Are Solar Panels Worth It in Northern Ireland? The 2026 Numbers

I run the solar tracker on this site, which has modelled a day’s solar generation in seven Northern Ireland towns, from the weather recorded that day, every day since late January 2026. So when someone asks whether panels are worth it here, I can answer with what 2026’s weather would have produced in Belfast, Derry, Enniskillen and the rest, rather than a Great Britain average. I also read every quote request that comes through this site, 394 of them between 12 March and 22 September 2026, and this is the question underneath most of them.

Every figure below was checked on 23 September 2026, and the savings were recalculated on 1 October 2026 at the new Power NI export rate.

The short answer

Yes, for most owner-occupied houses in Northern Ireland with a roof that faces roughly south, east or west and is not in heavy shade. A 4kW system makes about 3,330 kWh a year and saves about £714 a year at 33.1p per unit, which pays back a £7,000 install in about 10 years. At the unit rates people in NI actually pay, 32.10p to 38.81p, the saving is £699 to £799 and the payback 7.5 to 11.5 years. A 6kW system saves about £1,071 at 33.1p and pays back in about 9 years. Panels carry 25 to 30 year warranties, so there are a good number of years after payback.

The shortest paybacks you will see quoted pair the cheapest install with the dearest tariff. That is the best case, not the typical one, and I would rather you heard that from me than found out from your inverter app. The cases where the answer is no are further down, and they are specific.

How much a system generates here: the 2026 tracker

The tracker takes the solar radiation recorded each day for Armagh, Ballymena, Belfast, Derry, Enniskillen, Lisburn and Newry (from Open-Meteo), and works out what a 4kW and a 6kW system would have produced from it. The method, and what the numbers are not, is set out on the 2026 generation page. Here is the seven-town average for a 4kW system, as the tracker models it on a flat reference plane. It shows the shape of the year; the next section turns it into a figure for a real roof.

Month (2026)	Average per day, 4kW	Month total, 4kW
February	3.06 kWh	86 kWh
March	6.49 kWh	201 kWh
April	11.01 kWh	330 kWh
May	13.03 kWh	404 kWh
June	11.89 kWh	357 kWh
July	14.74 kWh	457 kWh
August	9.14 kWh	283 kWh
September (1 to 22)	6.57 kWh	145 kWh (22 days)
Modelled, 1 Feb to 22 Sep		2,263 kWh

The towns ranged from 2,138 kWh (Derry) to 2,409 kWh (Newry) over the same period, so where you are in NI matters far less than which way your roof faces.

From the tracker to your roof

The tracker models output on a flat reference plane, because that is what the weather feed provides, and your panels will not be flat. So this page uses the tilt-corrected figures from the site’s system sizes guide: the European Commission’s PVGIS long-term figure for a 30 to 35 degree south-facing pitch in Belfast, cross-checked against the tracker’s Belfast output scaled to a full year. That gives about 3,330 kWh a year for a 4kW system and about 5,000 kWh for 6kW. If your roof faces east or west, expect less.

Payback: the site’s base case, then three real NI unit rates

The base case is the one the sizes guide uses, so the site agrees with itself. Installed prices are £6,000 to £8,000 for 4kW and £8,000 to £12,000 for 6kW, with 0% VAT (the same ranges as the cost guide). It also matches our solar calculator: 45% of the generation is used in the house, units used in the house are valued at 33.1p (the midpoint of Power NI’s 32.10p to 34.15p from 1 July 2026), and exported units at 11.88p (Power NI’s rate from 1 October 2026 to 30 September 2027). A 6kW household that is out all day will use a smaller share than a 4kW one, so treat the 6kW rows as the better case.

System	Annual generation	Annual saving at 33.1p	Simple payback at the mid-price
4kW (£6,000 to £8,000)	3,330 kWh	£714	about 10 years
6kW (£8,000 to £12,000)	5,000 kWh	£1,071	about 9 years

Your own unit rate will not be exactly 33.1p, so here is the same generation and self-use split at three real unit rates, checked on 23 September 2026:

• 32.10p: Power NI monthly direct debit with online billing, the lowest annual cost on the Consumer Council’s comparison table (prices for 22 September 2026, including VAT).
• 35.99p: Share Energy from 1 October 2026, after its 12.6% rise.
• 38.808p: Click Energy’s standard rate, its only domestic rate since it withdrew its discounted tariffs.

System	Unit rate	Saving a year	Payback at the low price	Payback at the high price
4kW (£6,000 to £8,000)	32.10p	£699	8.6 years	11.5 years
4kW	35.99p	£757	7.9 years	10.6 years
4kW	38.808p	£799	7.5 years	10.0 years
6kW (£8,000 to £12,000)	32.10p	£1,048	7.6 years	11.5 years
6kW	35.99p	£1,135	7.0 years	10.6 years
6kW	38.808p	£1,199	6.7 years	10.0 years

Export stays at 11.88p in every row. That is what Power NI pays for the year 1 October 2026 to 30 September 2027 (up from 9.64p), and it publishes a new rate towards the end of each September, so check the export payments guide for the current figure.

Two things move those paybacks more than anything else. The first is price: the difference between a £6,000 and an £8,000 install on the same 4kW system is about three years at 32.10p. The second is how much of the power you use yourself. The export rate matters much less: every extra penny on export is worth about £18 a year on a 4kW system.

Because the installed price is the biggest lever on your payback, it is worth seeing two or three prices for your own roof. You can compare quotes from MCS-certified NI installers here.

When solar is worth it

The paybacks at the shorter end of the table come from houses where most of these are true:

• You own the house and expect to stay 10 years or more. On the numbers above, that is roughly where the system has paid for itself.
• Somebody is in during the day, or the dishwasher, washing machine and immersion can run in daylight. Every unit you use in the house is worth 32p to 39p; every unit you export is worth single pence.
• The roof faces south, east or west and has little shade. Our roof orientation guide covers east-west splits, which suit homes that use power morning and evening.
• Your bill is £100 a month or more. That is the band 262 of the 394 people who asked for quotes through this site were in.
• You are on a dearer tariff, or expect an EV or heat pump. More use in daylight means a higher share of self-use.

When it is not worth it

These are the cases where I would tell someone to hold off, and the numbers behind them:

• You are likely to move within five years. Even the best row in the table is nearly 7 years. You may get some of it back in the sale price, but I have no NI data showing how much, so I would not count on it.
• The house is empty all day and you do not want a battery or diverter. If only a quarter of the generation is used in the house, a 4kW system saves about £572 a year at 33.1p (£564 to £620 at real tariffs), and payback stretches to 10 to 14 years. Nearly three quarters of that system’s output is then paid at the export rate, which resets every October, so the saving is only as safe as that rate. At that point a battery (see our battery guide) or a diverter has to be part of the plan, not an optional extra.
• Heavy shade for much of the day from trees, a neighbouring building or a hill. Optimisers help with partial shade. They do not rescue a roof that is shaded from late morning.
• The only roof faces north. A north-facing pitch catches much less than a south-facing one, so the paybacks above stretch well out. Get an MCS generation estimate for that specific roof before you spend anything.
• The roof needs replacing within the next 10 years. Lifting and refitting the panels adds cost. Do the roof first.
• You rent. The decision and the savings belong to the owner.

If you heat with oil

This is the part most GB guides leave out. According to NISRA’s 2024/25 figures, 61% of homes in Northern Ireland heat with oil. Solar panels make electricity. On their own they do nothing to the oil tank.

Oil is not cheap at the moment: the Consumer Council’s survey on 17 September 2026 put 900 litres at £1,007.16 on average across NI (the current price is on our oil prices page). The way solar touches that bill is a solar immersion diverter, which sends surplus power into your hot water cylinder instead of exporting it for single pence. From spring to autumn that can heat much of your hot water, which means the boiler fires less often. It does not heat the house. The full comparison is in solar versus oil heating costs.

So if you heat with oil, the savings in the table above still apply to your electricity bill. The diverter is how you get something extra on the oil side, and it also lifts your self-use, which shortens the payback.

What about grants?

No grant is open to most NI households for solar; the only exception is NISEP’s income-limited Toasty Homes scheme (see solar panel grants). It is fully funded for owner-occupiers on a gross income under £28,000 (single) or £35,000 (couple) whose heating is missing, solid fuel, an oil or LPG boiler over 15 years old, or pre-2018 storage heaters, and it can run out before the year ends. The schemes people read about (the Smart Export Guarantee, the Boiler Upgrade Scheme, ECO4, the Warm Homes Plan) are Great Britain only. NI’s own Affordable Warmth Scheme covers insulation and heating for lower-income households and does not pay for solar. The one thing every household here does get on solar is 0% VAT on domestic solar, which runs until 31 March 2027. On a £7,000 install that is £1,400 you would otherwise pay at 20%.

If anyone tells you there is an NI solar grant open to everyone, read our solar panel scams guide before you let them in.

My verdict

On this year’s weather and today’s tariffs, solar is worth it for most NI owner-occupiers who plan to stay, use a fair share of the power at home and pay a fair price for the install. It is about a 10 year payback on a 4kW system at 33.1p, and 7.5 to 11.5 years at the unit rates people in NI actually pay, not the 6 years some adverts promise. It gets better if your tariff rises again.

It is not worth it if you are moving soon, if the house is empty all day and you will not add a battery or diverter, or if the roof is shaded or north-facing. The payback period guide goes into the long-run sums, including the inverter replacement you should budget for: solar panel payback in NI.