| Expected output (PVGIS) | 918 kWh a year per 1 kWp, Belfast, 35 degree pitch, south-facing, 14% losses |
|---|---|
| Distribution network | NIE Networks (Northern Ireland Electricity Networks Limited) |
| Small systems (G98/NI) | Up to 3.68 kW single phase, or under 16 A per phase; Fit and Inform, installer submits within 30 days of commissioning |
| Roof panels | Class A: no more than 20 cm beyond a road-facing roof slope; not above the ridge or 1.5 m above a flat roof |
| Smart Export Guarantee | Installations must be in Great Britain, so Northern Ireland homes are outside it |
What a Northern Ireland roof can produce
The European Commission’s PVGIS tool gives a neutral benchmark because anyone can repeat it. For Belfast, with a 35 degree pitch, south-facing panels and 14% system losses, it returns about 918 kWh a year for each 1 kWp. On the same inputs, central London gets about 1,025 kWh.
That makes payback a tighter question than in the south of England, because each kWp produces fewer units. However, the benchmark is a tool for testing claims, not a forecast for your roof. Ask every installer for its expected annual kWh and the inputs behind it.
Export pay works differently here, so ask about storage, because a battery can change how much you export. Our guide on whether a solar battery is worth it sets out the questions to ask.
Export: no Smart Export Guarantee
Ofgem says Smart Export Guarantee installations must be located in Great Britain. Northern Ireland sits outside it, so a seller who quotes SEG rates to a Belfast home is wrong. Our smart export guide explains the Great Britain scheme so you can spot the difference.
Northern Ireland works through suppliers instead. The details sit in a regulator note rather than a national scheme. A Utility Regulator information note says that to be paid for export electricity you must enter into a contract with a licensed supplier or another buyer. It adds that Power NI must offer terms, which the regulator has approved. Other suppliers’ terms are not subject to that approval.
The note appears to date from June 2016, so check the current terms. Compare offers before you sign, because the rates and conditions can differ.
Funding in Northern Ireland
The Northern Ireland Renewables Obligation was an older support scheme for renewable electricity. The Department for the Economy says it closed to all other technologies on 31 March 2017. It is now closed to all new renewable electricity generation. Projects already accredited keep receiving certificates for 20 years from accreditation or until 31 March 2037, whichever comes first.
We found no current domestic solar grant on the official pages we checked, although schemes can change. So ask any seller who claims “free” or grant-funded panels to name the scheme and show you its official page. The grants and VAT guide covers the UK-wide position.
Connecting to NIE Networks
NIE Networks runs the distribution network, so it is the body your installer must notify. Its G98/NI rules apply when you connect equipment such as solar panels and export power. They cover micro-scale systems of up to 3.68 kW on single phase, under 11.04 kW on three-phase, or under 16 amps per phase. Above those limits, G99/NI applies.
G98/NI uses a Fit and Inform process. Your installer fits and commissions the system. It then has 30 days from commissioning to submit the Stage 1 commissioning form. A Stage 2 application applies when there are multiple installations at one site, and NIE Networks must assess it first.
NIE Networks says G99/NI is not Fit and Inform, so approval must come before installation. Its Fast Track parameters changed on 1 May 2026, so ask your installer which route they used. Our guide to G98 and G99 applications explains the two routes in plain English.
Planning rules in Northern Ireland
Northern Ireland has its own order, the Planning (General Permitted Development) Order (Northern Ireland) 2015. It differs from the rules in England, Scotland and Wales. A 2023 amendment replaced the heat pump classes in the same Part. Check the current text with your council, since the wording below follows the order as made.
Class A covers roofs. Panels must not protrude more than 20 centimetres beyond a roof slope that faces a road and is visible from it. They must not exceed the highest ridge, or 1.5 metres above a flat roof, and they cannot extend beyond the roof edge. In a conservation area or World Heritage Site, a road-facing slope is excluded, and so is a visible flat-roof installation.
Class B covers walls, with its own limits. The order also requires the panels’ primary purpose to be energy for use within the home’s curtilage. For a listed building’s curtilage, you need listed building consent first.
Resale and batteries
Panels can affect a sale, since a buyer inherits the system. Read our note on selling a house with solar panels before you agree to finance that stays with the property.
Export income differs here, so a battery can change the sums. See our guide to adding a battery to existing solar panels if you already own a system.
Comparing your quotes
Use the quote comparison checklist to match scope, equipment and warranties. Prices vary, so get written quotes, because totals can hide different scope.
Wales and Scotland handle planning and funding differently, for example through Nest and Home Energy Scotland. See what Welsh households can claim and how Scottish rules and Home Energy Scotland differ if you own property there.
When you are ready, the free enquiry form can match you with MCS-certified installers.