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

Goldfinger09

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. £4365 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 £6/7K.


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.....

tunnel

Goldfinger09 wrote: »

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. £4365 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 £6/7K.


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.....

To coin a phrase "Just when you thought it was safe to go back in the water". WOW £4365 for a whole 6 panels...lol...tell the first one to shove that where the sun don't shine, that there is a cowboy in disguise!!


First, is the window a velux? or dormer style?
Second, the second quote is still too much, even for a dual aspect roof, get some more quotes..hopefully around the £5-£5500 mark(4kWp system),
Third, Come back on here and post your quotes and kit offered. There's plenty of folk on here that'll run an eye over them and let you know if you're in the right ball park
Fourth, Do you have any shading on both rooves(important to do with question 1)
Fifth, East facing roof is perfectly fine, it will make about 80% of that of a south facing roof
Sixth, Post your rough location and other members may be able to recommend an installer close to you


Please don't be daunted, as I said there's plenty of help on here, no-one here wants to see people getting ripped off(like your first quote)


Tunnel

Martyn1981

Goldfinger09 wrote: »

Hi all...

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

Please help.....

Hiya Goldfinger. Just to confirm everything Tunnel said. If you can get a dual system (E+S) for £5,500, I'd reckon that's a good set up and deal, so 'enjoy' the appointment and learn as much as you can, then get some more quotes.

Do some homework before the appointment, have a read of the PV FAQ's. We (bunch of MSE PV'ers, not installers) put these together as general advice.

Read sections 1 & 2, then maybe have a quick play with section 5 so you have an idea of potential generation, and income. As you're considering a dual system you will have to do it twice, eg 6 panels 1.5kWp south (azimuth zero), and 10 panels 2.5kWp east (azimuth -90). Try to be as accurate as possible so amend by the 10d you mentioned.

Of course you're lost, 4 years ago I didn't have a clue, but just take your time and check anything out that you're not sure about, there are always folk on here happy to chat and explain all the ins and outs.

Mart.

Goldfinger09

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. :mad:


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!!!

Goldfinger09

Whoops...


Forgot to say, it's a Velux type loft window, only on the south roof too, it's about a meter square too.

tunnel

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

Goldfinger09

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 :mad: ).


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....

tunnel

Goldfinger09 wrote: »

The charge point guy has a web site that says they do solar PV as well as the charging points etc....

Next he'll be advising you to position some mirrors for optimum exposure. All panels will generate something while the sun is up and not directly on the panels(unless covered in snow or thick fog/cloud). That's the first time I've heard of houses bouncing the rays...lol


Ps, lose the tree and lose £500 off the purchase price(no need for micros or solaredge)

Goldfinger09

Thin out the crown it is then....

Martyn1981

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/70ljo8yvmha5ioj/IMG_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.

Goldfinger09

This is, I hope a better 'picture' of our location...


http://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!