advise on grid tie system

bobneeds solar adv
bobneeds solar adv Registered Users Posts: 3
in Solar Beginners Corner #1
I plan to put in a grid tie solar system at my house. I have got a bid from renvu on 20 solarworld 250w panel 20 m215 enphase micro inverters a envoy montering system and a s5 mounting system with a few other odds and ends to complete the whole system. they quoted $10,700. Today I talked to solar edge and he said that is old technology and he recommended his power optimizer with single phase inverters and 290w triex u=series panels for about $11,700. can any one give me advise on the pros and cons of these systems.
· Share on Twitter

Comments

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #2
    Re: advise on grid tie system

    Welcome to the forum.

    Well I can tell you that Enphase is not "old technology" at all and does work very well. Many users of their system on the forum, all quite happy with the equipment and performance.

    Never heard of "power optimizer" inverter. Sounds like those V-match units put on each panel to keep the Voltage even with varying insolation to feed a central inverter. Central inverters are the "old technology" and there's nothing wrong with them either.

    Big question: how's the insolation? If the whole array will point in the same direction with no shading issues then it's 50/50 on performance really.

    The Enphase proposal is 5kW array and 4.3 kW inverter. Really could use larger panels on the 215's. Cost of $10,700 is $2.49 per Watt.

    The Solar Edge proposal you haven't given enough details on to determine how much power it can produce, but it is more expensive.

    Details are important.
    · Share on Twitter
  • KozmoK
    KozmoK Solar Expert Posts: 42 ✭
    #3
    Re: advise on grid tie system

    That's not a bad price! I have 27 250w Panels using SolarEdge (using p300 optimizers) and a SE6000. I paid roughly $16,000 for it, installed on a tile rooftop. I am adding another 7 (240w) panels on Monday to max out my production on the SE6000 Inverter- as my roof is angled East/West.

    The SE6000 Inverter has a built in Ethernet connection so it communicates with the solaredge monitoring website (free). Enphase requires a seperate $500 interface.

    I chose SolarEdge over the Enphase because I was afraid in the Arizona Heat my rooftop would boil the electronics in the enphase microinverter. While they are covered under warranty, it takes someone called out to take it off, and return it, and re-install it.

    Your probably asking yourself, wouldnt the SolarEdge Optimizer have the same problem? I have read that the SE opt's have few components that could fail, no electrolytic caps. This unbiased article helped me decide - I dont want to leave any links here, but if you google "enphase-vs-solaredge-picking-the-right-tools-for-the-job" read that.

    Koz
    · Share on Twitter
  • BB.
    BB. Super Moderators, Administrators Posts: 33,590 admin
    #4
    Re: advise on grid tie system

    Is this the link Koz?

    http://ussolarinstitute.com/enphase-vs-solaredge-picking-the-right-tools-for-the-job/

    Posting links to information being discussed is never an issue.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
    · Share on Twitter
  • bobneeds solar adv
    bobneeds solar adv Registered Users Posts: 3
    #5
    Re: advise on grid tie system

    this is a 5kw system. the way he described the system this inverter is like a micro inverter. He is going to send me a proposal and I can get more specific then as for my location I am putting it on my shop over hang which is made of red iron and the roof is metal r-panels. I have been observing the site and seem to have sun from about 9am to about 330 or 400pm. the shop sits on the north side of my property so it gets south sun. As for your avatar I am a retired biologist and actually worked on the ivory billed woodpecker recovery team in Arkansas but that is another story.
    · Share on Twitter
  • KozmoK
    KozmoK Solar Expert Posts: 42 ✭
    #6
    Re: advise on grid tie system

    BB. Yes that was it :)
    · Share on Twitter
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #7
    Re: advise on grid tie system
    bobneeds solar adv wrote: »
    this is a 5kw system. the way he described the system this inverter is like a micro inverter. He is going to send me a proposal and I can get more specific then as for my location I am putting it on my shop over hang which is made of red iron and the roof is metal r-panels. I have been observing the site and seem to have sun from about 9am to about 330 or 400pm. the shop sits on the north side of my property so it gets south sun. As for your avatar I am a retired biologist and actually worked on the ivory billed woodpecker recovery team in Arkansas but that is another story.

    Same 5kW in array, but what is the inverter rating?

    The system apparently works as I suspected with a module per panel adjusting the V output of the panel to match the others so the effect of shading is only a drop in I corresponding. If the array is in full exposure there is no issue with this, and these modules would be unnecessary. You could probably do a straight central inverter system for less money.

    My avatar, by the way, is a Pileated Woodpecker. The picture was taken at the cabin here one Summer. :D
    · Share on Twitter
  • bobneeds solar adv
    bobneeds solar adv Registered Users Posts: 3
    #8
    Re: advise on grid tie system

    I may have posted this twice. I have trees so in the fall there will be some leaves that will shade the site from time to time, some do you think this would justify the additional cost. Thanks for the article.
    · Share on Twitter
  • BB.
    BB. Super Moderators, Administrators Posts: 33,590 admin
    #9
    Re: advise on grid tie system

    One advantage of a micro-inverter system is that production is only cut by the panels covered.

    If you have a string inverter system, if you cover one to two panels on a single string, that entire string's output could be lost while shaded (if two parallel strings, then 50% of system output is lost).

    In the end, solar panels only work well when exposed to 100% sunlight with no shading. If you are looking at 4pm shading when your system is outputting 20% of its rated output, then 1/2 of that is only a 10% absolute of rated loss--Not the whole 5kW noontime output.

    There are lots of discussions on which is better--And with my luck, the one I recommend will be the one that leaves you worse off (poor partial shade vs a couple of early death micro inverters vs a early central inverter death).

    In the end, there is still a lot of churn in the solar industry--10-20 year warranties are barely worth the paper they are written on. I had both a GT inverter and an array fail. The GT inverter was technically already out of warranty and was replaced. The array was in warranty, but the mfg. (BP Solar) has exited the business--I do not know my warranty status (however, I bought the original array at $5.00 per Watt with California Rebates--A replacement array is around $0.50-$1.00 per watt+installation on a 2nd story roof--So not near as bad vs the original costs).

    And in 10-20 years, my GT system will be under a new rate plan (most likely), and the savings will probably be much less (higher fixed monthly charges, lower per kWH rates is my guess).

    In the end--Conservation is usually your best/first place to "invest" your money. GT solar can save you money (depending on the political winds)--But I would not call it an "investment" just like going to a casino is not really an investment either.

    I did it because I did not trust California and the State PUC--So far, it has worked out OK for me. But future returns are not guaranteed.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
    · Share on Twitter
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    #10
    Re: advise on grid tie system

    here is a thread started by an employee(?) of SolarEdge if you did not see it yet

    http://forum.solar-electric.com/showthread.php?6638-Solar-Edge-from-help-me-design-the-most-efficient-system&highlight=Solaredge

    hth
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
    · Share on Twitter

Categories