Solar Panels on a North-Facing Roof in Ireland
A north-facing roof is the one orientation most Irish solar guides wave away with “not recommended”. That is broadly right for a steep roof, but it hides a lot of nuance. Ireland gets more than half its sunlight as diffuse light from an overcast sky, which a north face catches almost as well as a south one. This guide puts numbers on it by roof pitch, shows what a north-facing system costs and saves, and walks through the alternatives an installer will usually suggest first. For the general rules on direction, see our guide to roof orientation and, if your roof runs east to west, our guide to east-west solar panels.
Quick Answer
Solar panels do work on a north-facing roof in Ireland, but they produce roughly 55 to 65% of what the same panels would make on a south-facing roof at a typical 30 to 35 degree pitch. A 10-panel 4.4 kWp system that would generate about 3,900 kWh a year facing south drops to around 2,300 kWh facing north, stretching payback from about 7 years out to 11 to 12 years. Most installers will look first at an east or west face, a garage or extension roof, or a ground mount. A shallow-pitch north roof (under 20 degrees) is the one case where north-facing panels are usually still worth doing.
How much do north-facing solar panels produce in Ireland?
The honest answer is “it depends on the pitch”. A panel lying almost flat does not care much which way the roof faces, because it is looking at the whole sky. As the roof gets steeper, a north face tilts further away from the sun’s path, and in winter, when the sun never climbs above about 14° in Dublin at midday, a steep north slope gets no direct sun at all.
The table below is modelled for an Irish latitude of around 53°N and shows annual yield as a share of an ideal south-facing roof at 30–35°. Real figures for your address come from the PVGIS tool installers use, which accounts for local weather and horizon.
| Roof pitch | South-facing | East or west | North-facing | North verdict |
|---|---|---|---|---|
| 10° | 95% | 89% | 80–85% | Usually fine |
| 20° | 99% | 87% | 70–75% | Workable |
| 30° | 100% | 81% | 60–65% | Marginal |
| 35° | 100% | 78% | 55–60% | Marginal |
| 45° | 98% | 76% | 50–55% | Not recommended |
Most Irish houses have a pitch of 30–45°, which lands a north face in the 50–65% band. That is a big loss, but it is not the 20–30% you would see for a north-facing roof in Spain, because so much of Ireland’s annual sunlight is diffuse light scattered by cloud rather than direct beam. Cloud is, oddly, a north-facing roof’s best friend.
The other thing the annual figure hides is the shape of the year. A north face does respectably from April to September, when the sun is high and rises and sets well north of east and west. From November to February it produces very little, which matters because that is when Irish bills are highest and exported summer surplus is worth less than the winter units you still have to buy.
North-facing vs south-facing: cost, savings and payback
The system costs the same whichever way it points, and the SEAI grant is the same too: it is calculated on the size of the system, not on how much it will generate. What changes is the return. Here is the most common Irish install, a 10-panel 4.4 kWp system, on a typical 30–35° roof facing each way.
| South-facing | North-facing | |
|---|---|---|
| Net cost after grant | €6,500–€7,200 | €6,500–€7,200 |
| Annual generation | ~3,900 kWh | ~2,300 kWh |
| Annual saving (no battery) | ~€991 | ~€584 |
| Simple payback | 6.6–7.3 years | 11.1–12.3 years |
Savings assume 40% self-consumption at 35c per kWh and the rest exported at 19c per kWh under the microgeneration scheme. North-facing generation is modelled at 60% of south.
A 11–12 year payback on panels warrantied for 25–30 years is still a positive return, just a much thinner one. It leaves little margin for an inverter replacement around year 12, or for a spell of lower electricity prices. That is why the usual advice is to exhaust the alternatives below before committing to a north face. See our payback period guide for how these figures move with usage and battery storage.
When north-facing solar still makes sense
The roof is shallow
Under about 20° the orientation penalty shrinks to 15–30%, which is close to an east or west roof. Many bungalows, extensions and dormer roofs fall into this band. If you are not sure of your pitch, an installer can read it from a survey or from the roof plans.
It is the only roof you have
A terraced or semi-detached house whose only pitched roof runs north-south has a south face too. It is the house whose ridge runs east-west with the south face shaded, hipped away or covered in rooflights where a north face becomes the only candidate. Even then, check the alternatives first.
You use a lot of daytime power
The savings table assumes 40% self-consumption. Someone home all day, charging an EV or running a heat pump, can push that to 60–70%, and every unit used directly is worth the full import price rather than the export rate. Higher self-use narrows the gap between a north and south roof.
As the second half of a split
A few panels on a north face alongside a fuller south or east-west array is common on houses short of good roof. With a hybrid inverter or optimisers, the weak string does not drag down the strong one, and the north panels add useful summer output at marginal cost.
Ask your installer for these three things
- A PVGIS yield estimate for each roof face you are considering, not a single site figure.
- A string layout showing north-facing panels on their own string or on optimisers, so partial shade on one face does not throttle the rest.
- A written payback figure based on your own bills, not a national average.
Better options than a north-facing roof
Most homes that think they have a north-facing problem have a south-facing solution hiding somewhere. Work down this list before settling for the north face.
| Option | Typical yield vs south | Notes |
|---|---|---|
| The other side of the same roof | 100% | If your front faces north, your back faces south. Rear roofs are also the usual place for panels anyway. |
| East or west face | 80–85% | Hipped roofs and L-shaped houses often have one. An east-west split spreads output across the day. |
| Garage, shed or extension roof | Depends on facing | Single-storey roofs are often shallower, so even a north-ish one performs better than the main roof. |
| Flat roof with tilt frames | 90–100% | Frames let the installer point panels south at 10–15° regardless of the building. |
| Ground mount | 100% | Best yield and easy to clean, if you have the garden. Up to 25 m² is planning-exempt. |
| North face on tilt frames | Varies | Raising panels on a pitched roof to point them backwards over the ridge is rarely done: it is unsightly, catches wind, and may fall outside the planning exemption. |
Read more in our guides to ground-mounted solar, flat-roof solar and planning permission.
Frequently Asked Questions About North-Facing Solar Panels
Can you put solar panels on a north-facing roof in Ireland?
Yes. Nothing stops an installer fitting panels to a north face, and the SEAI grant is the same. The issue is output: at a typical 30 to 35 degree pitch a north-facing roof produces roughly 55 to 65% of a south-facing one, so payback is much longer. On a shallow roof under 20 degrees the loss is only 15 to 30% and north-facing panels are usually still worth doing.
How much less do north-facing solar panels produce?
It depends on the pitch. Around 15 to 20% less at 10 degrees, 25 to 30% less at 20 degrees, 35 to 45% less at 30 to 35 degrees, and 45 to 50% less at 45 degrees, compared with the same panels facing south. Ireland's high share of diffuse light means the penalty is smaller here than in sunnier countries.
Is a north-facing solar system worth it financially?
Usually only just. A 10-panel 4.4 kWp system that makes about 3,900 kWh a year facing south makes around 2,300 kWh facing north, stretching simple payback to roughly 11 to 12 years against 25 to 30 year panel warranties. It is a positive return but a thin one, so most installers will suggest an east or west face, an outbuilding roof or a ground mount first.
Do north-facing solar panels work in winter?
Barely, on a steep roof. In December the midday sun is only about 14 degrees above the horizon in Dublin, so a north slope of 30 degrees or more sees no direct sun and runs on diffuse light alone. From April to September the sun rises and sets well north of east and west and climbs high at midday, so north-facing panels do reasonably well in summer.
Does the SEAI grant depend on which way the roof faces?
No. The SEAI Solar Electricity Grant is calculated on the size of the system in kWp, up to a maximum of €1,800 for the most common 4.4 kWp install, regardless of orientation. The installer must still be SEAI-registered and the house built and occupied before 2021.
Should I put panels on both the north and south side of my roof?
It can make sense if the south face is short of space. With a hybrid inverter that has separate inputs, or with optimisers, the north panels sit on their own string so they do not drag down the south ones. They add useful summer output at a low marginal cost, but the south face should always be filled first.
Related Guides
Ground Mounted Solar Panels
Costs, planning permission, pros & cons vs roof-mounted, and space requirements.
Solar for Flat Roofs
Ballasted mounting, tilt, wind load and planning for flat roofs.
Solar Payback Period
How long solar takes to pay back in Ireland, with a worked example.
Are Solar Panels Worth It?
Honest pros, cons, and payback analysis for Irish homes.
Sources
- European Commission JRC: PVGIS Photovoltaic Geographical Information System (yield by orientation and tilt), re.jrc.ec.europa.eu
- SEAI: Solar Electricity Grant, seai.ie
- Met Éireann: Sunshine and solar radiation climate data for Ireland, met.ie
Last updated: September 2026
Fact-checked by John Rooney, Solar Energy Editor. Editorial policy
John Rooney is the editor of Solar Info and has been covering the Irish solar energy market since 2023. He fact-checks all content against official SEAI data and maintains relationships with SEAI-registered installers across Ireland.
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