Large Panels on roof

[haythorn_1]

Currently researching whether it’s worth it to put solar panels on the roof on my house whilst we extend and re tile it.

 

The height of the roof from the ridge to the rafter is ~3.6m so I don’t think I have space to put 2 rows of the most common size panels which seem to be about 1700mm tall.

 

Is there any reason why I can’t install the larger panels that are available which seem to be ~2300mm tall so would fit better. These seem to be mainly focussed on commercial installations.

 

example:

 

https://www.powerland.co.uk/products/aiko-comet-1n-625w-n-type-abc-72-cell-silver-frame-gen-2

 

[JohnMo]

You need to ensure the inverter is ok, big panel can mean big amps. Generally hybrid inverters are ok. But check.

[G and J]

1 hour ago, haythorn_1 said:

Currently researching whether it’s worth it to put solar panels on the roof on my house whilst we extend and re tile it.

 

The height of the roof from the ridge to the rafter is ~3.6m so I don’t think I have space to put 2 rows of the most common size panels which seem to be about 1700mm tall.

 

Is there any reason why I can’t install the larger panels that are available which seem to be ~2300mm tall so would fit better. These seem to be mainly focussed on commercial installations.

 

example:

 

https://www.powerland.co.uk/products/aiko-comet-1n-625w-n-type-abc-72-cell-silver-frame-gen-2

 

Interesting.  We are in the process of our MCS solar dude working out if we can fit 2 rows.  If not, as long as these can go flush (sounding unlikely if they are targeted on commercial buildings) then maybe this will be an option.

[Conor]

Three panels in landscape instead, ~3m

[haythorn_1]

7 minutes ago, Conor said:

Three panels in landscape instead, ~3m

Good point! That actually might be better. 
 

Foolish I didn’t think of that!

[haythorn_1]

29 minutes ago, G and J said:

Interesting.  We are in the process of our MCS solar dude working out if we can fit 2 rows.  If not, as long as these can go flush (sounding unlikely if they are targeted on commercial buildings) then maybe this will be an option.

What do you mean by flush? GSE don’t make in roof mounting options large enough so would have to be on rails.

[haythorn_1]

1 hour ago, Conor said:

Three panels in landscape instead, ~3m

Although my preference would be for in-roof panels and it doesn’t seem as though all the GSE landscape modules only work with panels that are max 1120mm in height. Yet all the panels I can find are 1134mm.

 

Does seem a minefield getting everything to fit together!

[JohnMo]

4 hours ago, haythorn_1 said:

ridge to the rafter is ~3.6m

So do two/three rows of normal size panels with GSE or similar mounts in landscape instead of portrait? As suggested above. Big panels aren't always the correct answer.

[Conor]

4 hours ago, haythorn_1 said:

Good point! That actually might be better. 
 

Foolish I didn’t think of that!

I went landscape as had similar constraints. Remember, for GSE trays, you can run right from the ridge to the gutter. You don't need any slates.

 

You'll never get the perfect amount in as you're trying to fit panels in to a roof, not designing a roof around panels. Some is better than none.

[Nickfromwales]

19 minutes ago, Conor said:

you can run right from the ridge to the gutter

Beware, that the rain runoff when torrential may shoot down the panels and run off over the gutter. My PV guy kerbed my enthusiasm on this and explained why, and I get it. An apron course (2 of) will allow the rain to be managed vs the elevated surface it would otherwise be running off. 

[G and J]

31 minutes ago, Nickfromwales said:

Beware, that the rain runoff when torrential may shoot down the panels and run off over the gutter. My PV guy kerbed my enthusiasm on this and explained why, and I get it. An apron course (2 of) will allow the rain to be managed vs the elevated surface it would otherwise be running off. 

Very good point.  Ta. 

[Nickfromwales]

2 minutes ago, G and J said:

Very good point.  Ta. 

Look into deeper gutters, as like everything else in life "it can be done", just best to know what you don't know, before committing  

[G and J]

3 minutes ago, Nickfromwales said:

Look into deeper gutters, as like everything else in life "it can be done", just best to know what you don't know, before committing  

Will do, though there are differing views in our household regarding the aesthetics of panels to the gutters. 
 

If we went for it we could have 18 standard panels in portrait. Just under 8kW

[Nickfromwales]

12 hours ago, G and J said:

Will do, though there are differing views in our household regarding the aesthetics of panels to the gutters. 
 

If we went for it we could have 18 standard panels in portrait. Just under 8kW

That’s a lot of juice, so would good in winter. 
 

Too many people get hung up on how a roof will look, and then very rarely ever look at it again after moving in (when actual life goes on, after the build is no longer all they think about). 

[JohnMo]

1 hour ago, Nickfromwales said:

then very rarely ever look at it again

That is so true of a lot of house related things.

 

14 hours ago, G and J said:

Just under 8kW

We have just had 2 days where all the heating and DHW has been provided by excess PV. We are a lot further north and have plenty of trees so a shorter than expected solar day length. And we have a little over 6kW. Not really done the cost benefit analysis of heating v export. But with heat pump running at an elevated flow temp, we are getting a CoP of 4.8, so turning 5.5kWh PV into 26kWh heat and immersion has cylinder at 70 degs.

 

So 8kW on a sunny February day you will have plenty of export as well. 

[SteamyTea]

You need to check how much you can connect to the grid.

 

[Nickfromwales]

5 hours ago, SteamyTea said:

You need to check how much you can connect to the grid.

 

Or just fit a hybrid inverter, or go for one that supports export limitation.

 

Loads of ways to skin that cat.

[Mattg4321]

21 hours ago, Nickfromwales said:

Beware, that the rain runoff when torrential may shoot down the panels and run off over the gutter. My PV guy kerbed my enthusiasm on this and explained why, and I get it. An apron course (2 of) will allow the rain to be managed vs the elevated surface it would otherwise be running off. 

 

Could you explain ‘elevated surface’. Do you mean panels on rails rather than GSE in roof system?

[Nickfromwales]

2 hours ago, Mattg4321 said:

 

Could you explain ‘elevated surface’. Do you mean panels on rails rather than GSE in roof system?

Yes, sorry, just been typing to fast lately lol. The panels are "thicker" than most roof coverings so the upper surface that the rain is running down / off is higher than say a slate or tile. There have been instances where regular guttering cannot cope with / contain heavy rain water runoff, and that has ended up 'jumping' the gutter and becoming a nuisance.

 

edited to clarify, yes, I mean even with in-roof.

Edited February 26 by Nickfromwales
beer

[G and J]

7 hours ago, SteamyTea said:

You need to check how much you can connect to the grid.

 

We can export up to 5kW without further infrastructure charges, I have been informed.  

 

8 hours ago, JohnMo said:

That is so true of a lot of house related things.

I dread to think about how many issues are preventing sleep right now only to prove to be immaterial to our future happiness.   Only they won’t prove anything as we'll never notice said item and hence never think about it. 
 

8 hours ago, JohnMo said:

We have just had 2 days where all the heating and DHW has been provided by excess PV. We are a lot further north and have plenty of trees so a shorter than expected solar day length. And we have a little over 6kW. Not really done the cost benefit analysis of heating v export. But with heat pump running at an elevated flow temp, we are getting a CoP of 4.8, so turning 5.5kWh PV into 26kWh heat and immersion has cylinder at 70 degs.

 

So 8kW on a sunny February day you will have plenty of export as well. 

And that is EXACTLY where I want us to be.  In my mind it’s not about peak generation, it’s about increasing the number of useful solar days, especially as the panel cost is partly offset by tile saving. 

[Nickfromwales]

26 minutes ago, G and J said:

I dread to think about how many issues are preventing sleep right now only to prove to be immaterial to our future happiness.   Only they won’t prove anything as we'll never notice said item and hence never think about it. 
 

Let me post you some soothing ales, drink these in moderation and you shall sleep like a baby.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Or you'll sell them on to fund the purchase of more airtightness tape, and quietly keep on rocking yourself to sleep.

[Mattg4321]

8 hours ago, Nickfromwales said:

Yes, sorry, just been typing to fast lately lol. The panels are "thicker" than most roof coverings so the upper surface that the rain is running down / off is higher than say a slate or tile. There have been instances where regular guttering cannot cope with / contain heavy rain water runoff, and that has ended up 'jumping' the gutter and becoming a nuisance.

 

edited to clarify, yes, I mean even with in-roof.

That’s not the case with mine. The panels sit a fraction lower than the tiles (which unfortunately are concrete Marley Moderns). I don’t take issue with you saying it’s a problem on some though. 

[Nickfromwales]

4 hours ago, Mattg4321 said:

That’s not the case with mine. The panels sit a fraction lower than the tiles (which unfortunately are concrete Marley Moderns). I don’t take issue with you saying it’s a problem on some though. 

Do yours not have the apron course at the bottom?

 

Assume you’re double battened to get panels lower than the roof covering?

 

Any pics?

[Mattg4321]

7 hours ago, Nickfromwales said:

Do yours not have the apron course at the bottom?

 

Assume you’re double battened to get panels lower than the roof covering?

 

Any pics?

Not double battened. The panels sit directly on the battens, as do the tiles, so not sure why the panels would be higher?

 

 

[Nickfromwales]

1 hour ago, Mattg4321 said:

Not double battened. The panels sit directly on the battens, as do the tiles, so not sure why the panels would be higher?

 

 

No trays? MCS certified?