My 10.1KW System

dwh · November 2010

Re: My 10.1KW System

As we say on the Information SuperInterWebs - gratz!

niel · November 2010

Re: My 10.1KW System

that's great news.8) about time huh? just like a kid waiting for santa claus it just wasn't soon enough, but such a relief when it was put in and activated. let us know how well it does.

solar_dave · November 2010

Re: My 10.1KW System

Yep pretty cool when it all happens, congraties on the final.

Energy Efficiencies · November 2010

Re: My 10.1KW System

Solarseeker wrote: »

Mr Radon- You do GREAT work! Those flashings look awesome.

I guess, my point is that I thing the flashing looks beautiful, but will it last as long as your system? Did you investigate this issue beforehand? If not, can anyone else answer this? Thanks!

I am not a rocket scientist, but tin lasts much longer than asphalt, doesnt it? I am certain it will be fine.

mr.radon · November 2010

Re: My 10.1KW System

The flashing is Aluminum not tin. The roof is good for another 15-20 years, should not have an issue for some time. I looked at a re-roof before hand and even got a local roofer to look it over for me. I and the roofer came to the same conclusion, wait to replace the singles.

So I figure in 2025 I'll be posting how to remove the PV system, reroof and then reinstall the PV system.

On a side note, the Seattle area was hit by a massive cold front that brought snow and sub 20F weather. I've had snow on the panels for three days now. Is there a good way to get the snow off? I check the panels, under the snow is a layer ice.

My plan is to just wait till the rain returns. I've noticed a huge drop in production with the low sun, short days, clouds and winter rain. I'm only averaging 2-3Kwh/day.

drees · November 2010

Re: My 10.1KW System

mr.radon wrote: »

On a side note, the Seattle area was hit by a massive cold front that brought snow and sub 20F weather. I've had snow on the panels for three days now. Is there a good way to get the snow off? I check the panels, under the snow is a layer ice.

I haven't had any experience with it, but from what others have said once the sun comes out and hits a bit of the panels it will quickly warm them up enough to melt the snow off the panels as long as you have sufficient angle on the panels and nothing blocking the snow from sliding off.

I imagine that clearing at least a small portion of the panels would help speed this up.

mr.radon · January 2011

Re: My 10.1KW System

My system operation compared to PV Watts predictions:
179.99 kwh, Nov 2010 = 6.0, Nov = 7.9, 237.38 kwh
174.78 kwh, Dec 2010 = 5.6, Dec = 4.4, 136.13 kwh
35.76 kwh, Jan 2011 = 8.9, Jan = 6.0, 185.18 kwh
The first number is my monthly production.
The 2nd number is the average kwh/day production
The 3rd number in the PV Watts calculated average kwh/day production
The 4th number is the PV Watts calculated monthly kwh production

I was a little off for November (I extrapolated since I went on line 11-4-2010), am ahead for Dec and Jan so far. Happy with the low sun, winter production so far.

CaptTurbo · January 2011

Re: My 10.1KW System

I enjoyed reading through your install thread. You did a remarkable job. Truly first rate work.

I had a system very close to yours in size installed last Spring. The system has only 44 panels but they are 230 watt Trina mono. My system went on line in mid April but they dragged their feet on installing the net meter until June first.

I guess I'm lucky in location (SW Florida) because the system gets a lot more insolation. A glance at my WebBox shows that the system has generated 12.5 Mwh to date. It was gratifying to see a credit on the last bill to finish the year.

I did do a re-roof before the install. My shingle roof was in good shape but it was 14 years old and here in Florida roofs don't last as long as they would in your area. I went with a gavalume roof so hopefully I will not have to ever do a R&R to replace it.

Anyway, you certainly can be proud of such a fine job on your system. I bet the neighbors are jealous!

jagec · January 2011

Re: My 10.1KW System

newenergy wrote: »

I doubt that kind of failure is possible. I have heard, directly from a utility person, that the lockable disconnect is so they can lock you out if you don't have permission to be grid-tied.

The real question is why they think that someone who DIY'd a grid-tie PV system without utility permission would have installed a utility-accessible disconnect in the first place.

Or that someone who was handy enough to install the system, and devious enough to hook it to a public grid without telling anyone, couldn't figure out a way to break into a sheet-metal box with a cheap padlock.

n3qik · January 2011

Re: My 10.1KW System

The install would be to code/permissions. But later. If a billing/credit problem arises. Then they lock you out.

russ · January 2011

Re: My 10.1KW System

All you need is an irritated neighbor or a kid talking too much - secrets like that often don't stay secret.

What seems cute and OK to you may sound different to the next party.

Russ

System2 · January 2011

Re: My 10.1KW System

CaptTurbo wrote: »

I enjoyed reading through your install thread. You did a remarkable job. Truly first rate work.

I had a system very close to yours in size installed last Spring. The system has only 44 panels but they are 230 watt Trina mono. My system went on line in mid April but they dragged their feet on installing the net meter until June first.

I guess I'm lucky in location (SW Florida) because the system gets a lot more insolation. A glance at my WebBox shows that the system has generated 12.5 Mwh to date. It was gratifying to see a credit on the last bill to finish the year.

I did do a re-roof before the install. My shingle roof was in good shape but it was 14 years old and here in Florida roofs don't last as long as they would in your area. I went with a gavalume roof so hopefully I will not have to ever do a R&R to replace it.

Anyway, you certainly can be proud of such a fine job on your system. I bet the neighbors are jealous!

My system is 44 235 Sharps(10.34 by GATS),2-5kw SMA with (TIGO boxes),on line in April.Elec. Co.took 2 months for meter.6 days snowed o kw's but total so far is 12.71MW Sold 11 SREC's for $7200.No happy faces for Elec.Co here.This forum needs a file or location for systems by Kw size.

RegGuheert · January 2011

Re: My 10.1KW System

mr.radon wrote: »

He did look at my calculations 190W * 45 = 35.625A * 125% = 44.53A He said using a 40A circuit breaker is JUST FINE! This is because they are facing different directions. None will be producing max power at the same time. He bought the explanation. I showed him the PV Watts simulated output and the SketchUp shadow model. He said the NEC Code needs to be re-written on Solar systems. He understands the logic. NEC needs to make exceptions for arrays that face different directions.

FYI, here is a clear picture of this difference taken from the Enlighten page for your array:

attachment.php?attachmentid=1583&stc=1&d=1295617870

Since I do not know how close your roof orientations come to the true compass directions, I will assume they are right on for this discussion:

Since it is 11:34 AM in this picture and based on the production numbers, it appears that the sun is near the boresight of your south-facing array. Of course it is off of the boresights of the east- and west-facing array, but closer to the east-facing array due to the fact that it is not past noon. Do you have any idea why the easternmost south-facing array is producing about 10 fewer Watts per panel than the other one? Are the panels not pointing in the same direction?

There also appears to be a little bit of shading on a couple of the panels on the east- and west-facing roofs. I think you have mentioned this fact elsewhere in this thread.

Thanks for posting your experiences here! I have referred to this thread frequently while assembling my system! Here's hoping your summertime production is MUCH better than what you are getting this winter!

mr.radon · January 2011

Re: My 10.1KW System

Enphase has ignored repeated e-mails to get the angles right on my arrays. The two small arrays in the center, of (4) and (3) panels are facing south.
The array in the upper left (12) are facing East, the arrays on the bottom left and right (16) & (10) panels are facing West.
The E-W roof peak shades the left most east and west arrays shown on the Enphase site in the winter. I also have a gas exhaust that presents a little shading issue. So far the shading issues are exactly what google sketchup showed I would have for this time of the year. However, we are having some of the wettest weather ever. Lots of cloud cover the last three weeks.

Here is the youtube video of the google sketchup shade modeling I did.
http://www.youtube.com/watch?v=JsbKqr_SPrE
It runs through a day of shade for every 12 months.

I know my system is not going to produce maximum power, I knew this going into the project. One of the reasons I went with Enphase was the shading issues I knew I would have. So far I'm pleased with the power output, I just can't wait for the darn rainy season to end. Another three months though.

drees · January 2011

Re: My 10.1KW System

mr.radon wrote: »

Enphase has ignored repeated e-mails to get the angles right on my arrays.

Have you tried calling them? It'd be nice if they'd open up the installer tools to us DIY types...

mr.radon · March 2011

Re: My 10.1KW System

Well after seeing a problem with one of my panels production I cut my gas exhaust pipe down in size. The exhaust pipe shown here is not about a third it height, and no more shadow.
Now I just need the rain to go away...

jcgee88 · March 2011

Re: My 10.1KW System

mr.radon wrote: »

Well after seeing a problem with one of my panels production I cut my gas exhaust pipe down in size.
The exhaust pipe shown here is not [sic] about a third it height, and no more shadow.

This is one of the best features of Enphase's management
software. That is, you can see the effect of a problem hour
by hour at the panel level. Armed with that information,
you can make an informed decision about what remedial
action to take.

As you may remember from an earlier reply-post of mine, I
had the same problem with a chimney flue, and I could see
the flue's small shadow disproportionately affecting harvest
on two panels in early morning. Like you, I finally could no
longer bear the annoyance, and I did something about it!

In my case, I replaced the appliances that used the flue
with side-vented, high efficiency equivalents. This then
enabled me to eliminate the chimney flue completely, and
if solar panels could smile, I am sure mine are now!
[Actually, the new appliances' main benefit is their
reduced energy usage; getting rid of the flue shadow
was gravy.]

By the way, initially, I did look at reducing the height of the
chimney flue, as you did. I found that building codes and
the safety concerns reflected therein precluded lowering
the flue height sufficiently to eliminate the shadowing.

mr.radon wrote: »

Now I just need the rain to go away...

Because you went into production last October, and thus missed
the peak production summer months, I bet you can't wait until
"solar season" arrives!

John

mr.radon · March 2011

Re: My 10.1KW System

I pulled the codes on flue height, so it is now within .25" of code. It was about 14" taller then needed. looked like they just used stock lengths, no trimming. Cap needed replacement anyhow.

I kinda knew this was going to be an issue. Watching that shadow bothered me into action.

I have a on-demand hot water heater, massive BTU output when on. Can't remove the flue, this will solve the issue. That device has saved me 66% in natural gas. I love it!

Frxddy · April 2011

Re: My 10.1KW System

I am new to the Forum and considering a solar electric and enphase system. I just read every word of your installation. You have done a great service by taking the time to show the world your DIY install. Congrats on the great job!

I have one or two questions.... I thought I read someplace that Enphase charges a monthly fee for your information that is posted on their website. Is that true? If so, how much is the fee?
If/when I do a system I will have zero shading through the day. Do you think Enphase inverters would still be a good choice? I know they are a little extra money, and I like the idea that if one dies, the rest of the system still works, but, I guess I'm trying to get a feel for what would be a good choice for me. Are the Enphase inverters silent?

I see a few people have asked about the life of your Oatey flashing. I'm a plumber & I can tell you.... in a normal install at least 25 years, (Maybe less in FL?) but mostly in the shade of your panels I'd think they'd last just about forever!

I know the feds give a 30% credit, but is there also a credit per kilowatt hour produced?

mr.radon · April 2011

Re: My 10.1KW System

Frxddy wrote: »

I am new to the Forum and considering a solar electric and enphase system. I just read every word of your installation. You have done a great service by taking the time to show the world your DIY install. Congrats on the great job!

Thanks...

I have one or two questions.... I thought I read someplace that Enphase charges a monthly fee for your information that is posted on their website. Is that true? If so, how much is the fee?

The monthly fee, free for 90 days. Then there are three options:
1) Let it expire - you can still log into the Envoy, but only to see system status can't get the data but some people are working on that.
2) 1 year subscription - $2.00/module
3) 5 year subscription - $9.00/module
With the fee you also get the 100% uptime guarantee.
I recommend the Envoy. But the subscription, well there are other ways to monitor production. I have other posts on that. With the Envoy you can at least see if there are issues with an inverter.

If/when I do a system I will have zero shading through the day. Do you think Enphase inverters would still be a good choice? I know they are a little extra money, and I like the idea that if one dies, the rest of the system still works, but, I guess I'm trying to get a feel for what would be a good choice for me.

I like the simplicity of enphase. I have used SunnyBoy's on a different installation I did. So between the two, Enphase was much easier. In the long run, failure modes are better with the Enphase modules and the newest ones they have coming out makes it even simpler. However, it is slightly more expensive. My install came in right at $3.60/Watt. I thought that was a good number considering I've heard people spend that much on 4KW systems.

Are the Enphase inverters silent?

Well they make no audible noise. And as far as I can tell they don't create any radio interference. I have a AM/FM radio in the garage right below 27 inverters I don't pick up any interference in the AM nor FM band.
In the attic (as far south as possible) I have two TV antennas to pick up the local HDTV broadcasts from the south - they are directional antennas (this is below my southern West facing 10 panel array). I have no issue with getting signals from Seattle, (32+ channels in all). I have to install the antennas because the solar panels did effect rabbit ear reception, I figure that was more to do with all the hard ware on the roof. With the antennas i now get twice the channels I had before I started the project.

I see a few people have asked about the life of your Oatey flashing. I'm a plumber & I can tell you.... in a normal install at least 25 years, (Maybe less in FL?) but mostly in the shade of your panels I'd think they'd last just about forever!

Thanks, I heard they were high quality and durable from others in your profession.

I know the feds give a 30% credit, but is there also a credit per kilowatt hour produced?

In my state there is a production incentive, for my system it is $0.15/kwh. Every state is different. I would suggest you research your state's laws and contact your utility. most have flyers on programs, incentives and guidance.

I'm an engineer with 20+ years experience. This was a fun project, but mind you each install is unique. This site is a great resource if you ask questions.

mr.radon · April 2011

Re: My 10.1KW System

I figured I'd toot my horn a little as today was a big day for my system.

Well today was the first cloud free spring day. Seattle has had since February 13F below normal and three to four times more rain fall. UGH... Not a cloud free day in months...
Still I have been impressed with my systems operation.
Today I set a record for my system's single day production! 58.7kwh WOW!

Considering I use between 5.5-8.5 kwh/day I'm a happy camper. (can't wait to finish my VW Rabbit EV conversion to use this extra power)

Anyhow, here are the production numbers compared to PV Watts 1/2:

_____Actual Monthly Totals___PV Watts Predicted___
179.99 kwh___Nov 2010 = 6.0__Nov = 7.9__237.38 kwh
174.78 kwh___Dec 2010 = 5.6__Dec = 4.4__136.13 kwh
188.82 kwh___Jan 2011 = 6.1__Jan = 6.0__185.18 kwh
366.34 kwh___Feb 2011 =13.1__Feb =12.2__342.23 kwh
602.07 kwh___Mar 2011 =19.4__Mar =22.2__688.05 kwh
690.48 kwh___Apr 2011 =30.0__Apr =31.2__936.45 kwh

Overall I'm a little low, but given the nice weather, I might be able to make the 246kwh in the last 7 days left in April. I'm well over 1,500kwh NET positive this year. and have almost produced 2,500kwh since I flipped the switch.

niel · April 2011

Re: My 10.1KW System

not bad, but here's to you breaking that record. (glass raised)

i know what you mean about the gloomy weather as i've probably had as many cloudless days since last november (also with an above normal winter by about 30% more snowfall than average) that i can count on my fingers on 1 hand.:grr the soil here is super saturated and we're under constant flood watches and warnings it seems.

Frxddy · April 2011

Re: My 10.1KW System

Congrats on the record day! Wooohooooo! Very cool.

Thank you for taking to time to answer my questions. Next Friday I have someone coming to do a "solar survey" of my property. They have done some local installs and have a good reputation. They say they can do a system, complete, for $5 a watt installed. I was thinking I'd do my own installation, but if they can do a quality system for that price I might just write a check!

Take care & may the clouds shy away from your sky.

Fred

solar_dave · April 2011

Re: My 10.1KW System

Congrats on the record day, does that 10K system get you close to net zero?

@ Fred $5 a watt installed is about the proper going rate lately from What I have seen.

mr.radon · April 2011

Re: My 10.1KW System

solar_dave wrote: »

Congrats on the record day, does that 10K system get you close to net zero?

I'm about 1,500 NET positive right now. I use about 3,000-3,500kwh/year. The rest of my production I plan on using to charge my (future) EV commuter car.

solar_dave · April 2011

Re: My 10.1KW System

mr.radon wrote: »

I'm about 1,500 NET positive right now. I use about 3-3.5kwh/year. The rest of my production I plan on using to charge my (future) EV commuter car.

Very Cool! I have about 2000Kwh positive as of the first of the month and the Chevy Volt should be delivered in the next 10 days! Like minded I see.

Because of the AC loads this summer and the addition of the Volt I have been considering a bit more solar, but I think I will see how it makes out first. Off peak charging is pretty cheap here.

Vic · April 2011

Re: My 10.1KW System

Hi Mr. Radon,

Been following this thread for a while. Thanks for all of the detail. One of your later pix shows the solar rack posts and flashing in great detail.

For a new off-grid array, will need fixed solar racks, instead of the tiltable ground/roof racks that I've customarily used. In looking at one of your photos, it seems obvious that not every of the mounting posts can be lagged into a rafter at every location. Did you use a flat 2X6 or similar at the points where there was no rafter? OR, was it a real edge of a supplementary block, ie, a 2X4 or 2X6, or 2X8 (etc), such that any lag would penetrate the edge of this block ?

My roof construction is 2X12 rafters 16" O/C, with 3/4-inch T&G (real) plywood, but the rafters will not fall in the correct position in numerous places. WIthout using something like UniStrut(r) mounted on posts across the roof (horizontally) lagged into the rafters, and the solar racks running vertically bolted into the strut, or supplemental blocks as needed, I cannot see how to use only rafters or similar as the only attachment points.

Am looking for advice on customary practice. Have not seen this type data on any supplier's site.

My new array will be 20 or 24 SW-245s in strings of four, orientated in Portrait on a 30 degree sloped roof. Would like to increasse the tilt to 35 or perhaps 40 degrees, (fixed), but that is not essential.

Thanks for all of the fine detail on your nice large system, and TIA for any advice you or others have to offer. Vic

drees · April 2011

Re: My 10.1KW System

Vic wrote: »

In looking at one of your photos, it seems obvious that not every of the mounting posts can be lagged into a rafter at every location. Did you use a flat 2X6 or similar at the points where there was no rafter?

He used purlins to bridge between rafters where required...

You can see in post #27 where he has installed some purlins.

Vic · April 2011

Re: My 10.1KW System

Thank you drees,

I had read every post twice, but that had been a couple of months ago. Even scanned through every post, but missed this. Thanks for reminding of this post and the correct word as well.

Thanks, Vic

mr.radon · April 2011

Re: My 10.1KW System

In post #7 I've attached the Pro-E models of the racking system as it lined up with the rafters. Where ever a support did not line up I added a purlin. For me this added some support to the sheathing but was a little overkill. The building code/permitting engineer said I could either do this, add more supports, or spec out stronger beam material.
Mind you I have a heavy snow loading, we get occasional snow fall with super high moisture content, plus nasty wind storms off the Pacific. This was the best solution for my situation: time/cost/weight.
Each case could be different. Have fun with your installation.

My 10.1KW System

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