Solar PV Quote seems excessive

groovyf

I've just had my panels installed - it took 2 guys about 8 hours to get those on the sides of the roof - and help with cabling, (whilst the electrician was busy doing his own stuff), so about 16 man hours.
Your quote has 28 man hours - that may be where some of the extra cost is involved? Over-estimated?
What is the average install time?

Ageing_Stick_Insect

Groovyf,

How many panels did you have installed? Mine will have 28 which is probably more time-consuming but you're right, it could be a wild estimate adding to the cost.

I've written to my quoting company breaking down the panel and inverter cost asking about the £2,400 difference. A reasonably profit I accept but that seems ridiculous especially as they can buy at trade.

Martyn1981

Ageing_Stick_Insect wrote: »

Hi Martin,

But if I can get around £2K off I might go for it without other quotes because those triangular panels look ideal to maximise solar capture.

Hiya Ray, as mentioned, completely unaware of those panels till last week, but have to say I'm quite taken by them.

Personally I quite like the look of PV, it's a bit like putting a picture on a plain wall. Others think 'the picture' spoils the wall, fair enough. So I don't mind too much the look of rectangles on a triangular hipped roof ...... but ...... have to admit, those triangles do look nicer.

I'd guess for the same money, you could put 20 regular panels (5kWp) across the 3 rooves. Mind says "maximise generation", heart says "sexy triangles".

Ageing_Stick_Insect wrote: »

Gents,

Is a panel controller the same as a panel optimiser?

Almost certainly they are referring to PO's (power optimisers) and the quote must be including them. They cost about £40 each retail +VAT and can be found on page 2 of the SolarEdge inverter section on that site:

http://www.swithenbanks.co.uk/shop.php?page=2&c1=Solar%20Photovoltaic%20Equipment&c2=Grid%20Tie%20Inverters&c3=SolarEdge&sp=1

For info on (SE) SolarEdge, if you haven't already, check out their 3 part YouTube videos, which explain it well in about 10 mins:

https://www.youtube.com/watch?v=lsa9rHpDVmQ

I've got a SE system on my WNW roof, as there is a lot of variable shading. It's also ideal for mixing lots of different panels, orientations, pitches etc through to a single inverter. Their inverters are very efficient (~98%) and have long standard warranties (12 years). On top of that, as standard you get a top rate monitoring system that lets you know how each individual panel is performing, but I'm slowly weaning myself off that particular addiction!

Mart.

tunnel

Martyn1981 wrote: »

Mind says "maximise generation", heart says "sexy triangles".

Mart.

You really do need to get out more :rotfl::rotfl::rotfl:

Ageing_Stick_Insect

Martyn1981 wrote: »

Hiya Ray, as mentioned, completely unaware of those panels till last week, but have to say I'm quite taken by them.

Personally I quite like the look of PV, it's a bit like putting a picture on a plain wall. Others think 'the picture' spoils the wall, fair enough. So I don't mind too much the look of rectangles on a triangular hipped roof ...... but ...... have to admit, those triangles do look nicer.

I also like the look of them and they offer the best of both worlds.

I'd guess for the same money, you could put 20 regular panels (5kWp) across the 3 rooves. Mind says "maximise generation", heart says "sexy triangles".

I'm reluctant to put any on the WNW roof as it won't get anything for 3-4 months per year.

Almost certainly they are referring to PO's (power optimisers) and the quote must be including them. They cost about £40 each retail +VAT and can be found on page 2 of the SolarEdge inverter section on that site:

Thanks for the link. That adds another £1000 to the cost so it is becoming clear why this quote is higher than average.

For info on (SE) SolarEdge, if you haven't already, check out their 3 part YouTube videos, which explain it well in about 10 mins:

Will do, thanks.

I've got a SE system on my WNW roof, as there is a lot of variable shading. It's also ideal for mixing lots of different panels, orientations, pitches etc through to a single inverter. Their inverters are very efficient (~98%) and have long standard warranties (12 years). On top of that, as standard you get a top rate monitoring system that lets you know how each individual panel is performing, but I'm slowly weaning myself off that particular addiction!

Mart.

Is yours a hip roof or gable-end? I can understand if you have a gable end as you can fit lots of panels on it but mine is not so good. And adding more of those triangular panels will push the cost up even more. I'm fortunate in that there is little or no shading on the roof. Next door's roof is sufficiently far away not to impact providing the panels aren't right at the bottom of the roof. And there are no trees that could cause shading.

I don't mind paying for quality monitoring software as that will allow me to make sure I get the best out of the system. I'm sure it does become addictive and I expect I'll be sat there watching the numbers for quite a while.

tunnel

I understand the reluctance to consider panels on a WNW roof...however, I have 2.5kWp of panels on mine and I'm averaging around 3kWh a day generation at the mo. Its really nice when I see my SSW dropping to 40-50W gen and the WNW is banging 5-600w.


I do have serious shading issues on my SSW so to me the WNW was a no brainer, it will pay for itself...eventually, but who cares, i'll be generating long into the summer nights(ideal for my aircon) and i'll not be paying my supplier a penny for it.

ed110220

At the risk of sounding like a broken record, you may be better off with the higher wattage (more efficient) panels if you're pushed for space due to the hipped roof. For example BenQ and Sunpower both do 327 or 330 W panels that are roughly the same size as the more common 250 W panels. Therefore you could get practically 4 kW from just 12 panels rather than 16.

They're not triangular though

Ed

Ageing_Stick_Insect

Tunnel, where in the UK are you with air cond needs? Understand need for WNW panels to pay for air cond but the company I got the quote from never considered that roof. Must have had reasons.

ed110220, I couldn't fit any more than 5 standard panels on the SSW roof. Not sure about the ESE one. I'll put it to the quoter next week. I'm still learning about what's possible. 24 small panels is proving expensive so I'm guessing he must have thought of alternatives.

I'm not a triangulist. I can do square or rectangles.

Martyn1981

Ageing_Stick_Insect wrote: »

Tunnel, where in the UK are you with air cond needs? Understand need for WNW panels to pay for air cond but the company I got the quote from never considered that roof. Must have had reasons.

Hi Ray. Hardly anyone does consider 'N' rooves. Which is both sensible and a shame at the same time.

Sensible, because you'd obviously want to use 'S' rooves first, as they generate more leccy.

Shame, because the economics of PV mean that about £2k is needed for non-panel costs (labour, scaffolding, AC side etc). So as an example, a small south facing roof may cost £4k for 2kWp, whilst adding 2kWp of north facing panels might only add £2k more. As the north panels add only 50% to the cost, they become worth consideration, if they can generate 50% or more of what the south system can.

This doesn't of course mean that non south panels are ideal, just that they can make sense if you have to make the most of what you have.

Not sure if installers don't realise this, or just can't be bothered (quite sensibly) trying to convince us, of something that just doesn't sound right. But a quick play with PVGIS comparing generation from different orientations (and pitches) can be quite illuminating.

See FAQ thread section 5:

https://forums.moneysavingexpert.com/discussion/3872445

Regarding my WNW roof, with SE kit, yes it's a gable end, but with the roof for the bay windows taking up quite a bit of space, and like the chimney, adding shading from the SSW.

Some extra info here when I did a 'one year in' summary:

Martyn1981 wrote: »

Thought I'd give a little info on my WNW extension as it reached 1yr old today, and is, shall we say, a slightly unusual idea.

Mart.

tunnel

Hi Ray,


I'm just east of Chesterfield. I have the aircon as I don't like trying to sleep in a warm bedroom, plus it also doubles up as a heater.


Take a look on here where it was discussed in depth.


https://forums.moneysavingexpert.com/discussion/4715287


You may even then consider adding the panels to the back roof....