Solar Panel Update - How close to expected?

Happy New Year everyone!  Well, now that the new year is upon us and I finally have a full month of data collection, I can look at how well my solar installation has performed compared to what was expected.  Be mindful that this really only 1 month of data.  The true test will be once we get a full year of data.  But I'm gonna show y'all anyway.


First let's get some of the background, shall we?  Below is a pic of what PV Watts estimated my house should get.  This is the same information that my Solar Contractor, Greenspring Energy, gave to me.

PV Watts Information

 The PVWatts information has a big ole' asterisk with it though.  This assumes full, unimpeded access to the sunlight.  Well, my house isn't in the middle of a field, so these numbers are not realistic.  That's where the SunEye report comes in as shown in the pictures below.

Monthly SolarEye Information

As you'll notice, due to shading, I should expect at most, 75% of the unimpeded values with February- October getting the best results (72-83%) and November-January getting significantly lower (47-66%).  December is the worst month with only 47%.

Wait...never seen one of these things?  Well, essentially what they do is take this fisheye camera thingy (yes, "thingy" is a technical term) and put it on multiple points on your roof where it takes a picture and overlays how the sun will track across it.  See the picture below:

SunEye Report for One of my Locations.

In my case they took 3 pictures at the 3 points of the triangle of my southern facing roof.  In the picture above (the peak of the triangle, best location) you can see how the tops of the trees (green) partially inhibit the sunshine from reaching my solar panels.  The evening trees (picture right) are in my backyard and is about a 50/50 mix of trees in my yard and my neighbors yard.  So if I wanted to increase my energy generation, I'd need to get myself a chainsaw.  However, I don't want to do that because those same trees shade my house and keep the temperature down.  I'll take that benefit instead.  If there was one thing I'd do would be to trim some of the those top trees that are significantly reducing Nov/Dec/Jan.  That could be really only 3-4 branches.  In one instance I know there's a tree that's dead on the top (shown in the pic above, the green splotch where the 10am line and Nov line meet) that probably needs to be trimmed or come down soon anyway.

OK...enough of that tangent...so getting back to the discussion, now let's look at my generation (from the Tigo website):

Tigo Energy Recordings

Overall I've produced just shy of 100 kWh/month for November and December.  And don't forget that I'm missing about 6-10 days of data as the system was energized on November 7th and wasn't fully operational until November 11th.  So let's take this data and compare it what was expected:

Comparison of Expected vs Actual Solar Power Generation

As we see for December, I was just over what was expected for the month which is good! If we were to extrapolate November we'd be a little under (say 130 kWh vs 145 kWh), but it's at least in the neighborhood. I'd say "so far so good".  I think what's going to be most interesting is when we get into this Spring.

I'll try to remember to post this similar information for each month in addition to my Duke Energy information.  If I can, I'll try to combine the two when I can.

Any thoughts out there?

Energized!

View of my solar panels

So my panels are up and running.  Last Thursday the folks came out and flipped the switch to start producing power.  And of course it had to be an overcast day.  And the next day it rained.  Such a bummer.  However, last weekend (and today) the sun is shining and I'm producing some power!  I checked it multiple times this weekend and I myself producing about 1.1 kW of power. Cool!

Zero Watts.  So disappointing...

The Tigo system is hooked up as well.  I can't say much about it because I still haven't gotten my login information so I can view what's going on.  And the unit at my house won't give me any information until it connects with their servers online.  What a drag!  Greenspring told me this was supposed to be done Thursday and I'd get the login information on Friday.  Well...it's Monday and still nothing.

Tigo Unit not telling me anything.  Boring...

Overall, I'm happy with the install.  That being said, I have a couple of critiques for Greenspring Energy:

1)  Be honest with the payback.  They gave me the information from PVWatts, install costs, and then estimated an ROI.  Here's what they didn't provide:
    a)  No Tax was included.  That was another ~$500 on top of the install cost.  $500 is roughly 2 years on the ROI.
    b)  Be realistic with the Duke Energy rate increases.  They used 5%/yr.  Yeah...that works for the last, oh 5 years.  But long term, it's been closer to 2%/yr.
    c)  If you conduct a solar eye, then adjust your power generation numbers! I had to ask if they did a solar eye and then ask for the results.  When I read the results, I found out that the actual estimate for power was 20% lower than what PV Watts was estimating, because it assumes an unimpeded ideal southern exposure.  I don't have that.
   d)  Solar panels degrade.  It's even one of the selling points by Sunpower...that it retains ~95% of its power after 5 years and 85% after 25 years.  That's a 0.25%/yr degradation (industry standard = 1%/yr).  Fantastic...well you gotta include those calculations in your ROI!  
   e)  Overall, my ROI was estimated at 13 years.  There's was much better.  Anybody Surprised?
   f)  Hopefully this changes, as I showed them the U.S. DOE System Adviser Model (SAM).  This model includes all the information I note above (except rate increases as user entered).

2)  I would've thought a high priced install would have looked nicer?  The panels themselves look nice\, but some of the other aspects could have been more professional looking.
  a) Below are some pictures with the install.  I'm a little disappointed that I now have a long conduit pipe running down the side of my house.  I will say that at least it's kind of hidden as it runs along the soffit. I'm probably going to have to paint it so it will blend in a little better.  Granted my breaker box isn't exactly located in the easiest place to get at. But, I will say that the wires could have been run down to the crawl space and then come out to the inverter.  I can't complain too much about it.  It definitely could have looked worse.  Judge for yourselves:

Conduit running along the side of the house to the inverter

  b) Next is the TIGO install.  Check out the wires.  Looks like of sh*tty, right?  When they were there I inquired about the wiring and they were offering to get one of those cheap-o black cord holders.  Appropriate thought, I'll give them credit.  But seriously...make it look nice.  Thus, why I went and purchased the nice wire hiding stuff.  And I may go further and have it go into the wall first, and then pop out and run along the base.  I'm not sure yet

Tigo wiring At least they put on wire ties, right?

Then there's where they came through the wall to hook up the communication to the panels via ethernet (gray wire). They ran it through the upper attic, then down to the bonus room attic knee wall (like I did when I wired the house for ethernet).  However, they just cracked my base plate and ran their wire behind mine.  Really?  You couldn't spend the $2 to buy a new plate to run it through?  And then in my bonus room attic, I spent a lot of time and effort putting up XPS insulation and sealing everything.  They just drilled a hole and ran the wire through...leaving a direct hole from the attic to my bonus room.  Couldn't even take the time to put at least piece of HVAC tape over it?!? (I did that temporarily)  Well...once I get the wire chase installed, I've already bought the new plate with the hole where I'll have the wire will run through.  And when that's done, I'll fill in the hole with the XPS with great-stuff foam.  I think I may still have ethernet materials left over....and if I do I may install an ethernet jack instead to make it look much more professional.

Wire coming through the back of the plate.

Once I get the TIGO login information, I'll post about it.  It's pretty cool stuff.

Oh...and I had to buy another adapter kit for my TED 5000.  Apparently it won't register less than zero...or I should say when it does it still reads a positive value.  So to correct my TED readings, I've had to spend $100 on a new MTU (transmitting unit) so I can measure the PV generation individually and then TED will subtract those values from my overall to give me a net (+/-) value.  I'm a little disappointed in this, but oh well.  I should have looked this up previously.

Stay tuned for more fun info!