If you have read a general guide to G98 anywhere, it will have told you that you have 28 days from commissioning to get the form in.
SP Energy Networks says 30.
That is not a rounding error or a rewording. Its single-premises page states that the installation commissioning confirmation must be completed and submitted within 30 days of commissioning, and SPEN is the only one of the six network operators in Great Britain that publishes that figure. Everyone else says 28. So if your operator is SP Energy Networks, the deadline in the national guides is not your deadline, and there are two further differences on this page that matter more.
SPD or SP Manweb — which one are you?
SP Energy Networks is two separately licensed distribution businesses: SP Distribution (SPD) in Scotland, and SP Manweb (SPM) in England and Wales. Its own description of the territory covers central Scotland and the south of Scotland, plus North Wales, Merseyside, Cheshire and North Shropshire. Between them they form one distribution network under one brand, with one set of application forms.
Check the first two digits of the MPAN on your electricity bill:
- 13 — Cheshire, Merseyside and Northern Wales. SP Manweb.
- 18 — Southern Scotland. SP Distribution.
Two things worth flagging. North Shropshireappears in SPEN’s own description of its patch but not in the licence-area label, which surprises a fair number of Shropshire residents who assume they are with National Grid. And distributor 17 is Northern Scotland, which is SSEN, not SPEN — the Scottish split runs roughly along the Highland line and catches people out constantly.
And yes, SP Energy Networks and ScottishPower share a corporate parent. The networks business is regulated separately from the supply business: SPEN owns the local network whether or not you buy your electricity from ScottishPower, and buying from ScottishPower does not mean SPEN is your operator.
Tell them before you commission, not after
Here is the second difference, and it reverses the sequence most guides describe:
“If you wish to install a single generator of less than 16A/phase (3.68kW), you must inform us of the proposal before or at the time of commissioning. This is a legal obligation, details are defined within the Electricity, Safety, Quality and Continuity Regulations 2002.”
Before or at the time of commissioning. Not afterwards.
Compare National Grid Electricity Distribution, which states in terms that you may install and commission the generation before providing any information, and simply return the paperwork afterwards. Two operators, opposite instructions, both quoted from their own websites. This is precisely why a single national “how to notify your DNO” page cannot serve everybody, and why we have written these one operator at a time.
In practice SPEN is describing a two-stage process — inform it of the proposal, then confirm the commissioning — with the confirmation due within that 30-day window. Whether an operator would take issue with a plug-in device that was connected first is not something we can tell you. What we can tell you is which instruction SPEN publishes.
The two SP Energy Networks dates
What SPEN asks you to attach
The third difference, and the one with no clean answer for plug-in solar.
SPEN’s single-premises page requires more than the form:
“You must attach the final copy of the circuit diagram and SSEG Test Report (with computer printout of protection settings if applicable) in line with the G98 requirements.”
The circuit diagram is the easier half, and it is worth saying that it is not actually a SPEN speciality — an earlier version of this page implied it was. Every operator’s copy of the ENA Form B carries the same declaration: “I enclose a copy of the system schematic which has been left on site at the Customer’s incoming meter location.” A schematic is universal. What SPEN adds on top is the SSEG test report and the protection-settings printout.
For a plug-in device the drawing is manageable — panel, microinverter, factory-fitted lead, BS 1363 plug, socket outlet, with the inverter’s make, model and rated output labelled. There is no additional wiring to draw, because the plug is the connection and the means of disconnection both. Which raises its own problem, because Form B also asks for the Location of Lockable Isolation Switch, and a 13 A plug is not one.
The SSEG test report is harder. An SSEG test report is the document a commissioning engineer produces after testing a small-scale embedded generator’s protection settings on site. For a factory-assembled product that arrives sealed, with type-tested protection settings the owner cannot access or adjust, there is no engineer to produce one and nothing on site to test. The requirement was written for installed systems, and a plug-in solar device is not one.
We do not know how SPEN intends to handle that, and we are not going to invent an answer.
If you are in a SPEN area, ask them this question directly before you submit, and keep the reply. It is the single most useful thing you can do, and a dated record of having asked puts you in a materially better position than an incomplete submission.
Where to send it
SPEN publishes the forms clearly, on a page called Application Forms and Guides, and the process you want is the one it calls Single G98 Generator Connections — a single installation at one premises. Form B, the installation commissioning confirmation, is a Word document that appears in two places under slightly different filenames, both current. Form A is the multiple G98 generator connections application. Form C is the type test verification report, which manufacturers complete as part of certification rather than something owners apply for.
If you have arrived from SPEN’s Connecting to the Grid pages and found yourself reading about a G99 application, back out. The G99 process covers generation above 16 A per phase and involves a technical assessment and a formal approval to connect. The requirements for connecting a device of this size are far lighter.
Where to sendForm B is less clear. SPEN’s single-premises page says the details can be found on its customer connections page and links there, but that link did not resolve to a submission address when we checked on 10 August 2026.
SPEN’s distributed generation contacts page lists design team addresses for Scotland, Cheshire, Wales and Merseyside, but those are connection design contacts for schemes up to 49.9 MW, not a G98 notification inbox, and we would not use them for this. Ask, rather than guess.
Form D — the part nobody mentions
SP Energy Networks publishes a G98 Micro-Generator Decommissioning Confirmation, Form D, for telling it when generation comes off the network.
Almost nobody writing about G98 mentions Form D exists, and for plug-in solar it is about to matter more than it ever did for rooftop systems. IPS version 2 requires the permanent marking on the device to state that notification about connection and disconnection is mandatory, with a link to instructions; separately, the information supplied with the device must cover registration and deregistration obligations, including a QR code pointing at the guidance. Two clauses, routinely quoted as one. A plug-in device is, by design, portable — it comes off the balcony when you move, when you replace it, or when you simply decide the balcony looks better without it.
So the deregistration duty is live in a way it never really was for panels bolted to a roof. SPEN is one of the operators that has already published the form for it — Northern Powergrid publishes an equivalent, as “G98 Form D — Application to decommission microgeneration”. Others handle decommissioning by email. Keep Form D with your acknowledgement.
Can SPEN object?
SPEN gives the most direct published answer of any of the six:
“We will not normally object to the connection, subject to compliance with G98 and all legislative requirements.”
That is more useful than the flat “a DNO cannot refuse a G98” you will read elsewhere, which we have never been able to verify as an absolute. SPEN’s wording is a normal-course expectation with a condition attached, and the condition is the interesting part: compliance with G98 and with all legislative requirements.
Note what SPEN is not claiming. It does not assert an unlimited authority to decide, and it does not promise approval either. It says it will not normally object provided the technical requirements are met — which is a fair description of how a notification regime is supposed to work, and a more honest answer than most operators give. A grid connection for a device that meets the standard is not a favour being granted.
Which points at the real gate, and it is not the operator.
Compliance is decided before the form
The obligation, and what is still being built
The obligation is not in doubt and SPEN cites the instrument for it — the Electricity Safety, Quality and Continuity Regulations 2002. What is still being developed is a simplified registration pathway for plug-in solar. That pathway is the unfinished thing; the duty is not.
Two more points. G98 is a Great Britain document — Northern Ireland uses G98/NI, and both SPEN areas are in Great Britain. And whatever your circuit count, the operative limit is one device per household, because IPS version 2 permits one per final circuit while Engineering Recommendation G98 Issue 2 Amendment 1 2026 restricts it to one per household unless and until that is amended.
On the form itself, two boxes to get right: registered capacity is the microinverter’s AC output, so 0.8 kW or lower for any compliant device, not the panel wattage; and energy storage capacity is zero, because storage within the device is not permitted on this route. The field-by-field walkthrough covers the rest.
Frequently asked questions
How do I get a G98 certificate from SP Energy Networks?
There is no certificate. You submit Form B and keep whatever acknowledgement comes back — that is the record people mean when they ask for one.
Is SP Energy Networks the same as ScottishPower?
Same corporate group, different regulated businesses. SP Energy Networks owns and operates the wires; ScottishPower sells electricity. Your supplier has no bearing on who your network operator is.
What is a G98 connection?
A notification rather than a permission. G98 covers generation up to 16 A per phase — around 3.68 kW single phase — and connecting under it means telling SPEN what is connected.
What does a G98 form look like?
Form B is a two-page Word document, and it is more installer-shaped than most people expect. It has Customer Details with a customer signature; a full Installer Detailsblock including Accreditation / Qualification and an installer signature; the site address, MPAN, Location within the Customer’s Installation and Location of Lockable Isolation Switch; a capacity table with energy source and technology codes, the manufacturer’s reference number, registered capacity in kW and energy storage capacity; and a declaration headed “to be completed by Installer”. SPEN also publishes single-premises guides alongside it.
Can I submit a G98 to SP Energy Networks myself?
Nothing SPEN publishes restricts notification to installers, unlike some operators. The complication is the attachments — specifically the SSEG test report, which assumes a commissioning engineer. Ask SPEN how it wants a factory-assembled device handled.
What is an export MPAN and where do I find it?
A separate meter point number used for electricity you generate and send to the electricity grid, arranged by your electricity supplier rather than by SPEN, and only relevant if you are pursuing an export tariff. For an 800 VA device, self-consumption matters far more than export.
What is the difference between G98 and G99?
G98 covers up to 16A per phase and is a notification. G99 is for anything larger and is a formal application for connection with an engineering assessment attached. A plug-in solar device at 3.5 A will never approach the boundary.
Is a plug-in device a suitable renewable energy solution for a flat?
It is one of very few that are. For a leaseholder or tenant who cannot put panels on a roof, a plug-in device is a low-carbon option that does not need structural work — which is exactly the gap the legalisation was meant to fill. Whether it suits your flat depends on orientation, shading and daytime consumption rather than on the notification process. Our balcony solar savings guide sets out what to expect.
Does the device need a battery to be worth it?
No, and it cannot have one on this route. A battery would ensure more of what you generate gets used, which is why battery-integrated products are popular — but those meet the definition of a different product class entirely and take the conventional installation route.
For the standard itself rather than SPEN’s handling of it, see our G98 and DNO notification explainer and the shorter balcony solar G98 notification guide. On what has to be verified before any of this applies, see our certified plug-in solar kits tracker and balcony solar electrical safety.