Massive changes to G83 rules for solar PV installations needing advance permission

[Gavin A]

A new draft version of the G83/2 regulations has been released for consultation including major changes to the rules about when advance permission is needed for connecting a solar PV system to the grid. These changes have massive implications for the industry as a whole, but particularly for local installation companies with a large local customer base.

The key changes are:-

Definition of 'Close Geographic Region'

Any installations of more than 1 solar PV system by the same installer that fall within either of these categories would require advance permission to be connected, using a revised Appendix 2 multiple installations application form.

1) The postcodes of any of the premises where a SSEG installation is planned by the same organisation are the same when the last two letters are ignored…ie AB1 2xx where xx could be any pair of letters or where x could be any letter.

2) The premises where a SSEG installation is planned by the same organisation are within 500m of each other.

These rules wouldn't only apply to new installations, but also to all solar PV system that have ever been installed in that 'close geographic region' by the same installer.

This procedure (single premises connection procedure) will not apply where an Installer plans or has already installed other SSEGs in

a Close Geographic Region; in this case the procedure in 5.1.2 shall be followed.

Failure to comply with this requirement may lead to the disconnection of the Customers Installation under ESQCR (26) or failure of the SSEG to operate as intended.

So any installer who carried out an installation within the same postcode area AB1 2XX postcode area or within 500m as another installation they'd carried out, and didn't ask for permission in advance would risk the DNO cutting installation off at any time in the future if any problems did arise with the local grid in that area.

This is a massive change for the industry, that will particularly hit the sort of quality local installers that use this forum who will have most of their work in postcode districts that they've already installed systems in, and will therefore need advance permission to connect them, whereas new start ups, or none local companies could install the same system without needing any advance permission.

Full details and analysis on the Leeds Solar blog please take a few minutes to read this and think about the potential consequences to your business, then email Ofgem to let them know what you think of these proposals before 28th September 2012 [email protected]

 

[Gavin A]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

sorry, the formatting got a bit messed up for some reason.

 

[whinmoor]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

Agreed, Gavin.

Some of the proposals seem bizarre and quite arbitrary. How do you judge 500m? As the crow flies or by road?

The time delay would be a major headache. A few weeks ago we quoted for 240w panels. Customer took a week or two before accepting. Went back to supplier and they were now selling 245w panels which we bought and fitted. This would be a pain if DNO pre-notification was for 240w.

I guess the next stage will be for the DNO to start charging for applications/notifications.

 

[Gavin A]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

my initial email to ofgem, just to get the ball rolling...

Hi Gareth,

I've just read through the latest draft G83/2 proposals, and realised that there are some huge changes to the process for determining whether a sub 16amp system should be required to obtain advance permission to connect hidden away in this document.

I have to ask you to withdraw these proposals, and have an urgent rethink on them, as they will be completely unworkable, and cause companies such as ours to be operating at a major disadvantage in our own local areas compared to other companies who've not got any previous installations in our popular postcode districts.

I'm also certain that this measure will cause the entire G59 and G83 application process to grind to a halt under the volume of new applications it will create. These systems are already close to collapse in many areas, with applications across Northern PowerGrid taking up to 65 working days to be processed, and if we have to wait 45 or 65 working days for permission to carry out a basic sub 16amp installation this will likely mean we'll not be able to promise to carry out those installations before the next quarterly FIT cuts happen.

Put simply, this measure as proposed will put most reputable local solar installers out of business overnight, with only rogue traders, and companies that operate outside of specific geographic areas left... or we'll have to stop doing local work, and focus on working in areas we've not previously worked in, which would be a ridiculous policy result.

I must remind you of Ofgems stated purpose of "eliminating unnecessary regulatory and market barriers to the economic deployment of distributed energy."

How does this policy possibly meet that aim?

Please withdraw this idea, and go back to the drawing board with it. I'd be happy to work with you and others in the industry to draw up a workable solution to achieve your presumed goal of stopping local grid connections from being overloaded with PV installations, but this policy will be an absolute disaster if you go ahead with it.

I've put further analysis of this issue on our blog at this link, if you want to see more details about our analysis and objections Major changes to G83 rules for properties needing advance permission to connect - Leeds Solar | Solar installers blog and renewable energy industry news

 

[SolarCity]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

Thanks for the info, Gavin, and great email too. I share your concerns with this.

I can imagine the situation now: You get a phone call to go and see a customer, they wish to offer you the work and the question comes up: "Will you fit me in before the deadline?". Because of this proposal, the answer will very likely be "No". But the other more expensive firm will have no such barriers as they are a nationwide firm. This is an utterly ridiculous burden to place on us - unless, perhaps, the DNO start giving answers within 3 working days.

 

[SolarRoofSols]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

Thanks for the heads up on this, it would be a disaster for all of us. Response is being sent as I type!

 

[SolarRoofSols]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

The fact that a pre approval doesn’t need to be submitted by a company that has not installed in the area is totally nonsensical. If it is accepted retrospectively via another installer then what does it matter who has done the installation?

 

[John Allen]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

Yet another example of the stumbling blocks put in the way of SME installers. The only way that I can see this would be viable on a domestic level is if they allowed the FIT rate to be back dated to the date of the DNO application

 

[Eco Deal]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

does not make sense !!! why would it matter if you have installed their before or not?

thanks for the heads up

 

[pvman]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

Below is a cut and paste from an email, might be useful for people who want to raise the above points to ofgem.

Ofgem hosted a series of regional forum events in 2011 focusing on the issues facing Distributed Generation customers when connecting to the network. A number of measures have been put in place over the past year as a result of the discussion and we are holding follow-up events on the following dates:

• London 22 October 2012
• Glasgow 26 October 2012
• Cardiff 30 October 2012

In advance of the events, we have published an open letter on our website, inviting feedback from the DG community on the progress made to date in improving the experience of getting connected.

This is the open letter link

http://www.ofgem.gov.uk/Networks/ElecDist/Policy/DistGen/Documents1/Open_letter_DG_Forum_170812.pdf

Tom

 

[mechelec]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

does not make sense !!! why would it matter if you have installed their before or not?

thanks for the heads up

it can make a big difference to the DNO network if you have multiple sseg on one leg of a substatiion as it can cause reverse current flow and voltage rise at the point of common connection to other connected customers. If this was to happen on multiple legs on one substation then it can cause reverse current flow on the 11kv network as well.
This why it is important for the DNO to receive Pre applications for sseg in one area.
I guess from your response you only fit and do not design ?

 

[Ian-LS]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

it can make a big difference to the DNO network if you have multiple sseg on one leg of a substatiion as it can cause reverse current flow and voltage rise at the point of common connection to other connected customers. If this was to happen on multiple legs on one substation then it can cause reverse current flow on the 11kv network as well.
This why it is important for the DNO to receive Pre applications for sseg in one area.
I guess from your response you only fit and do not design ?

I think he was referring to the fact that the proposals mean that Company X who has installed a few PV systems in the postcode LS16 5** (as we have) has to get permission to install another PV system in this area whereas Company Y who has not installed a PV system in that area will be able to connect a PV system without needing permission from the DNO. This is completely nonsensicial and is not a level playing field.

I can see why they dont want to overload one substation but to propose a LS16 5** limit is frankly unworkable

 

[mechelec]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

I think he was referring to the fact that the proposals mean that Company X who has installed a few PV systems in the postcode LS16 5** (as we have) has to get permission to install another PV system in this area whereas Company Y who has not installed a PV system in that area will be able to connect a PV system without needing permission from the DNO. This is completely nonsensicial and is not a level playing field.

I can see why they dont want to overload one substation but to propose a LS16 5** limit is frankly


He asked "why would it matter if you have installed their before or not ?" no mention of anyone else being able to or not I just answered a question.

The DNO keep records of sseg installed and can check how much is installed in a given area. If a company chose to send in separate commissioning confirmations within a short space of time for the same area this would be classed as multiple sseg even though the company had not submitted them at the same time and the DNO would be within their rights to request a disconnection if thes systems were causing a problem on their network. The chances of multiple companies fitting individual sseg on one ss feeder would be pretty slim.

 

[Ian-LS]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

I think he was referring to the fact that the proposals mean that Company X who has installed a few PV systems in the postcode LS16 5** (as we have) has to get permission to install another PV system in this area whereas Company Y who has not installed a PV system in that area will be able to connect a PV system without needing permission from the DNO. This is completely nonsensicial and is not a level playing field.

I can see why they dont want to overload one substation but to propose a LS16 5** limit is frankly


He asked "why would it matter if you have installed their before or not ?" no mention of anyone else being able to or not I just answered a question.

The DNO keep records of sseg installed and can check how much is installed in a given area. If a company chose to send in separate commissioning confirmations within a short space of time for the same area this would be classed as multiple sseg even though the company had not submitted them at the same time and the DNO would be within their rights to request a disconnection if thes systems were causing a problem on their network. The chances of multiple companies fitting individual sseg on one ss feeder would be pretty slim.

Define a short space of time? This is a very grey area, at the moment mutilple SSEG comes into affect when installing more than one <16 Amp per phase install on the same street or postcode. So if we installed a system in January 2012 on one street then 9 months later came back and installed a system 200 yards down the road, We should technically be gaining permission but another company who didnt install the first PV system wouldnt need permission as far as I understand.

And on your last point, its not one SS feeder though the consulation is proposing we would need permission based on LS16 5** (or within 500 metres) where there must be dozens of substations. I would agree the chances of multiple companies installing into one substation are slim but this is not what the consulation is suggesting will happen but the fact such a obvious loophole for large national companies is just taking the micky a bit

 

[PeteC]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

consultancy report

http://www.ofgem.gov.uk/Networks/Techn/TechStandds/Documents1/7789 - Ofgem G83-2 Review - R2.pdf

dc injection interesting part~ concerns micro-inverters more; also DNO highlight responsibillity of damage to their equipment.

 

[SolarRoofSols]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

I wanted to bump this up to the top again to encourage people to log a response to Ofgem clarifying how bad clause 5.1.2 could be.

It will mean that for those of us relying on local marketing/word of mouth whereby you could pick up a couple of jobs on the same street, you will have to pre apply for G83 connection for the 2nd job (an any other job within 500m for that matter), but a competitor can go ahead and do a post notification.

Not so bad in a slow market but what happens a week before the next FIT cut and you have a few houses within 500m of each other wanting a quick install? Can yo afford to lose the job to someone else, maybe an out of town competitor?

If they are going to implement it then it should be one rule for all!

 

[Gavin A]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

Ofgem asked me to clarify what the exact changes were that I was objecting to, so I thought I may as well add my response to this thread for reference.

If you've not already responded, please take a few minutes to email Ofgem either with your own objections to this, or merely to support the position I've outlined to them - just reference Leeds Solar, and quote my email below, and state your support for this position if you've not got the time to write your own email.

Contrary to my original thoughts on this, I've now checked and realised that this proposal was in the version that was consulted on in February, but this consultation was released about 2-3 days before the announcement of the 3rd March FIT cut, so I assume that most installers were too rushed off our feet to stop and read through this consultation in enough detail to pick up on this change (the FIT consultation was also in progress at the same time). This makes it far more likely that this change will go ahead unless they now get deluged with objections to it, so please get on it and object before we're all landed with a piece of beurocratic nonsense that's even worse than the EPC requirements.

[FONT=&quot] the changes concerned relate to the changes to the situations where prior application to connect a sub 16amp per phase system is required, and are 2 fold:

referencing
G83/1 5.1.2
G83/2 definitions, close geographic region, & 5.1.1

1 - Change to the definition of close geographic region

G83/1 gives no definition of 'close geographic region', but gives 2 examples of 'in the same road / street' or as part of a new housing development.

G83/2 defines 'close geographic region' as being a either the postcode area excluding the last 2 digits, so LS16 5XX, or within 500m of the installation.

This is a massive change to the area affected, taking it from basically involving the immediate neighbours within sight of the installation on the same street, or within the same development, to covering an area of up to several thousand houses and in some cases up to 25 miles in length.

FYI we're currently in the middle of a stage 2 application with Northern PowerGrid for around 250 properties in Goole, and they've been happy for us to submit the applications in postcode districts or for the same street, and ignore any that were the only installation in that postcode or street, even though they're virtually all in the same AB1 1XX postcode area.

The current situation is a reasonable approach to determining if multiple installations in a close area are likely to have an impact on the same phase of a local transformer or not. The revised versions have no such logical justification, as they will almost always cover dozens of transformers, which as I understand it, operate independently, so there's hardly any impact on one transformer from having sub 16amp SSEGs installed on other local transformers.


2 - Changes to the frame of reference for projects from 'planned projects' in G83/1 to 'plans to orhas already installed other SSEGs' in G83/2

Changing from a situation where advance permission is only required for planned projects involving multiple installations to a situation where any project previously installed by an installation company will mean that all future installations in a wide geographic area around that existing installation is a huge change.

It is a change that will lead to experienced local installation companies being at a serious disadvantage in their own local area, as they will inevitably already have installed SSEG's in many of their local LS16 5XX postcode districts, and will therefore have to apply for advance permission to connect for any proposed installations in their local area that happen to be within that same postcode district.

A new installer, or installer from outside the area wouldn't need to request advance permission at all, and could simply install the exact same system under G83/2 stage 1 immediately and just notify the DNO within 28 days afterwards.

I can only assume that this wording slipped in without anyone really considering its impact. If you do leave it in place though I can't see that many companies will have much option other than to ignore this rule or go out of business, so I'd hope you'd not force otherwise compliant companies into such a position. I'm pretty sure this measure would be illegal as it would unfairly discriminate between one company and another, so would expect it to be unenforceable anyway. Effectively then, all it would do would be to grant the DNOs an excuse to cut such installations off at their discretion, which is surely not a situation the regulator should be creating.

We'd be happy to participate in discussions to find a more workable method of determining when advance permission should be required.[/FONT]

 

[SolarCity]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

I think this is pretty important to a lot of installers so I'll make it a sticky for now

 

[Energetic]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

I have emailed gareth to support your argument. We are ** *** **** **** *** ***** if this is applied retrospectively.

 

[LightGEN]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

I've mailed Gareth my own missive. Besides the obvious observations relating to local businesses beind disadvantaged, I've suggested that, should this change be forced through, there be a requirement for on-line systems through which to make requests and a requirement for a three day turn-around.

 

[Gavin A]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

I'd settle for 14 days tbh

 

[LightGEN]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

I'd settle for 14 days tbh

I've taken the 'start low and negotiate up' approach, but I'd settle for them dropping the idea altogether.

 

[Nextgen]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

Hello Gavin
We have installed 2 systems on to adjoining semi detached properties and one further down the same road (about 60 metres away), all three are sub 16a. Do I understand correctly that under this proposal, if there is a grid problem that the DNO could order the disconnection of one or all systems.

 

[Gavin A]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

definitely under this proposal.

If you installed them all as part of the same project, you'd have needed permission even under the current rules as they're that close to each other, but this would now apply to a much wider area, and to mean you need to ask permission for any new systems in advance if you've previously installed a system in that geographic area.

consultation closes on Friday btw, please get responses in.

 

[Gavin A]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

times up folks.

If this comes in and you've not responded and knew about it, then you're partly responsible in my eyes.

Possibly a little harsh, but I'm currently well ****ed off with BPVA for saying they'd alert their members to this, but then not doing so. It's a quitting issue for me as well with regard to BPVA, final straw and all that.

 

[LightGEN]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

This morning I received an email back from Ofgem, which in short states "We have noted your concern about the way that the Stage 2 application process could work under the proposed G83/2. We have discussed this with the DNOs and have agreed a revised approach that addresses these concerns." Parties who responded to the consultation are being invited to partake in a conference call where this 'revised approach' will be discussed.

 

[Energetic]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

Got one also, slightly concerned about the length of the list of email adresses on the top but at lease they've taken notice. Well done Gav and everyone who responded.

 

[Ian-LS]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

I even tweeted solar power portal, solar trade association and BPVA numerous times.

So what was it 6 people that responded?

 

[Energetic]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

theres 8 on mine but might not be everyone...

 

[Ian-LS]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

A bit concerning that it was on this forum and navitron and also 500 people viewed our blog about this issue, and only 9 people responded.

This is something the trade associations should have picked up on and didn't even when told that this would be a major issue if the plans were to be implemented. If BPVA didnt even respond to the consultation then that is frankly shocking, I hope they did respond though.

 

[SolarRoofSols]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

I got the email as well - it is shocking if no one else has responded...no doubt they will be the folks complaining to high heaven if the change does go through!

We are not members of BPVA and to be honest we won't be if they are not even alerting their members to silly changes like this which will have an impact on completing installations when there are fit cut deadlines to meet! Grrrrr

 

[Worcester]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

They might be being selective or else there may be a spam issue, - we responded haven't got an email response (yet) others may not know that a response has been sent out becasue of that.

 

[Energetic]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

Close Geographic Region
A close geographic region[1] is one that meets at least one of the following criteria;

1) The postcodes of any of the premises where a SSEG installation is planned by the same organisation are the same when the last two letters are ignored…ieAB1 2xx where xx could be any pair of letters or where x could be any letter.

2) The premises where a SSEG installation is planned by the same organisation are within 500m of each other.
[1] This represents an area typically served by a single low voltage feeder circuit fed from a single distribution transformer.


This is from yesterdays email, effectively the concerning bits have not been changed. There is a 28 day limit though...

In our local postcode we have 19 installs within their definition of a Close Geographic Region We know that ther are on at least 5 different substations possibly many more, We are a very locally focussed company in a small town. There are many more installs by other installers in the same postcode.

 

[TedM]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

I'm not sure what they mean by "a single distribution transformer."

Here, in a very rural area, we have all power coming from individual 11kV overhead lines with a transformer almost for each house. I'm guessing that the "distribution transformer" means that feeding the 11kV line, not the 11kV/240V ones.

Our postcodes also cover large areas - the one for our house covers a road 1.5 miles long. There are probably 100 11kV/240V transformers within a single postcode and possibly thousands within the AB1 2xx equivalent area.

 

[Ian-LS]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

I'm not sure what they mean by "a single distribution transformer."

Here, in a very rural area, we have all power coming from individual 11kV overhead lines with a transformer almost for each house. I'm guessing that the "distribution transformer" means that feeding the 11kV line, not the 11kV/240V ones.

Our postcodes also cover large areas - the one for our house covers a road 1.5 miles long. There are probably 100 11kV/240V transformers within a single postcode and possibly thousands within the AB1 2xx equivalent area.

Those on this conference call, please argue our corner in a calm manner. We understand what they are trying to do by not having single transfomrers and substations overloaded but these proposals will not acheive this and are unworkable as they currently stand.

Everyone I have spoken to about this issue has been firmly behind our and other installers stance

 

[Vrai]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

Thanks for the info.

 

[Gavin A]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

Some brief feedback on the teleconference yesterday...

Generally constructive, with Ofgem open to our concerns, and pretty much all the installers saying the same things as far as I could tell.

Key points raised were

1 - Timescales for DNO's turning around stage 2 applications should be reduced from their current 45 day maximum, otherwise apart from anything else, it will result in a situation where installers are better off just waiting 28 days and doing it anyway.

2 - Geographic area definition is still far too wide, and the guidance note about it referring to an area served by 1 substation currently just confuses the situation and leaves the entire thing open to interpretation by the DNO / OFgem at a later date that could result in a customers installation being cut off. Ofgem were saying that the new guidance note was intended to clarify the situation so that it would only apply to systems that are actually installed on the same transformer - in which case this would be much much better as it would mean that we as installers could use our own judgement - eg if there's a transformer in the field then there's not point worrying about an installation carried out 20 miles away that just happened to be in the same postcode district.

3 - Suggestions made about alternative lower limits of systems size eg 2.2kW below which there would never be a need to prenotify the DNO - unlikely to make it into the current version, but could be looked at in future.

4 - Suggestions made about a database being made available to installers showing areas where there were known problems already, so installers could avoid them, and potentially this could be a better solution than the current proposal - OFgem were interested in spreading the idea as a voluntary best practice idea, but it's not going to replace the current proposals.

5 - Suggestions made about investigating / adopting the German solution of inverters that reduce their output to limit localised voltage spikes or overall high frequency issues, instead of the inverters being either 100% on, or 100% off. As virtually all inverters have this capability built in anyway it should be relatively simple to adopt this approach, which would then fully solve most of the concerns the DNOs have around localised over voltage issues. Ofgem seemed interested in this, but it's too late for it to make it into G83/2.

G83/2 is scheduled for publication at the end of this month, so it seems unlikely that anything other than minor tweaks are going to happen between now and then.

 

[Noddy67]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

"This procedure (single premises connection procedure) will not apply where an Installer plans or has already installed other SSEGs in..


isn't it only for the 28 days previoius and 28 forward... so you could do 3 installs in 57 days. It's not 'ever' from my reading.




Read more: http://www.electriciansforums.net/p...needing-advance-permission.html#ixzz29rtSYeUu

 

[Gavin A]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

"This procedure (single premises connection procedure) will not apply where an Installer plans or has already installed other SSEGs in..


isn't it only for the 28 days previoius and 28 forward... so you could do 3 installs in 57 days. It's not 'ever' from my reading.

that's what it has now been changed to AFTER the intervention of around 8 companies, mostly those involved on this thread.

It's far from perfect still, but is a hell of a lot better than the situation would otherwise have been.

 

[Noddy67]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

apols - i was reading this out of order...

 

[mdovey]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

5 - Suggestions made about investigating / adopting the German solution of inverters that reduce their output to limit localised voltage spikes or overall high frequency issues, instead of the inverters being either 100% on, or 100% off. As virtually all inverters have this capability built in anyway it should be relatively simple to adopt this approach, which would then fully solve most of the concerns the DNOs have around localised over voltage issues. Ofgem seemed interested in this, but it's too late for it to make it into G83/2.

From a technical viewpoint this may be simple - from a FIT perspective, this looks like a minefield.

The current FIT is based on how much is generated, not how much is actually fed into the grid. If the panels of a system are generating at 3KW but the inverter is limiting the output to 1KW due to local grid issues, then the FIT should be based on 3KW not 1KW, i.e. on existing installations any limiting should be done between the generation meter and the grid, not at the inverter. Otherwise I can see some nasty court cases against OFGEM/DECC that this was a retrospective change to the FIT contract or with solar installers for mis-selling for not taking this into accounts in their financial forecasts.

This could be introduced for new installations. However, it will make the financial projections even harder to produce, and could even further impact sales - how many would install solar knowing that there is a risk that payback period if one of their neighbours installed a generation facility which resulted in the inverter throttling the output!

Matthew

 

[Gavin A]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

From a technical viewpoint this may be simple - from a FIT perspective, this looks like a minefield.

The current FIT is based on how much is generated, not how much is actually fed into the grid. If the panels of a system are generating at 3KW but the inverter is limiting the output to 1KW due to local grid issues, then the FIT should be based on 3KW not 1KW, i.e. on existing installations any limiting should be done between the generation meter and the grid, not at the inverter. Otherwise I can see some nasty court cases against OFGEM/DECC that this was a retrospective change to the FIT contract or with solar installers for mis-selling for not taking this into accounts in their financial forecasts.

This could be introduced for new installations. However, it will make the financial projections even harder to produce, and could even further impact sales - how many would install solar knowing that there is a risk that payback period if one of their neighbours installed a generation facility which resulted in the inverter throttling the output!

Matthew

I take your point, however if the alternative is for the system not to be allowed at all, or for only a smaller system to be allowed, I think this option is generally preferable.

Your suggestion on the point at which this should be applied is a complete technical non-starter IMO, and possibly a dangerous one at that. If throttled at the inverter, it uses the MPPT system of the inverter to throttle the output entirely safely by adjusting the voltage point it's drawing power from the panels at to a less efficient point. If throttled on the AC side of the inverter then the only method of throttling the system is via a heat dump or similar, which while technically possible, is going to add significantly to the costs and complexity of the systems, and lead to the potential for 2kW+ heat dumping for long periods in peak summer which is unlikely to be a desirable situation, and if mounted in the wrong place could pose a fire risk (I know of someone who's house burnt down due to a similar heat dump unit used in an offgrid system).

Possibly you could look at allowing the use of immersun / emma style load management as an alternative option, but the problem with these units would be that they're only capable of storing a certain volume of excess energy in the hot water tank before they stop working, at which point the full generation would be sent back to the grid. I'd therefore see them as being supplementary measures that we as installers could recommend to customers to minimise the levels of reduced output, rather than actually being an alternative method of safeguarding the grid in the way that the inverters can do. Apart from anything else, the inverters already have to be g83 compliant, whereas these units don't, and I don't see that it's going to be an advantage to have to pay the additional costs involved in getting them type tested.

I'd be very surprised in most cases if this led to more than a 1-2% reduction in output through the year, and it's a simple enough matter to factor such reductions into your calculations, especially if it's mitigated with the use of an Immersun. It's certainly worthwhile if it allows for a 4kW system to be installed instead of a 2kW system, or no system at all, or is an alternative to not being allowed to install for 28 days which means missing a FIT cut deadline.

Put simply though, if we're going to get anything close to the 20GWp of solar PV installations being discussed, then we will have to adopt these measures at some point to prevent severe localised grid problems, or there simply not being enough capacity on the grid to take that level of uncontrolled SSEG connection. It's far far better to implement this measure before it becomes a significant problem, as the more widespread the implementation of the measure, the less severe the restrictions need to be on each individual sseg.

 

[mdovey]

Re: Massive changes to G83 rules for solar PV installations needing advance permissio

Yes, it did occur to me that a limiter after the generation meter wouldn't be a great idea, due to the need to dump the energy somewhere.

If the impact really is only 1-2% then there is unlikely to be an issue but if it is much higher it would have impact, and it would only need a few well reported cases of examples of higher limiting to further damage sales (even if these cases were abnormal).

I'd also be concerned that the DNOs would just use this as an excuse not to invest in the infrastructure needed to make the best use of micro-generation.

I do take your points the alternatives aren't great either.