Solar PV, Where Do I Start, HELP!!!

A question about : Solar PV, Where Do I Start, HELP!!!

Hi all...

We're looking into getting solar PV's but haven't a clue where to start.

(A short story).....

We face 10 degrees from south, but have always been turned down in the past for even RaR schemes. Maybe it's because we have a window in the roof for the loft room.

I spotted an ad in a magazine for a 'simulation to try before you buy via Panasonic.' Therefore I replied to it and a rep came last week to give us a quote. Ј4365 for 6 panels, and so left it at that to think about it.

Now, OH is getting a lease car through her work (NHS), and it's going to be the Mitsi' Outlander PHEV. So we wanted a charge point fitted. Applied for that, and the rep, which turned out to be the MD of the company that's going to do the install, also said they did solar PV.

After doing his survey for the charge point, he gave a 'rough' quote on what he could do as he was running late...

16 panels! (6 or 7 on the south side around loft window, and the others on the east side) for around Ј6/7K.

He's coming over again (proper appointment) to quote properly.

But we're totally lost now because of the first rep NOT mentioning using the east roof.

Please help.....

Best answers:

• Here goes then...
  Our location is NE23 6..
  We have no shading on the south roof, but if you looked down the ESE roof 'hip', there's a tree.
  It's not a huge one, it's away from the house, half way down the front drive, and looking out of the stair window (east side), it'll be about a quarter way high up the roof.
  I may look into having it taken down if possible. It's cracking my drive.
  Or have the crown trimmed, as it's now grown up to and around our phone cable.
  We have a porch with joining garage, so is there a possibility of using that for panels, of is it too low, i.e. the tree when in full leaf??
  We're the last house in a row, and the house next door (east side), starts to curve away from us around a crescent. Will that affect panel performance? The charge point guy says it shouldn't - you can get 'reflected' light from neighbouring buildings...??
  Just had a faff with that PV potential web site...
  It say's (I hope / think), I 'could' generate 3250kwh per year.
  Just one last thing....
  What's all this talk of mini / micro inverters, strings, MPPT etc??
  Confused there, and don't want to be sucked in if the quoting guys start talking about them demanding I MUST HAVE X Y AND Z FOR MY SYSTEM!!!
• Whoops...
  Forgot to say, it's a Velux type loft window, only on the south roof too, it's about a meter square too.
• Right...tree, if you can top it to stop shading then you're going to save money when buying a system. If you don't touch the tree then that's when micro inverters come in, you would need one under each panel and in effect it allows each panel to work independent.
  If you can top the tree then an inverter with 2 strings(duel MPPT is the official name), doing this takes away the need for micros, then each array(S/ESE) will work as one,ESE being one string and S the other...this is the cheaper option too, plus there's less pieces of kit up on your roof that could go wrong.
  Charge point guy should stick to charge point installing(nuff said)
  Velux window is fine BUT in summer if its open and shade part of 1 panel in a string it may bring all the panels down to that ones level, in effect instead of generating say 2kWh it may be 200Wh instead(hope you get that)
  As for location, nearest town would probably be better, there's some installers that do large areas and some folk may not know you area but their installer may still cover it
  HTH
  Ps, keep asking and someone will give you an answer to help
• Cramlington, Northumberland is our nearest town.
  As for the window...
  We've NEVER used it... The two rooms up there have been a storage *cough* junk area.
  But we may be making use of it soon as I'm chipping away at tidying it and improving the insulation (that's another story ).
  When we come to use the room, the window will be on a child safety catch anyway, so will that not then affect the panels performance??
  The charge point guy has a web site that says they do solar PV as well as the charging points etc....
  And as for the tree, you've got me thinking now....
• Thin out the crown it is then....
• Hiya Goldfinger, I'm back just to agree with Tunnel again. If shading can be managed, then don't go with micro-inverters or power optimisers. We both have them on one system each, they work brilliantly, and do their job very well - but if you remove their job (shade mitigation) then that's better still.
  I think you've already resolved your Velux issue, but I have the same, a large(ish) velux on the ESE. I'll attach a photo so you can see that the panels sit quite a bit higher, so as long as you don't open the window wide (just open the vent, or crack the window 2 inchs or so, then you'll be fine. Open it wide and it will cause shading.
  https://www.dropbox.com/s/70ljo8yvmh..._1290.JPG?dl=0
  You can put panels on lower roofs, see my 'ickle' ESE system of 5 panels, 2 as a canopy, but that's a back garden, so consider any pointless, mindless, drunken abuse they could get on the front of a property.
  If the tree is smallish, and a reasonable distance, then shading will be small, and at times of the year when generation is poor, but it will definitely cause a bit of shading. Remember, in the late Autumn to early Spring, the sun is rising in the SE (NE in summer), so is effectively much lower.
  Not the end of the world, I have a large Magnolia at the bottom of my ESE garden, and a house behind that, plus (from the photo) you'll see that the chimney is to the south of my ESE panels, and (yet more) the upper roof starts to shade the lower roof as the sun moves into the SSW ....... yet my ESE systems are somehow still hitting the PVGIS targets I looked up 4 years ago, I'd assumed I'd only get about 80%.
  I (very quickly) stuck a pin in your approx postcode, and just slapped those rough numbers you gave into PVGIS and got 1,890 + 1,460 = 3,350kWh so I suspect you got it right. Well done.
  Strings and MPPT's - a largish system of 16 panels will almost certainly be split into two strings, with 8 panels on each string, feeding into a single MPPT (maximium power point tracker). But the two strings have to be equal (same number of panels, orientation, pitch etc etc). So when you have a 'split system' across two roofs, the inverter needs to be a little cleverer and have dual MPPT's, with one MPPT servicing one set of panels, and the other serving the other set. That way they effectively operate as two separate systems, getting the best out of both, but you only need one inverter. You don't really need to know much about this, apart from confirming you will get a dual MPPT inverter, and also not being confused by any installer jargon. Dual MPPT's are very common, and only cost a little bit more, nothing to be concerned about.
  Anyways, sounds like you're keen, keep going.
  Mart.
• This is, I hope a better 'picture' of our location...
  https://goo.gl/maps/tn3FL
  I see it's an old image... The red car in the front garden went years ago!!!!
  It's so you can see the layout of where the tree is, and next doors house etc....
  Keen? Yes, but don't want to get ripped etc with unnecessary stuff up there!
• What hours does your missus work? To benefit the car charge it will have to be parked up 9am to 5pm summer time. This time of year from 10am to 3pm and that's on a good day. Really only worth the electricity they make from March to Sept. IMHO only worth it for the FIT.
  You also seem fixated on the number of panels quoted. That is wholly irrelevant it is the capacity that is key.
• Not at all there is a big difference to 6x 200kw panels to 6x250 . As i said it is the capacity overall that counts.
  I have 18 panels but that means nothing without telling you that they are 200 ones so a peak of 3.6.
  Been in for 4 yrs know and make about 3100 kwh per year. SW scotland facing ESE
• Hope this shows a better description of our roof...
  We both work through the day, and I think / hope she may only need to charge the car at the weekend as her mileage is so low and near enough within the hybrids electric range..
  As for panels... With us both working through the day, I'm guessing the FIT is a major factor for us now?
• Just been recommended these people, as they did the mums house of a mate....
  https://www.greenenergygeneration.co.uk/index.php
  Anyone else had any dealings with, or know anything about them either....?
• ^^^ Just rang them...
  They use a Swiss made 'REC' panels, and they use they use Solar Edge Inverters with the 'power optimisers'....??