Have Solar Feed in Tariffs run their course?

ed110220

I can't really see it for the average domestic installation as only a fairly small proportion of the generated electricity can be usefully consumed so the rest would be of no financial benefit without storage technology. It would be different if say you ran some electricity-demanding commercial process during the day and could use all or most of the solar electricity.

rogerblack

Martyn1981 wrote: »

Hiya, probably just splitting hairs, but a non MCS (FiT qualifying) install, would still have to be 'professional'. The roofing work needs to be done well, to prevent damage and leaks, and is structurally sound. The electric side will need to be signed off so that it is accepted by the DNO when the SSEG (small scale embedded generator) is registered.

To avoid DNO involvement, you would probably have to use batteries and a separate household main for selected items (lights, fridge freezer, etc). If you did the simple thing and used a GTI (grid tied inverter) then 'the grid' will have to be told.

There can be no such thing as a non MCS FIT qualifying install.

Unless you can find a MCS registered person to approve the installation - then you absolutely cannot get FIT for it.

If they do approve the installation - then they have to provide certain guarantees about this. Most will, for obvious reasons - be extremely unwilling to do this - or at least to do so cheaply.

I have long argued that FIT is a silly solution - and today what would make lots more sense is net metering.

That is - your meter runs 'backwards' whenever there is solar power available.

Along with more flexibility on installations to allow DIY installs.

If allowed to do this, I'd like to put up about 1000W of solar panels, coupled with large mirrors in front of them (as a side-benefit this would let me repair a shed 'free', by using them as walls).
Total price about £2000, payback in 7ish years, and thence free electricity.


As a technical point - you can grid tie solar panels without FIT - without problems.
It's just you can't get paid export or FIT for them, you just have to notify your DNO.
If the install is below 16A, you don't even need approval, just notification.

MFW_ASAP

ed110220 wrote: »

I can't really see it for the average domestic installation as only a fairly small proportion of the generated electricity can be usefully consumed so the rest would be of no financial benefit without storage technology. It would be different if say you ran some electricity-demanding commercial process during the day and could use all or most of the solar electricity.

Unless you used one of those immersion devices that send the excess to a water tank (which is something I'm also looking at).

rogerblack

MFW_ASAP wrote: »

Unless you used one of those immersion devices that send the excess to a water tank (which is something I'm also looking at).

Solar-thermal is _considerably_ more efficient if you want to do that.
I would go so far as to disqualify from receiving FIT anyone who installs one of these devices and has a gas supply.
Displacing local gas heating basically wrecks all of the assumptions made that justify FITs on the basis of climate change.

MFW_ASAP

rogerblack wrote: »

Solar-thermal is _considerably_ more efficient if you want to do that.
I would go so far as to disqualify from receiving FIT anyone who installs one of these devices and has a gas supply.
Displacing local gas heating basically wrecks all of the assumptions made that justify FITs on the basis of climate change.

I saw a detailed comparison on a renewables website that looked at water heating with PV and Thermal, covering the costs of the panels and ancillary products such as pumps, pipes, expansion tanks, cables, inverters, etc. and maintenance (checking water levels, pumps, antifreeze levels, etc.) and it wasn't that much difference between the two.

With solar thermal, there is also the issue with what to do when the tank has reached its temperature. The pump stops and the tubes/flat plate stagnate. You also don't generate any more energy. This isn't the case with solar PV.

Martyn1981

rogerblack wrote: »

There can be no such thing as a non MCS FIT qualifying install.

Unless you can find a MCS registered person to approve the installation - then you absolutely cannot get FIT for it.

Hiya Roger, I think something got lost in translation, when I said "but a non MCS (FiT qualifying) install", the FiT qualifying in brackets was a definition of MCS, within the context of this thread, particularly regarding the VAT issue. So non MCS is also non FiT.

rogerblack wrote: »

As a technical point - you can grid tie solar panels without FIT - without problems.
It's just you can't get paid export or FIT for them, you just have to notify your DNO.
If the install is below 16A, you don't even need approval, just notification.

But .... the point I was making, is this wouldn't be DIY in the traditional sense, since they would still have to be 'professionally' installed so that they receive approval from the DNO when they are notified. So they will need the appropriate electrical certification, just not MCS.

So going back to the original thread idea, whilst you might be able to do the install, you'd still need it certified to prevent the DNO telling you to cease and desist. So some additional costs, unless you are a certified electrician. And if you are, you might as well do an MCS course and get the FiT too.

Some time back I think I posted the regs about SSEG's, but can't remember when or where. Oops!

[Edit: Found regs, they are here:

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/82784/GuidElectSafety_Quality.pdf

Section 22 Parallel Operation. I think the key bit is the very last paragraph:

"It should be noted that a domestic source of electrical energy equipment must be type tested (regulation 22(1)(a)) and that the consumer’s installation
must still comply with BS7671 Requirements for Electrical Installations
(regulation 22(1)(c))."

So the question is (and I don't know the answer), how do you prove the kit and install meet those regs. Can you just do it right, and tell them, or do you have to supply an electrician's certification that lists the kit and confirms the install specs?]

Mart.

zeupater

MFW_ASAP wrote: »

I saw a detailed comparison on a renewables website that looked at water heating with PV and Thermal, covering the costs of the panels and ancillary products such as pumps, pipes, expansion tanks, cables, inverters, etc. and maintenance (checking water levels, pumps, antifreeze levels, etc.) and it wasn't that much difference between the two.

With solar thermal, there is also the issue with what to do when the tank has reached its temperature. The pump stops and the tubes/flat plate stagnate. You also don't generate any more energy. This isn't the case with solar PV.

Hi

If you have a decently designed system stagnation will be rare, so you'll likely lose very little generation .....

PV with FiT will give a much better payback than thermal with RHI, but good thermal collectors will allow you to pack far more heating capacity onto your roofspace .... Our thermal system is around 1/4 the area of the pv array and will push just as much energy into a cold cylinder as the pv is capable of ... as the heat in the cylinder increases the transfer rate drops, but it usually sits at 1/3 to 1/2 of what would be available from the pv .....

We'll be going down the route of a high COP (/SCOP) air/air heatpump for soaking up excess generation in the shoulder months of the year, effectively multiplying the excess by a considerable factor .... the only issue at the moment is trying to convince MrsZ that the efficiency of some models outweighs the aesthetics of others .... :D ... but that's a story on another thread ...

HTH
Z

MFW_ASAP

zeupater wrote: »

Hi

If you have a decently designed system stagnation will be rare, so you'll likely lose very little generation .....

PV with FiT will give a much better payback than thermal with RHI, but good thermal collectors will allow you to pack far more heating capacity onto your roofspace .... Our thermal system is around 1/4 the area of the pv array and will push just as much energy into a cold cylinder as the pv is capable of ... as the heat in the cylinder increases the transfer rate drops, but it usually sits at 1/3 to 1/2 of what would be available from the pv .....

We'll be going down the route of a high COP (/SCOP) air/air heatpump for soaking up excess generation in the shoulder months of the year, effectively multiplying the excess by a considerable factor .... the only issue at the moment is trying to convince MrsZ that the efficiency of some models outweighs the aesthetics of others .... :D ... but that's a story on another thread ...

HTH
Z

I'm currently looking at a combination of PV and thermal panels, so I don't have an axe to grind in the PV vs Thermal debate. I just thought it was an interesting discussion because I was like the earlier chap and pretty much thought it was cut and dried in favour of thermal.

Now that you've reminded me, I think the FITs skewed the figures quite a bit towards PV, plus the argument was that the area used by the panels would be irrelevent unless you had a small roof and could not fit 4kw of PV on it (and therefore would not qualify for maximum FIT). The argument I guess was that if you had a large enough roof for PV and only put smaller thermal panels on it, then you were wasting roof generation space.

On the point about preventing stagnation, is that achieved by correctly sizing the cylinder, panels, average water usage and average sunlight hours? I'm not sure how you could do this effectively as we generally have grey skies in most of the UK, and so the system would be designed for that, but if we have a glorious summer your design would be compromised. Whereas, the PV would just benefit more from the clear days?

I guess what I'm thinking is that if you size a thermal system to not stagnate on an average day, then you can't change the design if we have well above or well below average?

Ectophile

Martyn1981 wrote: »

[Edit: Found regs, they are here:

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/82784/GuidElectSafety_Quality.pdf

Section 22 Parallel Operation. I think the key bit is the very last paragraph:

"It should be noted that a domestic source of electrical energy equipment must be type tested (regulation 22(1)(a)) and that the consumer’s installation
must still comply with BS7671 Requirements for Electrical Installations
(regulation 22(1)(c))."

So the question is (and I don't know the answer), how do you prove the kit and install meet those regs. Can you just do it right, and tell them, or do you have to supply an electrician's certification that lists the kit and confirms the install specs?]

Mart.

Provided you get a reputable brand-name inverter, it should be type approved, and come with the paperwork to say so. If you buy some cheap Chinese thing off eBay, then it's anyone's guess.

A competent DIYer should be able to meet the requirements of BS7671, provided that they know about electrics. But they would need to read up on how to install it properly, as there are specific requirements for PV installations.

Martyn1981

Ectophile wrote: »

Provided you get a reputable brand-name inverter, it should be type approved, and come with the paperwork to say so. If you buy some cheap Chinese thing off eBay, then it's anyone's guess.

A competent DIYer should be able to meet the requirements of BS7671, provided that they know about electrics. But they would need to read up on how to install it properly, as there are specific requirements for PV installations.

Hiya. Was thinking about this last night, as I'd put together the 'pack' for DNO approval for my extension. Not the normal approach, but couldn't find any installers willing to have a go and the 31/7/12 deadline was fast approaching, so the deal I struck was that I would investigate and prepare the pack.

The inverter test certificates were easy (as you say), just found and downloaded them. And the system schematics also easy, just scanned my current and then put a 'revised' version together for the extension.

The actual G83/2 form was also easy, and I filled it all out using info from the installer. Then sent the 'pack' to the installer, he printed off the form, signed it, and then re-scanned and replaced it in the 'pack' before submitting. Everything was done via e-mail, but a formal approval letter was issued and posted.

But here's my issue. The G83/2 form asks for the installers qualifications, and confirmation that it is installed to requirements. If it's a DIY job, how will the DNO know that requirements are met, without any certification?

Looking at WPD's current forms (the G83/2 is a little different now) but the G83/1 looks fine, it throws up a few hurdles:

http://www.westernpower.co.uk/docs/connections/Generation/Installation-Commissioning-Confirmation-(1).aspx

1. It too asks for the installers "Accreditation/Qualification".

2. 5 declarations that requirements have been met - ok a competent DIY'er may be able to meet these. But

3. Declaration 5 states "The SSEG installation complies with the relevant sections of BS7671 and an installation test certificate is attached."

So my point, way, way back, was that not all certification costs will be avoided, even if it's non-MCS.

I'm not knocking the DIY route, I'm just saying it's not without it's costs, and paperwork. In some countries you can plug-n-play inverters, but in the UK you can't slap one into a socket, it has to be hardwired into the consumer unit, and I suspect this is where the commissioning certification kicks in.

Obviously, DNO approval is crucial when you apply for approval, if you want to carry on operating the system.

Mart.