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My Suburban Rooftop Solar

Discussion in 'Energy, Environment, and Policy' started by Skotty, Aug 16, 2017.

  1. Skotty

    Skotty 2014 Model S P85

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    #1 Skotty, Aug 16, 2017
    Last edited: Aug 16, 2017
    Thought I'd provide a few details to interested parties about my rooftop solar installation. Might give others some things to think about for their own houses, or maybe you'll give me something else to think about.

    I'm in the Kansas City, Missouri area. Incentives are not so great here, but I'm doing it more for just supporting clean energy, and in that respect Missouri is a prime candidate, as we have a lot of coal power here and utilities are dragging @$$ on building clean energy capacity.

    I live in an HOA community, so that is an extra hurdle to clear to get solar installed. Here's the steps I've taken, many of which were done largely just to appease the HOA and get approval for solar install.

    1) About a year ago I canvassed the region for solar installers, contacted several, had several come out to the house. This was to get an idea of what it would be like and see what kinds of companies, pitches, products, and prices there would be. I came out of that process feeling really good about 1 installer and not so great about all the others. One topic worth discussing is current status of the roof. You don't want to put solar on a roof that is close to needing replaced.

    2) Several months ago I contacted my HOA to see if they wanted to discuss solar in advance. They gave me some limited info, but generally they were not interested in having a formal discussion. Also reviewed neighborhood covenants, which in my neighborhood has nothing on solar. However, they are picky on other things, like what kind of basketball goals you can put up, so I am expecting some possible resistance.

    3) The last couple of months I searched for information on others in suburban or urban communities that have installed solar, and what kinds of issues they have had. I even contacted one individual personally to discuss his situation.

    4) The last couple of months I reviewed the laws for solar in Missouri. Missouri has a statute saying that solar energy is a property right but it is kind of vague and has more to do with easements. There is at least 1 Missouri state senator who is trying to get a Solar Access Rights bill passed but has been unsuccessful so far (hasn't been voted down, just haven't been able to get it up for vote in the first place). Also reviewed the ITC solar tax credit dates and rules.

    5) Happy with my 1 solar installer, I contacted them a month or so ago to inquire on if they would still be able to install solar for me, and what the process was. One important point about the process is that they have a designer come out to do the initial design work (which includes figuring out electrical and other stuff, part of which is done to be able to get all the necessary paperwork done for the utility, city, etc). Sometime after that a team comes out to actually install everything. Given this approach, I asked if we could do the design separate from the install, and they agreed. The purpose for this was so that I could get the design done, then pause to do the HOA proposal and have it include all the design details, then have the install done after I get HOA approval.

    6) In the last month, I reviewed what loan options would be available to us.

    7) I looked at a few homes that had solar installed. This was helpful because we noticed some differences between installations that would be good to discuss with installer and that the HOA might care about. For example, how the wiring is routed. Saw some houses where it was completely invisible, others were they had blatantly obvious tubes running in highly visible areas that really stuck out like a sore thumb. On one hand, I don't care, but on the other, the HOA will (and neighbors might too).

    8) There was concern in our community about solar panel glare, so I did a little informal but pretty thorough study of what glares solar on my roof could cause, so that could be taken into account in the design. I have a separate thread about that here in this forum.

    9) I discussed some design details over email with my installer. I asked for black framed panels with black installation hardware, and I also asked for at least 2 different layout options. This was in anticipation of needing additional negotiating room and selling points with the HOA. People tend to prefer the look of black framed panels, and I'll have the designer to an optimum functionality panel layout and a second layout that optimizes aesthetics. The second is the back up option if HOA rejects the first on appearance issues. I also asked if they could hide all the wiring/piping, as that can be a thing, and I'm certain it's something the HOA will care about.

    10) Designer coming over this weekend to look over the house. After that, it will be a week or so before he or she has all the work done. I already have money set aside for this work, though the actual install I will get a loan for.

    11) Once we have the design docs back from designer, we will write up the proposal to the HOA. It will include a blurb about what we are doing and why we are doing it. It will discuss design decisions in a way that hopefully helps convince them to approve (like discussing the black framing). It will include information on the glare study. And it will include the full design details from the designer. However, it will include only the preferred layout, making no mention of the other. If they don't approve on aesthetic reasons, we will break out the other layout or layouts in a revised proposal.

    12) Our goal is to get approval sometime this winter. We will then secure a loan and have the actual installation done in the Spring.
     
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  2. Bad Horse

    Bad Horse Member

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    Interested in seeing how this goes, I live on the other side of State Line but live in neighborhood w/o an HOA. I still probably won't get solar until the next door neighbor's giant oak tree finally dies, but still it would be interesting to see the costs and the process of how this goes from someone else locally.
     
  3. Skotty

    Skotty 2014 Model S P85

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    Update: The designer and owner were over last weekend to get all of the information they needed to complete the design docs. After discussing layouts, we decided they would initially just do a single layout plan. I agreed to this on the stipulation that they not increase costs if the HOA rejects something about the layout and they have to revise.
     
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  4. Skotty

    Skotty 2014 Model S P85

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    #4 Skotty, Sep 1, 2017
    Last edited: Sep 1, 2017
    Update: Got the basic design plans back. Submitted proposal to HOA.

    One thing I find tedious about rooftop solar is the lack of quality information. It's extremely hard to find reviews or even honest price and feature comparisons between different solar panels, microinverters, etc. Even finding pictures of solar installations and solar panels is impressively difficult (I got the best pictures by driving around the city and taking my own pictures).

    It's also hard to know what to expect from installers. What should we be expecting them to do or not do? How should they be planning the layout? Should they actually be getting up on the roof and taking measurements (the companies I have considered have not done this -- not even the ones I paid money to)? Do they just figure it out on the fly?

    Many installers tend to give crap answers to questions (non-answers and dodges like politicians sometimes do). I've personally been witness to this, and not just from installers I considered for my own solar install.

    If I were a philanthropist, I would be hiring electrical engineers to start doing some real testing and comparison of different panels from different manufacturers and of related equipment like microinverters and mounting hardware.

    One thing I'm going to do with my install, that not nearly enough other solar customers are doing, is providing a thorough review of all the hardware and software that goes into my system. I'll probably finally use my youtube account again for this, in addition to providing reviews with pictures on the web.
     
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  5. nwdiver

    nwdiver Active Member

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    #5 nwdiver, Sep 1, 2017
    Last edited: Sep 1, 2017
    IIRC FlasherZ is in KC too. He recently installed some solar. Have you hit him up for input yet?

    I've never noticed a significant difference from panel to panel with the exception of SunPower panels. SunPower is definitely the Tesla of the solar panel world. Their cells are all back contact so the modules look very clean, they have large copper connections so they're extremely resilient to thermal cycling and they're mono so they have a very good temperature coefficient. Unfortunately SunPower does to sell to retailers like other manufacturers do and they're expensive... typically ~2x the cost of other panels.

    I don't know how much of a concern cost is for you but if you're looking for a better ROI I would shy away from micros unless you don't want to mount a string inverter. Traditional String inverters run <$0.20/w. Optimized systems like Solar Edge run ~$0.40/w and micros run ~$0.60/w. You pay a heavy premium for micro inverters.... talking to electricians I really think the primary reason for their popularity is that electricians don't have to worry about understanding DC.

    That's what NREL is supposed to do :(
     
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  6. miimura

    miimura Active Member

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    My installer put an instrument on the roof with a spherical camera. It measures the slope of the roof and it takes a picture so that they can calculate the sun position and shading condition by time of year. It came out very accurately in my case.
     
  7. Skotty

    Skotty 2014 Model S P85

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    My solar rooftop proposal was approved by the HOA. Yay!

    As my installer wants to use APSystems microinverters. I asked him to take a look at the new YC600 vs the YC500A (he was planning on using YC500A). Just in case anyone has any comment about that (in particular the YC600 vs YC500A), I thought I would mention it. We are not getting as many panels as I originally wanted, so might be nice to try to get higher capacity inverters and panels, which is why I asked him to look at the new YC600. I think the installer was also looking at using 290W panels. I'm willing to pay for higher wattage ones if it is sufficiently worthwhile.

    While cost is a factor, it's not the primary factor, generating clean energy is, so I'm willing to build a less cost effective system if it can produce more energy.
     
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  8. nwdiver

    nwdiver Active Member

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    I went to a presentation by an installer up here in WA to try to pick up some PRO-tips. I'm still not sold on the micro inverter thing (especially where shading and different angles aren't an issue) but they're really loving their AC modules. They use them almost exclusively and haven't had a single failure.

    If cost isn't an issue have you considered SunPower? They make a 360w module :)
     
  9. Skotty

    Skotty 2014 Model S P85

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    Amazing how hard it is to get a no BS answer to what size panels should be used for a particular inverter. All it would take is data from existing installations.

    What makes it extra hard is every page out there that discusses the matter (none of which seem to provide any hard real data), they focus almost exclusively on maximizing cost benefit, without taking into consideration that some people like me place the value of generation at a higher level of importance than the cost. Cost is still a factor, but not the end all be all factor. If I had some good graphs showing real data of the amount of clipping different combinations experience across different climate zones, I could determine the ideal balance on my own.

    Anyway, assuming we stick with AP Systems microinverters, the choice is between inverters that can handle 250 or 275W per panel. The current default panel choice of the installer is 290W panels, but I could probably get them to install higher wattage panels. At the moment, they only think they can get 20 panels on my roof, which is kind of sad and makes me want to push for higher output at the expensive of lower cost benefit.
     
  10. SageBrush

    SageBrush Active Member

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    I was space limited so I bought the more expensive but higher efficiency LG 315 panels that are ~ 19%.
    Since I have some shading issues I chose SolarEdge DC optimizers instead of AC microinverters. I was not entirely convinced of the reliability of the latter and I also found it difficult to match the microinverter size to the panel. The DC optimizers solved aspects #1 and #3

    Now that I am able to monitor output by panel, I am amazed by how little shade is needed to hobble a panel's output.
     
  11. nwdiver

    nwdiver Active Member

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    You can play around with PV Watts... under the advanced parameters tab there's a DC:AC size ratio.

    What's the reason your installer wants to use micro inverters?
     
  12. Skotty

    Skotty 2014 Model S P85

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    It's what they are comfortable with I guess. In general, I like the panel level data. Then there are power optimizers that another company likes to use. I guess those would be fine too, plus I think they also provide panel level data. But my installer wants to use microinverters, and I don't have a good reason to request otherwise.
     
  13. Skotty

    Skotty 2014 Model S P85

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    Starting to feel a little uneasy about my solar installer. Talks a good game in person, but email responses give me pause. Owner hasn't responded when I asked about how he handles the payment transaction, and whether or not he does a legally binding contract.

    I wish trying to get solar installed wasn't so wild west. It's especially hard to find good installers in the midwest where the energy mix is the most polluting, which is unfortunate. Solar City just says tough luck. Tesla doesn't call when asked for quote. They have no interest in serving the middle of the country right now. Other places I've contacted before seem incredibly unprofessional. The only professional place I've contact so far wanted over $40K for a rooftop system that will probably only be around 6 kW.

    Getting depressed.
     
  14. SageBrush

    SageBrush Active Member

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    #14 SageBrush, Sep 30, 2017
    Last edited: Sep 30, 2017
    Efficiency.

    I've forgotten ... why are you screwing around with installers ?
    DIY. The group I volunteer with puts up PV at ~ $1 a watt, although you may want to spend another 20 cents a watt to get tier 1 panels with a better thermal performance for your summers.
     
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  15. Skotty

    Skotty 2014 Model S P85

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    As for the microinverters, I do kind of want panel level data and for the system to be able to manage things like shading. Based on what I've read, that means either microinverters or power optimizers.

    I'm actually a DIY person in a lot of cases. I often do my own car repairs and home construction projects. In another week or two, I'll be doing all of my attic efficiency work on my own. But I think I know what I don't know, and I don't know electricity all that well. Sure, I can run new wiring for a new 120 outlet, but rooftop solar involves a lot of things I don't feel qualified to do. And just to add an extra reason, being on a roof scares the hell out of me.
     
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  16. SageBrush

    SageBrush Active Member

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    #16 SageBrush, Sep 30, 2017
    Last edited: Sep 30, 2017
    I'm afraid of heights, but I pretty much walk around on roofs without much concern, at least up to a 15 degree pitch.

    I'm pretty sure you are a better DIY'r than I am (that does not take much), and I am a complete bozo when it comes to electricity. Yet I built my PV array with some help with my wife. It is that easy. I did call in a local electrician for the wiring work, as do the homeowners we put up PV for. In my area that is about $500 of the total final cost.

    Optimizers, optimizers, optimizers !!!
    SolarEdge has grabbed close to 50% of the residential market, and I'd say for very good reason. I am delighted with my purchase.

    For panel level monitoring, I used the built-in ethernet card in my inverter and ran an ethernet cable through my garage and into a little wireless access point in the house. Total cost for wire and AP was ~ $40. It did take me a good 30 minutes and a better youtube video before I became competent in adding the connectors to the wire. The trick turned out to be to NOT strip the wires before insertion into the connector. Be sure to get yourself a wire checker.
     
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  17. Park2670

    Park2670 Member

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    I have been taking many of the same steps you have. Decided to go DIY and save myself over $8,000. I decided on Silfab panels, SolarEdge Inverter with Optimizers.

    Had similar experiences with multiple companies here in Utah, and never heard back from Tesla. Found its just going to be worth it for me to learn as I go and save the money.
     
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  18. Skotty

    Skotty 2014 Model S P85

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    I'm tired of doing everything myself because everyone else is either a swindler or incompetent.
     
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  19. nwdiver

    nwdiver Active Member

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    Agreed. While I'm still too cost sensitive to be sold on the idea of paying ~$0.20-$0.40/w for module level monitoring... $0.20/w is A LOT less than $0.40/w...

    I'd really love to see a side-by-side comparison of an optimized system vs string inverter. The last system I installed uses 2 independent MPP trackers. It's interesting to see the performance difference. The current difference between the trackers is <0.1% so from an efficiency perspective there would be very little to gain from optimization.

    The new SMA residential inverters now have 3 MPP trackers. Since each string can be on it's own tracker partial shading of one panel will now only affect one string... and even that would be minimal. Likely to the same extent as if they were optimized due to the bypass diodes. I'm also a huge fan of the new line of SMA inverters because of the Secure Power Supply system they offer. In light of what's happening in PR; as an installer; it almost feels like negligence to sell systems that are useless w/o the grid....

    I dunno... I agree that module level monitoring is cool... but I've never seen a panel fail. I know installers that have put up ~4MW and have never seen a panel fail... For a 10kW system I have a hard time justifying $2k-$4k for module level monitoring....
     
  20. SageBrush

    SageBrush Active Member

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    #20 SageBrush, Sep 30, 2017
    Last edited: Sep 30, 2017
    Perhaps because I am able to see each panel, I've been amazed how little shade it takes to drop panel output to 20% of PTC. I'd hate to think of my entire string going down to those levels from that same shade spot.

    On the other hand, clouds in the sky do not have anywhere near the same effect so the benefit of optimizers is a very site dependent phenomenon. This photo shows a panel operating at the above mentioned reduced rating. For those wondering -- apparently the 3 diodes in a panel split the panel vertically. The photo is over-exposed to highlight the shade from a pine tree offset about 10 feet. The panels are black.

    Shade.jpg
     
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