DIY Install of Solar PV & Thermal panels?

MFW_ASAP

I was just looking at the price of solar panels (both PV and Thermal) and was wondering if the savings from having 5% VAT instead of 20% and feed in tariffs are enough to offset the added costs of having an MCS approved installer?

To set the scene, I'd be installing on a single storey outbuilding and though I'm upgrading the thermal envelope of my house it is rated as 'E' so I'd just qualify for the 6p rate (or whatever it will be this April).

I have the building skills, plumbing and electrical skills to fit the panels, but I would be paying full rate VAT.

ChopperST

Your drawback is that you won't be eligible to receive the FIT payments if you don't use an MCS installer as the install needs to be signed off.

You could ring round local companies and see if any would be willing to sign off your installation for you, but I imagine I know what the answer would be.

MFW_ASAP

ChopperST wrote: »

Your drawback is that you won't be eligible to receive the FIT payments if you don't use an MCS installer as the install needs to be signed off.

You could ring round local companies and see if any would be willing to sign off your installation for you, but I imagine I know what the answer would be.

Thanks for the response. My ain point was whether the fits are worth the extra premium to have the panels installed by an MCS approved installer?

I'm basing this on the evidence that each time the fits have reduced, the MCS installers have suddenly been able to install all of the kit proportionally cheaper. Plus I've seen how much more expensive MCS approved wood burning stoves are compared with those that don't qualify for RHI. An element of profiteering from the installers/suppliers?

mac2008

I like a good spreadsheet so I'll have a go at this for the solar PV:

Sourcing components at retail from swithenbanks.co.uk (all figs inc. VAT @20%)

Fronius inverter: £720
10x 250Wp panels: £1500
Mounting: £720 (2x 5-panel kits)
Switchgear, generation meter, cabling: say £200ish.

Then scaffold etc. Only single story, but safety first etc. Say £400.

So that's £3540.

I got a similar system installed for £5k last year. So £1460 more.

Then assuming savings from electricity are the same in both cases there is the loss of FiT to consider.

Worst case is that you can only get 6.61p/kWh for the FiT and 4.77p export (deemed 50%). Assuming a conservative annual generation of 2000kWh and RPI of 3% this would be be £3400 over 20 years.

If you could scrape a band D EPC and get 14.9p FiT rate, this would rise to £7664.

Or to put it another way, assuming £145pa saving on annual bill, 15p/kWh with 6% energy price inflation:

Payback without FiT: 24.1 years
With 6.61p FiT: 15.4 years
With 14.9p FiT: 10.2 yeas

The above does not take into account inverter replacement cost or any other maintenance, but does degrade the panels by 8% over the period.

Short answer, it is probably worth paying the extra for MCS to get the FiT, especially if you can get the higher FiT.

MFW_ASAP

mac2008 wrote: »

I like a good spreadsheet so I'll have a go at this for the solar PV:

Sourcing components at retail from swithenbanks.co.uk (all figs inc. VAT @20%)

Fronius inverter: £720
10x 250Wp panels: £1500
Mounting: £720 (2x 5-panel kits)
Switchgear, generation meter, cabling: say £200ish.

Then scaffold etc. Only single story, but safety first etc. Say £400.

So that's £3540.

I got a similar system installed for £5k last year. So £1460 more.

Then assuming savings from electricity are the same in both cases there is the loss of FiT to consider.

Worst case is that you can only get 6.61p/kWh for the FiT and 4.46p export (deemed 50%). Assuming a conservative annual generation of 2000kWh and RPI of 3% this would be be £3400 over 20 years.

Thanks for taking the time to run the figures. Did you factor in the extra cost of financing the £1460 for labour in either interest on a loan or lost interest on savings (the £1460 is an upfront cost and needs to be paid one way or another)?

The other issue I have is that the labour costs will unfortunately be far higher because the planning committee are insistent that I fit in-roof panels. There wil therefore be labour costs for stripping the roof, fitting flashing and then refitting/cutting the tiles surrounding the panels - though I guess I could carry out this work myself?

Does anyone have any experience of sourcing the panels themselves and then getting the installer to buy them (and pass on the VAT savings, rather than pocketing them)?

mac2008

MFW_ASAP wrote: »

Thanks for taking the time to run the figures. Did you factor in the extra cost of financing the £1460 for labour in either interest on a loan or lost interest on savings (the £1460 is an upfront cost and needs to be paid one way or another)?

No, the above does not take into account any cost of finance or lost interest on keeping the money in the bank.

Perhaps I'll develop the spreadsheet a bit and make it available for people on this board to use/develop further.

MFW_ASAP

mac2008 wrote: »

No, the above does not take into account any cost of finance or lost interest on keeping the money in the bank.

Perhaps I'll develop the spreadsheet a bit and make it available for people on this board to use/develop further.

It'd be a usefull tool, because as the fits reduce, so do the cost benefits of having an installer, until it becomes like any almost any other job you do on your house - DIY is cheaper (as long as you have the skills to do the job).

Martyn1981

Don't forget to include some costs for the electrician's certification, otherwise the DNO isn't going to approve it, and will ask for it to be disconnected from the grid.

Mart.

MFW_ASAP

Martyn1981 wrote: »

Don't forget to include some costs for the electrician's certification, otherwise the DNO isn't going to approve it, and will ask for it to be disconnected from the grid.

Mart.

I'm currently re-wiring the house and have to do a similar thing there. I'll get an electrician to check the work and 'sign off' on it. Mainly for insurance purposes as electrical work is pretty straightforward. We're talking tens of pounds, rather than hundreds for this sort of service.

I checked the FIT rate post 1st April 2014 and it drops slightly to 14.38p. I've already had roof insulation installed that meets current building regs and I'm about to have high-spec glazing fitted to the house, so I perhaps may be able to scrape a 'D' efficiency rating?

I'll run some figures (thanks mac2008 for the calcs), but given the reduced VAT on the equipment (5% rather than 20% - provided the installer passes on these savings) and the higher FIT payments for a 'D' rating, I think it'll work out better to have the equipment fitted by an MCS registered installer.

I need to get planning permission first though, which is a real pain.

Fruit_and_Nut_Case

Nothing to add but just want to say that I'm finding this thread very interesting. Good luck with whatever route you decide to take, MFW_ASAP.

MFW_ASAP

Martyn1981 wrote: »

Cardiff. 5.58 kWp PV system (2.4 ESE & 1.18 ESE & 2.0 WNW).

Hi Martyn, I've just noticed your signature. My panel orientation will be WSW and ENE. After discussions with the planners, I'll be allowed 2kw WSW, 1.0 kw ENE and 1.5kw on an almost flat roof (slight incline towards ENE).

I'm assuming that I will require 3x DC Isolator, Invertor, Generation meter, AC Isolator. Is this correct and is this the case with your panels?