5 KW Grid-Tie PV Solar System in Mid-Michigan

First let me introduce myself. My name is Scott and I am a Spartan (alum of Michigan State University). I graduated and am employed as a Mechanical Engineer specializing in stress analysis and system design. My job has me designing power plants (gas-fired, coal, nuclear, solar & wind) in the US, Canada, and around the world. I recently purchased a home in Howell, Michigan and have decided to install solar to cover 100% of my electric needs. I will use this thread to share my design and progress. I welcome questions and comments, and I may even have a few questions myself.

System Sizing:

I've only been in the home for 10 months, but I can estimate the yearly electric use at 4000 kWh...but I don't expect to be single for long. Add a wife and kids and it will be much harder to conserve electricity. I also would like to size the system to cover a plug-in kit I plan to add to my Prius this summer. When I upgrade to an electric vehicle in 5-7 years, my electric use will double. I've decided to size the system to my current needs and then double the system when I purchase an EV.

The south facing roof on my house has an azimuth of 153 degrees. The solar panels will be installed at an angle of 33.7 degrees (8:12) from horizontal. PVWatts for my location estimates 5700 kWh per year for a 5 KW system. Due to minor early morning and late evening shading I expect slightly less. I do not have enough power need to justify a 6 KW system.

Equipment Selection:

I would like to buy good quality, reliable equipment that will last long past its warranty period. For inverters I have narrowed down my choice to SMA, Xantrex, and Enphase. Interestingly, installers charge the same for a SMA vs. Enphase system. They say this is due to Enphase being a less labor intensive installation. I do not believe I have that big of a shading issue to where I would want to install Enphase. I have been asking contractors to quote my system with a SMA Sunny Boy 5000US GT inverter.

As for the actual solar panel, I am looking for a 25+ year warranty and asking contractors to quote me using Sharp brand. Specific panel will be decided based on what pricing they can get at the time. For my 5 KW system I will require 18-24 panels, depending on panel size & string sizing etc.

Funding/Cost $$$:

-I will receive a 30% federal tax credit on my 2010 taxes.
-My electric provider (DTE) will give an instant rebate of $2.40 per Watt upon completion of install. Assuming $6 per watt, this is a 40% rebate.
-DTE will also purchase my REC (Renewable Energy Credits) for 20 years at $0.11 per kWh. Assuming that I generate 5500 kWh per year avg, that is worth $12,100, or 40% of install cost. This "rebate" is paid out yearly. Since this is a yearly payout, in an economic analysis I will have interest losses in my invested money.

Add up the three incentives and I will be rebated 110% of my total system cost. I have calculated break-even for my system to be 5-6 years (depending on future interest rates). DTE rebates require me to have the system installed by a licensed installer.

Installer ???:

Over the past 2 weeks I have gotten quotes from over 4 solar contractors using similar equipment. Since each installer is basically a start-up company I decided to play dumb to test the knowledge of each company. What I have found: Quotes range in price from $5.90/watt to $7.10/watt. Electrical companies that are trying to break into the solar business are trying to tell me a 5KW system will give me 7500 kWh per year...WRONG. So far I have only found one company that knows what they are talking about with solar (and their price happens to be $6/watt). I have met with the president of this company twice and he has even offered me a job with them. I have decided to work with this company for my installation. For now I will not post this companies name.

My Current Status:

Monday I will receive a revised proposal/quote. I will then go into negotiation regarding exact parts and wire sizes used. I feel confident that I will be able to sign a contract with them within 1-2 weeks. My current quote is with Sharp 235W Monocrystalline silicon panels (NU-U235-F1). 22 panels for 5170W, 11 panels per string.

My roof is split into 3 elevations. 16 panels will fit on the uppermost (East roof). The remaining 6 or so panels will be put one level down, as high and West as possible. Attached is a picture of my house.

Thank you for reading this & your interest in Solar.
-Scott
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Comments

  • halfcrazy
    halfcrazy Solar Expert Posts: 720 ✭✭✭
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    It sure sounds like you have done your homework. I like your choices so far. Just make sure the racking is installed correctly don't want any roof leaks
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    Also, check out the Prius as a UPS site too.
    http://www.priups.com/exec-summary.htm

    Just have a exhaust pipe vent.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • Northforker
    Northforker Registered Users Posts: 15
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    Scott,

    Good thread, look forward to following your progress. Please post lots of updates and pics!

    I'm probably 6 months behind you on a similiar system in Indiana.

    Thanks for sharing.

    Don
  • SpartanScott
    SpartanScott Solar Expert Posts: 41
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    I met with my installer last night to review and negotiate his proposal. He was nice enough to come by after work hours and spend two productive hours with me. The price of the Sharp 235's jumped up $0.20/watt last week so I have switched to Sharp 224's (ND224UC1). 24 panels split into two strings is what I chose to match up with the SMA 5000 inverter. My design Low temp is -22F, and design avg high temp is +86F. 24 panels x 224W = 5376 Watt System.

    He gave me a full system turn-key price of $6.00/Watt for a total of $32,256. Here are some details of what I got him to include in that price.
    - He increased his parts & labor warranty to a full 10 years (from 7yrs).
    - I have decided to cut the SMA monitoring (Sunny Webbox) and install a more detailed monitoring system. I have chosen the Web Energy Logger system which will cost around $1000. My installer agreed to cover the extra cost, but I will be doing the install.
    - He will allow 25-30% of the system cost to be deferred 1 month, so that I may use the DTE instant rebate ($2.40/watt = $12902) to pay off the system. This means I don't have to come up with 100% upfront cash.
    - As you see in my picture above, there is a roof vent that may cause trouble (or at least be in the way of installing 1 panel on prime real-estate). He has agreed to include relocation of this vent in the price.

    We then went on to discuss timing. It turns out if I were to pay an initial payment today, he can have it installed by this weekend. Wow was I impressed. I guess his company (of 15 people) installed a 14 KW system last weekend with only 5 days notice. I am not looking to rush things that much. For now I will plan on signing, detailed design, and equipment ordering next week. I have set a preliminary install date of March 12th.
  • SpartanScott
    SpartanScott Solar Expert Posts: 41
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan
    halfcrazy wrote: »
    It sure sounds like you have done your homework. I like your choices so far. Just make sure the racking is installed correctly don't want any roof leaks

    For roof attachment he uses the Unirac Flat top 2-piece aluminum standoff, 1 5/8" shaft, with a collared 8.75"x12.5" flashing. Here is a link to the install manual: http://www.unirac.com/pdf/ii907.pdf I will get a spec sheet on the sealant which will be used.

    I have got two pictures of his prior installs. See any quality issues in the standoff and DC combiner box install? Would using QuickMount be even better than the proposed Unirac mount (& how)?

    Thanks,
    Scott
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    Roof mounts on shingle roof look awfully low, and not much air gap for circulation. But you have a steep angle, and maybe that helps keep the panels cool in the summer?
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    i'm confused as to why the rails run vertically in pic 1 and horizontally in pic 2. is this the same roof?
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    I believe they are pictures two different installs by the contractor.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SpartanScott
    SpartanScott Solar Expert Posts: 41
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan
    BB. wrote: »
    I believe they are pictures two different installs by the contractor.

    -Bill

    Correct, this is two different installs. The install method is the same for both jobs though. First vertical run rack is connected to the standoffs. Then horizontal racking is laid to catch each row of panels top & bottom. Looks like a solid design method.
    mike90045 wrote: »
    Roof mounts on shingle roof look awfully low, and not much air gap for circulation. But you have a steep angle, and maybe that helps keep the panels cool in the summer?

    With the standoffs plus two levels of racking beneath the panels, the air gap would be ~7".
  • sub3marathonman
    sub3marathonman Solar Expert Posts: 300 ✭✭✭
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan
    I've only been in the home for 10 months, but I can estimate the yearly electric use at 4000 kWh...but I don't expect to be single for long. Add a wife and kids and it will be much harder to conserve electricity. I also would like to size the system to cover a plug-in kit I plan to add to my Prius this summer. When I upgrade to an electric vehicle in 5-7 years, my electric use will double. I've decided to size the system to my current needs and then double the system when I purchase an EV.
    The south facing roof on my house has an azimuth of 153 degrees. The solar panels will be installed at an angle of 33.7 degrees (8:12) from horizontal. PVWatts for my location estimates 5700 kWh per year for a 5 KW system. Due to minor early morning and late evening shading I expect slightly less. I do not have enough power need to justify a 6 KW system.
    -Scott

    OK, I added the bold print to your quote, but I think you do have enough power need to justify a 6 kw system, and maybe even a bit more. I think the limiting factor should be your roof space. With the price of the panels so low it just makes the most sense. The difference in price from a Sunnyboy 6kw to a Sunnyboy 7kw can't be as much as going back in five years to either replace the 6kw with a 7kw or else add a 3kw inverter. Also, I don't know if you can get another Federal or state rebate if you add to the system or install another one.

    I was limited by the Florida rebate to 5kw, otherwise I would have tried to do more. I did run out of prime roof space though too. With the current prices though, I'm thinking of trying to add three more panels somehow and get closer to the maximum of the XW6048 inverter I have.

    Also, something which was a mistake on my calculations turned out to be a benefit, and that was concerning the wire size. I had to run another set of conduit and wires because I didn't calculate in the equipment grounding conductor. My system is 48V, so it is much more important than with a 500V system, but then I upsized the wires as much as possible to the new conduit size. Once again, there was a price difference, but for the price of the system it made sense to try to get as much out of it as possible, instead of just warming wiring.
  • SpartanScott
    SpartanScott Solar Expert Posts: 41
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan
    OK, I added the bold print to your quote, but I think you do have enough power need to justify a 6 kw system, and maybe even a bit more.

    I was limited by the Florida rebate to 5kw, otherwise I would have tried to do more. I did run out of prime roof space though too. With the current prices though, I'm thinking of trying to add three more panels somehow and get closer to the maximum of the XW6048 inverter I have.

    If I could install a 10 KW system now to cover the energy needed for an electric vehicle, I would. I actually tried but was shot down pretty fast by DTE(local SE Michigan Electric Provider). The qualification to get into their solar program is system size must be less then 100% of your energy use. My 5 KW system is 150% of my current energy use, but they allowed it due to the fact that I can provide them calculations and intent to purchase a plug-in Prius kit this year. Since I could not show and reasonably prove to them which EV I will purchase 7 years down the road, they did not allow the 10 KW system.

    The DTE solar program (SolarCurrents) will be capped after 2500 KW of residential installs, and this is expected to fill up in the next 8-12 months. After that, your right, I will loose out on this 80% rebate if I choose to upgrade in the future. Then there is the question of if the 30% fed tax credit will still be available.
  • Solar Guppy
    Solar Guppy Solar Expert Posts: 1,989 ✭✭✭
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    Tell them you intend to purchase either a GM Volt or Nissan Leaf this year, both can add the EV load your power company wants and both can be bought this year ( Sept for the Leaf, Nov for the Volt )
  • autoxsteve
    autoxsteve Solar Expert Posts: 114 ✭✭✭✭
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    Scott,

    Have you considered Evergreen panels? I am quite pleased with their performance.

    Looks like Michigan is offering a great deal for you to take advantage of.

    I too had ran into a problem of the state rebate here in Kalifornia not covering systems that were sized larger than my usage. I wished I had put another 2 panels up. Since installation I had added an electric water heater and the extra 2 panels would put me back in the surplus. Oh well I'll have to find another way to converve!

    Good luck to you and I'll be following your progress!
  • SpartanScott
    SpartanScott Solar Expert Posts: 41
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan
    Tell them you intend to purchase either a GM Volt or Nissan Leaf this year, both can add the EV load your power company wants and both can be bought this year ( Sept for the Leaf, Nov for the Volt )

    Unfortunately, they now know me by name over at DTE, so I will not be able to pull a fast ball on them and claim I am purchasing an EV this year. I am happy with my 5 KW system size. Any bigger and shading will become more of an issue on my roof anyways.
    autoxsteve wrote: »
    Scott,

    Have you considered Evergreen panels? I am quite pleased with their performance.

    Yup, they were second choice behind Sharp. I agree, it sounds like they have good performance for a great price.
  • newenergy
    newenergy Solar Expert Posts: 291 ✭✭✭✭✭✭
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    The pics look good. Personally, I've argued with people that we go out of our way to put up only aluminum and stainless steel because we want to minimize corrosion for decades, so why put it on galvanized strut? Electricians love strut.

    I'm sure it will be fine, but the strut will probably be kinda rusty in 10 years.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    I used to purchase Zinc based paint (is it still available?). Made whatever was painted look like a hot dipped cyclone fence (i.e., not very pretty)--but no more rust problems right on the California coast (salt air / salt fogs).

    Zinc Paint Report

    The other thing that helped was rust conversion coatings/"washes"... I think it was phosphoric acid + a little soap (good penetration). We have lots of salt spray/fog and this was a great product (leave a light film of rust, then the acid converts to a [FONT=arial, Arial, Helvetica]Iron Phosphate compound which was a good protection... Then paint over with good quality sealer/paints.

    -Bill
    [/FONT]
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SpartanScott
    SpartanScott Solar Expert Posts: 41
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    Thanks for pointing out the galvanized strut.

    I am now working on placement and orientation of the panels. 16 panels will go on my upper roof in a vertical orientation. I've located the remaining 8 on the middle roof, as high and West as possible. My lower, or West-most, roof is not an option do to high amounts of late afternoon/evening shading (see photo).

    I modeled my home and the panels in a 3D modeling program. Here are two snapshots, one which is looking directly North on the home, and the other looking directly NW. Early morning hours will throw some roofline shading on the lower 8 panels. Evening shading from trees will start on the West-most panels and move East until all panels are shaded by the trees.

    I have one theory question regarding which panels to string together. Assume 22/24 panels are in full sun, and 2 panels are shaded. Wouldn't it be better if the two shaded panels are on different strings? That way each string would have the same Vmp (322V in my case) and the inverter would not have trouble finding Pmax. If those 2 shaded panels were on the same string then one string would have Vmp=350V, and the second string would have Vmp=293V.

    Apply that thought to my design, and I would think that for the 8 panels on my middle roof, the upper 4 should be on a different string than the lower 4. Is this the right way of thinking when designing my strings?

    Thanks, Scott
  • Solar Guppy
    Solar Guppy Solar Expert Posts: 1,989 ✭✭✭
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan
    . Wouldn't it be better if the two shaded panels are on different strings? That way each string would have the same Vmp (322V in my case) and the inverter would not have trouble finding Pmax.
    Thanks, Scott

    Yes, much lower losses this way, a bit more wiring
  • newenergy
    newenergy Solar Expert Posts: 291 ✭✭✭✭✭✭
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan
    Yes, much lower losses this way, a bit more wiring

    I don't doubt you, but that's confusing. When you have modules divided over different roof orientations isn't it best to keep each entire string on the same orientation? Is shading different?

    My understanding was that different levels of light produce and allow for different amounts of current through each module and a shaded module will restrict current flow. Two shaded modules would cause the same restriction - so it's better if they are in the same string.
  • solartek
    solartek Solar Expert Posts: 69 ✭✭✭✭
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    I don't see any different orientation between the 2 array locations. Do you?

    Scott. (Solartek, not Spartan :^)
  • newenergy
    newenergy Solar Expert Posts: 291 ✭✭✭✭✭✭
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan
    solartek wrote: »
    I don't see any different orientation between the 2 array locations. Do you?

    Scott. (Solartek, not Spartan :^)

    No, but I was just talking about different light levels on different modules in the array and how you should string them. Seems like different orientation is similar to different shading levels and that strings should either be in the same conditions shading and orientation or they should be mixed with either shading or orientation.
  • Solar Guppy
    Solar Guppy Solar Expert Posts: 1,989 ✭✭✭
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    No, when a panel gets shaded the bypass diodes take over ( all it takes is a single cell in the panel to be shaded ) , so it is better to have in this example the array have panels in both arrays in series. They are at the same angle its just the lower array will gets shading from the higher array / roof in the morning if I understand the photos
  • DC Builders
    DC Builders Registered Users Posts: 13
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    Wouldn't that put you over 600 volts?
  • Solar Guppy
    Solar Guppy Solar Expert Posts: 1,989 ✭✭✭
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    The OP would split the upper and lower arrays, so its the same number of panels in a series string, so no voltage difference. You would have two strings , half from the upper and half from lower arrays in series, times 2 vs. one string all upper and the other all string lower panels.
  • SpartanScott
    SpartanScott Solar Expert Posts: 41
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan
    newenergy wrote: »
    My understanding was that different levels of light produce and allow for different amounts of current through each module and a shaded module will restrict current flow. Two shaded modules would cause the same restriction - so it's better if they are in the same string.

    With bypass diodes and only 2-4 panels in shade, as in my case, you would want shaded panels split evenly between each string. The math does get fuzzy if there is not enough shade for the bypass diodes to kick in, or if more panels are shaded. In the case if 50% of the array was shaded, it may be better to group the shaded panels on one string.
    No, when a panel gets shaded the bypass diodes take over ( all it takes is a single cell in the panel to be shaded ) , so it is better to have in this example the array have panels in both arrays in series. They are at the same angle its just the lower array will gets shading from the higher array / roof in the morning if I understand the photos

    Thank you Solar Guppy for confirming my design. Yes it is the upper roofline that will shade 2 or 4 panels of the lower array in the early morning hours. By the way, anyone know how many bypass diodes are in one Sharp ND224UC1 60 cell solar panel?

    I am still doing 12 panels per string. A string will consist of 4 panels from the lower roof and 8 panels from the upper roof. Max Cold Voc = 526V.
  • solartek
    solartek Solar Expert Posts: 69 ✭✭✭✭
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    For a 60 cell solar module (6x10 cell arrangement) there is most likely 3 bypass diodes: 1 per 20 cells in series.

    Scott.
  • a0128958
    a0128958 Solar Expert Posts: 316 ✭✭✭
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan
    ... full system turn-key price of $6.00/Watt

    ... decided to cut the SMA monitoring (Sunny Webbox) and install a more detailed monitoring system. I have chosen the Web Energy Logger system which will cost around $1000.

    Scott, I have appreciated your efforts to post your progress - further helps the learning process.

    Your $6/W turn key price is what the Dallas market is at too, BTW. And some installers here give you the choice of a central inverter or go with Enphase inverters, with no price difference.

    As you know I have the WEL too. I think your cost is more on the order of $750, not $1000, and this still includes temperature, humidity, counting, on/off control, etc. If you're just starting with power monitoring only, then you're down to $650.

    Feel free to use my examples as input considerations for your design use of the WEL.

    Last week I went ahead and ordered an SMA manufactured $150 accessory communication module that goes into my SB7000, to enable me to occasionally hook up a laptop to the inverter and get DC operating values. This may be an option you may want to consider too to enable understanding / checking the performance of your panels with accurate DC voltage/current values.
    ... anyone know how many bypass diodes are in one Sharp ND224UC1 60 cell solar panel?

    Your panels are just like mine (Astronergy 225 W panels - 60 cells in each panel, arranged in a 6 x 10 matrix). Published detail for my panels says there are 3 bypass diodes per panel, and 20 cells per diode.

    Best wishes for continued excellence and success.

    Best regards,

    Bill
  • SpartanScott
    SpartanScott Solar Expert Posts: 41
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan
    a0128958 wrote: »
    As you know I have the WEL too. I think your cost is more on the order of $750, not $1000, and this still includes temperature, humidity, counting, on/off control, etc. If you're just starting with power monitoring only, then you're down to $650.

    Thanks and congratulations on getting your system up and running this week. I agree, power monitoring can be done for $650 with the WEL. I actually just received my WEL and Wattnode today. I will be logging home energy, PV energy, 12 temperatures, and 4 on/off indicators. Total bills come to $1046; $667 for the WEL and sensors, $323 for Wattnode & 3 CT's, and $56 for wiring etc. I will start installation of it this weekend.

    I'm not too interested in logging PV DC Voltage & Amps as you are going to do. With the SMA inverter I can check DC voltage on the display. You should get more useful information out of it since you have different orientation strings forced to operate at a single voltage.
  • a0128958
    a0128958 Solar Expert Posts: 316 ✭✭✭
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan
    ... I'm not too interested in logging PV DC Voltage & Amps as you are going to do. With the SMA inverter I can check DC voltage on the display. You should get more useful information out of it since you have different orientation strings forced to operate at a single voltage.

    I thought the same, too, that I'd just occasionally get DC values from the display. But, unless your SB5000 display is different than my SB7000, you won't get any DC current or DC power information. I believe you'll have to hook something up to get this info, regardless of desire for real time or logged. At least this is my understanding at the moment.

    My setup I believe will be the minimum to occasionally get DC volts and amps. I'm not planning to do any logging of these values, nor do I know if the interface board I purchased and the free s/w from SMA even provides for logging.

    BTW, once you've got your WEL running, holler if you want help with any questions.

    Best regards,

    Bill
  • SpartanScott
    SpartanScott Solar Expert Posts: 41
    Re: 5 KW Grid-Tie PV Solar System in Mid-Michigan

    Last Friday I signed the contract and paid 55%. A crew came out for a couple hours to take detailed measurements and confirm their ideas with me. As a last minute change I got a no cost upgrade to a SunnyBoy 6000 Watt inverter. I was reluctant to do the upgrade because of losing some low power efficiency. With the SB6000US I will not be capped at 5kW during peak mid-day sun hours.

    Pulling permits has caused some trouble. The township waived my permit, but I do need permits with the city. The city requires full detailed (& stamped) design with structural and site drawings. Neither I nor the city had structural drawings of my home on record, so my installer had to use his measurements to create a set and then have a structural PE review and stamp the design. The permit package will be submitted Monday and then the city requires a 7-10 day review before they will issue the permits.

    I've got a nice set of design drawings now, but am playing the waiting game for the permits. I have rescheduled the installation for March 19th/20th. After some back and forth on the materials list, we made the order of all the equipment two days ago. It will arrive at my house in 2-3 days.

    The past week I've been installing and playing around with my monitoring system. Right now I'm grabbing energy readings from some of my high power appliances, until I get to slip the CT's over the inverter output in 2 weeks! This is my monitoring website:
    Scott's Home Monitoring System