3kw DIY install

[Rossek9]

Ok being entirely honest, I haven't really looked into the figures much until now.

 

Anyway, it has always been my intention to install a 3kw DIY PV system and forget about the fit payments due to it being so low now.

 

I should add that this will be all south facing with little shading and on a 45 degree pitch.

 

However after completing the details into the solar energy calculator (energy saving trust website) our expected annual fuel bill savings came to £70.

 

The initial outlay for the 3kw in-roof system comes in at £3k. 

 

Does this seem correct? As an outlay of £3k to save £70 a year on fuel doesn't seem worthwhile.

Edited February 6, 2017 by Rossek9

[SteamyTea]

I think they work on 50% of the PV energy being exported.

What annual yield did the EST calculator show for your system?

[Ferdinand]

For a DIY install you need to be considering all your costs. Apologies if you have done this.

 

Here you need to work out how many roof costs you are saving e.g. Tiles. That will change the denominator in your numbers. @JSHarris has a blog about this calculation if you look.

 

I am not totally sure that £1000 per kWp is a best price. I checked with my supplier and they were telling me that a grid linked MCS approved 4 kWp on roof system would be from about £4750 or £1250 per kWp now with them doing everything.

 

I do not think that 20-25% cheaper is very much of a saving for losing the grid tie.

 

I see that your savings with a grid tie would be perhaps an extra £200 per annum on top of your £70. The better option? FIT figures are available some time in advance now, so you can calculate a couple of years ahead.

 

Also solar may influence your EPC value, and potentially capital value of the house, and you may be able to use more than fifty percent of generation e.g. By having a Sunamp or other divert device, which will help the economics of a grid collected system.

 

Your prediction of electricity prices over twenty years may also be relevant. WIll they rise more or less than inflation ?

 

Sorry .. all I can do is draw your attention to other factors that may change the numbers.

 

If it were me, I would do it grid connected on those numbers unless it is impossible, or see if there are other savings I have not allowed for.

 

My thruppence.

 

Ferdinand

 

Edited February 6, 2017 by Ferdinand

[ProDave]

Several points.

 

You should be able to get 3KW of panels and the inverter for about £2000 then you need the in roof kit.

 

that will yield about 2250KWh per year.  IF (and it's a big if) you can use all that yourself, then you will save roughly £330 per year on electricity, so loking ab about a 10 year payback.

 

It all depends on your lifestyle.If you are in during the day and can use what you generate (washing machine etc in the peak daytime) then it might be worthwhile.

 

I am thinking along these lines, but split E/S/W to get a lower, but more consistent and probably more "self usable" generation throughout the day. And I will be considering battery storage to ensure I self use as much as possible.
 

[Vijay]

On the subject of using what the PV generates during the day, what sort of usable output in watts would you likely get on a good and average day?

 

 

[Jeremy Harris]

33 minutes ago, Vijay said:

On the subject of using what the PV generates during the day, what sort of usable output in watts would you likely get on a good and average day?

 

 

 

 

I varies enormously from hour to hour, even minute to minute some days, with a large seasonal variation, too.  For us, November/December are usually the worst months; I think it was the November before last where we had virtually no generation at all for around a week.  We have a 6.25 kWp installation, facing pretty much South, inclined at 45 deg, and that generates around 6,000 kWh/year.   We were lucky, so got in when the FIT cuts were just starting, so although our FIT is still less that the cost of retail electricity, it's not bad.  IIRC, our FIT plus export income last year was about £1000.

 

The PVGIS web site has a tool for predicting what you will get for any location and panel orientation and angle, and in our case it's usually within about 10% of what we really get: http://re.jrc.ec.europa.eu/pvgis/apps4/pvest.php#

[dogman]

Just looked again at the quote for my pv.

 

I had two  roof choices a SE roof or a SW roof 

had looked at a split system using a solaredge and viridian clearline black integrated panels split across both roofs

split into costs

electrics and full installation £2060

12 panels = £4380  total inc all costs £6513

16 panels = £5590  total inc all costs  £7723

 

 

Having second thoughts as seems expensive compared with @Ferdinand post

 

 

[PeterW]

11 hours ago, Rossek9 said:

Ok being entirely honest, I haven't really looked into the figures much until now.

 

Anyway, it has always been my intention to install a 3kw DIY PV system and forget about the fit payments due to it being so low now.

 

I should add that this will be all south facing with little shading and on a 45 degree pitch.

 

However after completing the details into the solar energy calculator (energy saving trust website) our expected annual fuel bill savings came to £70.

 

The initial outlay for the 3kw in-roof system comes in at £3k. 

 

Does this seem correct? As an outlay of £3k to save £70 a year on fuel doesn't seem worthwhile.

 

Wagners have an offer on at the moment at 35.5p/W for JA SOLAR 265W Poly 40mm Alu Frame so 3KW will be £1065 and they have Growatt inverters for £700 or so. Adding in connectors then you're at £2000 or so for 3Kw plus the in roof mounting system costs which are about £500 when you nett off the roof covering savings.

 

As @ProDave says if you can use that yourself then its around £320 per annum of saved power, you may need to look at either a Sunamp or a PV diverter to put the power into stored water though to make the most of it.

 

[Ferdinand]

17 minutes ago, dogman said:

Just looked again at the quote for my pv.

 

I had two  roof choices a SE roof or a SW roof 

had looked at a split system using a solaredge and viridian clearline black integrated panels split across both roofs

split into costs

electrics and full installation £2060

12 panels = £4380  total inc all costs £6513

16 panels = £5590  total inc all costs  £7723

 

 

Having second thoughts as seems expensive compared with @Ferdinand post

 

 

 

Just to be clear mine is ON ROOF, not in roof. I was just making a sanity check on the raw numbers.

 

[dogman]

Anyone got any comparisons quotes. 

 

I will miss the latest fit rate so payback is about 18 years although that is probably my last consideration 

[Auchlossen]

I have just put in 12x285w panels in-roof, cost of kit = £2874 + vat

inc delivery to site

My son put the panels on the roof for a modest fee

Plus fee to  PV installers for wiring and fit application = £950

against which there is saving on roof slates and slater [tho not much saving there, since fiddling around to fit slates on roof beside and above solar panels took as long as slating the north roof.

I am sure that it can be done cheaper, but all installers were excellent.

[Rossek9]

On 2/6/2017 at 07:10, Ferdinand said:

For a DIY install you need to be considering all your costs. Apologies if you have done this.

 

Here you need to work out how many roof costs you are saving e.g. Tiles. That will change the denominator in your numbers. @JSHarris has a blog about this calculation if you look.

 

I am not totally sure that £1000 per kWp is a best price. I checked with my supplier and they were telling me that a grid linked MCS approved 4 kWp on roof system would be from about £4750 or £1250 per kWp now with them doing everything.

 

I do not think that 20-25% cheaper is very much of a saving for losing the grid tie.

 

I see that your savings with a grid tie would be perhaps an extra £200 per annum on top of your £70. The better option? FIT figures are available some time in advance now, so you can calculate a couple of years ahead.

 

Also solar may influence your EPC value, and potentially capital value of the house, and you may be able to use more than fifty percent of generation e.g. By having a Sunamp or other divert device, which will help the economics of a grid collected system.

 

Your prediction of electricity prices over twenty years may also be relevant. WIll they rise more or less than inflation ?

 

Sorry .. all I can do is draw your attention to other factors that may change the numbers.

 

If it were me, I would do it grid connected on those numbers unless it is impossible, or see if there are other savings I have not allowed for.

 

My thruppence.

 

Ferdinand

 

 

The figures do indeed look worth while.

We do not intend to sell anytime soon but i'd like to see the payback around 10 years (a little more would be acceptable)

 

If we can get a MCS 3kw in roof system for around £4k that wouldn't be too far off the mark.

 

I still need to speak to the energy saving trust to see if there is any grants available as this would help with the initial outlay.

[Rossek9]

On 2/6/2017 at 08:08, ProDave said:

Several points.

 

You should be able to get 3KW of panels and the inverter for about £2000 then you need the in roof kit.

 

that will yield about 2250KWh per year.  IF (and it's a big if) you can use all that yourself, then you will save roughly £330 per year on electricity, so loking ab about a 10 year payback.

 

It all depends on your lifestyle.If you are in during the day and can use what you generate (washing machine etc in the peak daytime) then it might be worthwhile.

 

I am thinking along these lines, but split E/S/W to get a lower, but more consistent and probably more "self usable" generation throughout the day. And I will be considering battery storage to ensure I self use as much as possible.
 

 We could potentially use a good amount during the day as I work shifts but could look at setting timers for things like washing machines, tumble dryers ect. Also I was looking at the Sunamp as my intention was to just to use an unvented hot water cylinder.

Edited February 8, 2017 by Rossek9

[Nickfromwales]

Im sure I've asked elsewhere, but can you export to the grid if you DIY?

[Rossek9]

9 minutes ago, Nickfromwales said:

Im sure I've asked elsewhere, but can you export to the grid if you DIY?

My guess would be you could but couldn't claim the fit payment.

 

Someone else more in the know than me might correct me if I'm wrong through.

[SteamyTea]

As far as I know you can export to the grid without a MCS certificate.  You need to contact your local Distribution Network Operator (DNO) who should be able to advice on what paper work is needed (every PV, wind/water turbine, diesel generation system is logged with them).  You will also need to use certified equipment to automatically disconnect in case of a fault.

[Nickfromwales]

Cheers. Just wondering if you'd get revenue from export after your own consumption if you weren't fitting via MCS. 

Edited February 8, 2017 by Nickfromwales
Crossed with ST

[Ferdinand]

I *think* for grants on solar for newbuild you will be whistling in the wind. But I could be wrong :-) . Special circumstances, perhaps?

 

I think that grants for solar are not available any more for refurb either - it is really cheap so why should they throw public money at it?

 

There may be wrinkles you can exploit - eg the possibility of getting it VAT free if allowable as part of your newbuild etc, or better interest rates from Ecology if those are still available.

 

But note that I know more about refurb grants (which except for loft insulation and small amounts in eg EWI all seem to be means tested).

 

Ferdinand

[SteamyTea]

19 minutes ago, Nickfromwales said:

Cheers. Just wondering if you'd get revenue from export after your own consumption if you weren't fitting via MCS. 

Not easily as far as I know.

Was the main reason for the MCS system.  The only way I know of is to contact a power company and see if they want to buy some, then pay your tax on it.

[Jeremy Harris]

I don't think they took away the export payment scheme when they introduced the FIT, so I believe you can still do as some did before the FIT was invented and fit an export meter (not a generation meter as normally fitted) and get paid the export rate for everything that goes to the grid (close to wholesale rate, around 4.5p/unit, IIRC).

 

It'd probably be a bit of a nightmare getting anyone to acknowledge that you can still do this, but there are a few hundred microgeneration schemes that have been around since well before the FIT was invented that still do just this.

Edited February 8, 2017 by JSHarris

[Roundtuit]

Hi.  For what it's worth, I've just had an integrated 4kw Viridian Clearline Fusion system put in for £5.3k, all in.  I reckon I could have done it cheaper, but the installers are linked to the roofing company, so it took some of the hassle and risk out of it for me.  It also saved 32 sq m of slating to off-set the cost.  Probably also worth mentioning that the local conservation officer has taken a particular interest in this site, so aesthetics were quite high up the priority list...

 

[dogman]

@RoundtuitDo you mind if i ask who the installer/pv company is. The same system for me is £7723 with a solar edge inverter.

You are not a million miles from me so they may travel 

[Steptoe]

33 minutes ago, dogman said:

@RoundtuitDo you mind if i ask who the installer/pv company is. The same system for me is £7723 with a solar edge inverter.

You are not a million miles from me so they may travel 

Installers will travel, if the money is right,.  

End off 2015 beginning 2016 I was doing over 2000 miles a week before the FIT ran out,! 

[Rossek9]

£5.3k for a 4kw in roof system doesn't seem too bad.

 

Works out at £1350 per kw.

 

Would be interested to hear company as well at these prices.

 

This is an mcs system registered for fit?

[Roundtuit]

Yes - mcs registered, from Manor Solar based near Peterborough. As the roof is being done by their sister company, it may be that there has been some off-setting of costs that isn't fully visible, but the total cost of the job isn't a million miles out. To be honest, it hasn't all been plain sailing (pm if you want details), but I can't fault the quality of the roof installation ( and I've crawled all over it!)