electricity bill. $38.28/mo  Woo Hoo!


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## jebatty (Apr 7, 2017)

I remember my anxious/excited wait for the first all solar electric bill which would have arrived in December 2013. My amazement not only of producing electricity without doing anything never ceases, but also getting a monthly "dividend check" from a purchased product, rather than incurring a monthly expense, bring great satisfaction. Also, can't overlook the many  breaths of absolutely clean fresh air the PV provides every day.


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## jebatty (Apr 7, 2017)

My system for Jan-Mar 2017 is in near record-breaking kWh territory. The graph (red-2014) shows highest production, (blue-2016) lowest production, (brown) three-year average production, and (green) 2017 Jan-Mar production. The first six days of April remain at record-breaking levels.


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## peakbagger (Apr 7, 2017)

To paraphrase John Hannibal Smith (The A Team) Don't you just love it when a plan come together!


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## Where2 (Apr 7, 2017)

7acres said:


> Got our first all solar electricity bill. $38.28/mo  Woo Hoo!



My projected bill this month is $35. Not bad considering we've had temps over 90° already.
My worst electric bills last year were two back to back months of $63. 
My worst bill the previous year was $85. (PV array went online 8/2013)
Gone are the days when my August/September electric bill was >$150, and sometimes over $200. 
Before solar went on my roof, I used to have ~6mo/yr with bills >$100 in this all electric house. Now, my roof is shaded by the array, and the array pays to run the A/C system.



peakbagger said:


> To paraphrase John Hannibal Smith (The A Team) Don't you just love it when a plan come together!



Plan... I just love it when the sun comes up!

Microinverters: I can watch the shade from the royal palm tree in my neighbor's yard east of my array tracking across the panels in my array every morning. It clears up by 11AM.


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## peakbagger (Apr 8, 2017)

My monthly bill is about $12.50 a month to cover transmission and distribution plus an arguably illegal state tax on my net metered power coming back from the grid. It might be 35 cents a month when I am pulling back a lot of power to heat my house in the winter but not worth suing. I sell SRECs which usually net about $200 a year so that offsets the monthly utility fees (if I was in Mass I would be getting about $1,200 a year for SRECs).


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## 7acres (May 8, 2017)

Last months bill is in. $14.88.


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