What Is a DNO? Supplier vs Network for Solar in Scotland

What is a DNO? It is your distribution network operator: the company that owns and runs the cables, poles and substations carrying electricity from the national grid to your home. It is not the company that bills you. That is your energy supplier, which you can change, while your DNO is set by your address. In Central and Southern Scotland, including Livingston, Edinburgh and Glasgow, it is SP Energy Networks; north of the Central Belt it is SSEN.

This guide is for Scottish homeowners adding solar panels, a battery or a heat pump: who does what, in what order, and which jobs are yours.

What a DNO does, and what your supplier does

Great Britain has 14 electricity distribution licence areas, each run by a licensed network operator. Network operators connect homes to the grid, can move your electricity meter and fix power cuts that are not caused by a fault inside your property. As SP Energy Networks says, whoever you pay your bill to, it is the company to call for a power cut or a new connection.

Your energy supplier sells you electricity, bills you and is responsible for your meter; Ofgem's guidance sends meter faults and switching to the supplier, and power cuts and connection issues to the network operator.

Some homes are connected to an independent network operator (IDNO) instead; the Energy Networks Association lists IDNOs with distributor IDs of 24 and above.

Which DNO covers your home: SP Energy Networks or SSEN

SP Energy Networks' Scottish area is Central and Southern Scotland; it also runs Merseyside, Cheshire, North Wales and North Shropshire. SSEN covers the north of Scotland and central southern England, serving more than 3.9 million homes and businesses.

The line sits further south than many people expect, and it follows postcodes rather than town names. When we ran postcodes through Octopus Energy's public grid supply point lookup on 6 October 2026, Livingston, Edinburgh, Glasgow, Falkirk, Dunfermline, Kirkcaldy, Hamilton, Alloa, Alva and Tillicoultry came back as SP Energy Networks, as did almost every postcode in Stirling and Bridge of Allan. Dunblane, Doune, Callander, Kinross, Perth and Dundee came back as SSEN, as did much of the countryside west and north of Stirling, such as Kippen, Gargunnock and Aberfoyle, even though it shares Stirling's FK8 and FK9 postcode districts. Dollar sits on the line.

The quickest check is your bill. The 13-digit MPAN core starts with a distributor ID: 18 means SP Energy Networks and 17 means SSEN. Our SP Energy Networks and SSEN pages cover each network's process.

Who is who when you add solar, a battery or a heat pump

• Your installer designs the system, handles the network paperwork, commissions it and issues the MCS certificate.
• The DNO records or approves your connection, creates the export MPAN that lets you be paid, and upgrades your supply if a heat pump or EV charger needs it.
• Your energy supplier sells you electricity and looks after your meter.
• Your SEG supplier pays you for exported electricity under the Smart Export Guarantee. It can be a different company from your electricity supplier, but you can only have one at a time.
• The meter at your grid connection records import and export separately and, for export payments, must take half-hourly readings.
• MCS certifies installers and products, and suppliers ask for your MCS certificate before paying you.
• Ofgem regulates suppliers and network operators but does not handle individual complaints.

Who to contact for what

Before installation: G98 notification or G99 application

Every solar system and home battery must be declared to the DNO; the route depends on inverter output.

• G98 notification covers inverters up to 16A per phase: 3.68kW on a single-phase supply, standard in most homes, or 11.04kW on three-phase. The installer connects the system and notifies the DNO within 28 days of commissioning.
• G99 application covers anything larger and must be approved before installation. Solar plus a battery often takes a home over 16A per phase.

SP Energy Networks runs a fast track for that mix, approving within 10 days solar up to 3.68kW per phase with a battery up to 3.68kW per phase, if total capacity stays within 7.36kW, export is limited to 3.68kW per phase and the system does not generate during a power cut.

A standard G99 takes longer: Ofgem's standards allow 45 working days to quote for a low-voltage generation connection. Where the network is tight, the options are an export limit or reinforcement work, which SSEN for one charges for on G99 connections. If your system needs a G99 application, it goes in before any work starts.

Heat pumps and EV chargers use a separate ENA form. At a new maximum demand of 60A or below, the installer connects and notifies within 28 days; between 60A and 100A they apply first, and the DNO assesses the supply within 10 working days.

If the supply needs work, SP Energy Networks does it free, typically upgrading an older 30A or 60A main fuse to 80A or separating a cable looped with a neighbour's. Its service partner aims to survey within 90 days of receiving the form, and a roadworks permit can add up to 90 days to unlooping. Planning a heat pump installation? Get the form in early.

Installation and commissioning: the paperwork to keep

On Ecoaim's published process, most domestic installs take one to two days on site. Afterwards, keep three documents, because export suppliers ask for them:

• The MCS certificate, which MCS says should arrive within 10 days of commissioning. Check the address and MPAN straight away: corrections go back through your installer, and the evidence MCS asks for is a full two-page electricity bill showing the MPAN.
• The DNO paperwork. E.ON Next notes that SP Energy Networks does not provide approval letters, so it accepts a copy of the G98 or G99 form instead.
• A line or schematic diagram, which E.ON Next and OVO ask for if you have a battery.

In SP Energy Networks areas, E.ON Next's guidance adds that the installer must send the network the G98 or G99 form, MCS certificate and line diagram so it can generate your export MPAN, and that E.ON Next cannot request it on your behalf.

After installation: export MPAN, smart meter and getting paid

Your existing MPAN is your import number. Getting paid for export needs a separate export MPAN, created by the DNO. Octopus says this takes one to four weeks; E.ON Next quotes two to four and ScottishPower one to two. SSEN does not require an export MPAN under 30kW, so in its area you request one through your export supplier.

Your smart meter must send half-hourly export readings. Octopus says almost all SMETS2 and most SMETS1 meters can; if yours is not communicating, get your supplier to fix it first.

Then choose an export tariff; the best rates usually need you to buy electricity from the same company. Our guide to Smart Export Guarantee rates compares suppliers' offers, and our Octopus Flux guide covers time-of-use export for battery homes. Apply promptly: ScottishPower, for one, pays new applicants from the date they applied.

A realistic timeline, step by step

What you do, and what your installer does

Your installer should handle the network side: G98 or G99, the heat pump or EV charger form, commissioning, the MCS certificate and, in SP Energy Networks areas, the paperwork for your export MPAN. At Ecoaim, our in-house team and vetted MCS-certified trade partners submit to SP Energy Networks or SSEN, so there is no DNO paperwork on your side.

Your jobs:

• Give your installer your MPAN at survey stage.
• Make sure your smart meter is fitted and communicating.
• Choose your export tariff and apply.
• Send export readings if asked; ScottishPower needs them online every six months or it cannot pay you.

What to tell your energy supplier

The formal notification goes to the DNO through your installer. Your supplier still needs to hear from you to get your meter recording export, to set up an export tariff if it will pay you, and to confirm your electricity tariff suits the export deal you want. E.ON Next's Export Exclusive, for example, is not available alongside time-of-use tariffs such as Next Drive, and Octopus pairs Outgoing Octopus only with certain import tariffs.

If you add a battery later, tell your export supplier. Ofgem lets suppliers decide whether to pay for export from a battery charged from the grid, and Octopus and OVO say in their terms they are not obliged to. Our page on solar panels with battery storage covers how the two work together.

Switching supplier when you have solar or a battery

You can switch your electricity and export tariff separately, and the export MPAN stays with the property; British Gas, for example, collects it from your old export supplier.

Watch tied tariffs. Moving your electricity supply can end an export deal or cut its rate: EDF's Export 12m ends if you move your supply elsewhere, and OVO drops you to its standard SEG rate if you stop qualifying. Compare import options in our guide to the best tariffs for solar and battery homes.

Power cuts are the DNO's job, not your supplier's

Call 105 in a power cut: it is free across Great Britain and connects you to your network operator. SP Energy Networks also lists 0800 092 9290 for Central and Southern Scotland.

Your solar panels will switch off too. UK Power Networks explains that solar systems shut down automatically in a power cut so they cannot feed lines engineers are working on, and usually restart about 20 seconds after power returns. A battery also shuts down unless it was designed and installed for backup, or island, mode. If anyone at home has additional needs, the free Priority Services Register is available through your network operator or supplier.

Common delays and how to avoid them

• Mismatched details on the MCS certificate: check it the day it arrives.
• No export MPAN in SP Energy Networks areas: confirm your installer has sent the form, certificate and diagram.
• A meter that cannot send export readings: fix it before you apply.
• Supply upgrades for heat pumps and EV chargers: submit the ENA form early.

Want one team to handle the network side? See how our solar panel installation in Scotland works, or Get your free quote.