Renewables: "talking 'bout my generation"

tunnel

jevban wrote: »

Hi all, as Martyn knows, I am having problems with my system...I have 3 rooves with a dual mppt 4kw. After much argument and involving of the regulators, the company are offering me the following options...put my 2 sw/we panels,4 on each roof, onto a dual mppt 3kw ..leave my nw panels where they are and put them on a separate 2 kW inverter. Or use micro inverters. What do peeps think please? I need to make a decision ..the owner thinks this will resolve problems as he disagrees that I have shading and won't commit to brands such as solar edge or enphase. Advice please.

Jan

Are you saying he's offering a second inverter? Would this then make each roof on a separate string?

jevban

Yes....Dual mppt for the 2 south ish facing rooves and single inverter for nw roof..all will be separated.

tunnel

I have actually been reading your other thread and just seen the pictures(google earth) of the layout. I'm assuming you have shading in a morning on the SW roof from the chimney? I don't know much about micro inverters but if they allow each panel to work independent like Solar Edge PO's then I'd say that'll probably be your best bet. I would take advice from the other forum though as there is quite a few installers on there and they do know what the hell they're talking about

legoman62

0.975 O's today:D Friday not looking good tho:(

jevban

Hi Tunnel

Can't say shading on the roof has ever been a thing I have ever taken notice of before now..I think I will always have a less than perfect install as my hipped rooves don't really lend themselves to such a thing...I just need to come to a decision. The independent guy who appraised the system today is on the net to me and is saying the panels and their sizes are crucial to a good design,but 2 inverters will work..he suggested optimisers,but the MD is saying he will not direct this as I need to make the decision. Dilemma

tunnel

IF you can have 2 inverters, one for the SE/SW with 2 strings and the other solely for the NW then I'd probably say that's the best of a bad situation, at least each roof will work independent and not be dragged down by another.


If you look at my signature you'll see I have 3 systems, each work from their own inverter, but then each was installed separately.

jevban

Hi Tunnel and thanks ...I did look at your signature and wondered..I've been looking through a number of postings looking for differing arrays...the calculations on PV Gis were posted by a chap on the other forum for the 3 rooves and I can live with generation of 900+ for the nw side its just trying to get it to work...calculations coming in vary between 2700 and 3170.. The owner still says he stands by his calculations and Marty has said if I get around the 3000 mark, then that's a result. We do have great sun to the rear of the house as although the sunrises to the front of my house in the morning it is sunny and bright in the afternoon..I am never going to have the results s facing houses have...that's been my niggle all along...if he had been upfront,I would not have taken the system...however,I have it now and he will not refund, so its make the best of it I can. What was picked up today was one of the DC switches was turned off !

Thanks for the thoughts

Jan x

tunnel

Jan,


As has been stated on the other forum, your system is too big with 14 x 307 panels to qualify for the 14.9p rate. If you are going to "lose" a panel might I suggest you remove one from the SSE roof at the back(the one closest the house). You do have some serious shading issues which(sorry) would best be addressed with the use of a Solar Edge inverter. I know, I've had one retro fitted to my SSW single storey garage system that suffers with shade from my neighbours house. I have already noticed a difference in the performance.


Maybe suggest to the MD that you'll go away quietly if he sets the SSE and WSW on a SE with PO's and the NNW on its own inverter


I know its not the best of advice but then again its not the best of situations...sorry

jevban

Sorry Tunnel

All those abbreviations at the end went over my head! No got it now ! He won't agree to solar edge,but spoke of other optimisers/microinverters...what are the shading issues????

tunnel

Jan,


Your shading issue will be from the main house onto the single storey extension, mostly in a morning. It has been pointed out to you on the other forum, a possible loss of 30-40% on that roof If I remember correctly(sorry I've slept since I read it)