Solar Panels NI: Your Complete Guide to Going Solar in Northern Ireland

If you’ve been thinking about getting solar panels fitted, you’re probably wondering whether they’re actually worth it here in Northern Ireland. Fair enough. We don’t exactly have a reputation for glorious sunshine, and nobody wants to spend thousands of pounds on something that might not deliver.

Here’s what most solar companies won’t tell you straight away: solar panels in NI generate less electricity than those down south or in continental Europe. But they still generate plenty. A typical 4kW system here produces between 3,200kWh and 3,800kWh annually. That’s enough to slash your electricity bills by £400 to £900 per year, depending on your usage patterns and system size.

The real question isn’t whether solar panels work in Northern Ireland. They do. The question is whether they make financial sense for your specific situation, and how to avoid paying over the odds when you do decide to go ahead.

What solar panels actually cost in NI right now

Let’s cut through the vague pricing you’ll find on most websites. Here’s what you’ll genuinely pay for a fully installed system in Northern Ireland in 2026:

3kW system (8-9 panels)

• Cost: £5,500 to £7,000
• Suits: 1-2 person households, smaller properties
• Annual generation: 2,400 to 2,900kWh

4kW system (10-12 panels)

• Cost: £6,500 to £8,500
• Suits: Average 3-bed semi-detached homes
• Annual generation: 3,200 to 3,800kWh

6kW system (14-16 panels)

• Cost: £8,500 to £11,000
• Suits: Larger families, detached properties
• Annual generation: 4,800 to 5,700kWh

These prices include everything: panels, inverter, mounting equipment, scaffolding, electrical connection, and all the paperwork. They also reflect the 0% VAT that’s currently applied to residential solar installations in NI, which saves you roughly £1,000 to £1,800 compared to what you’d have paid a few years back.

If you want a battery as well, add another £2,500 to £4,500 depending on capacity. We’ll cover whether batteries are worth the extra outlay further down.

Why do prices vary so much?

You’ll notice a £2,000 spread even for the same system size. That’s not a typo. The variation comes down to:

• Panel brand (premium manufacturers charge more but offer better efficiency)
• Installer overheads (big companies with showrooms cost more than smaller local firms)
• Roof complexity (awkward access means more scaffolding and labour time)
• Inverter type (microinverters cost more than string inverters)
• Profit margins (some installers simply charge more because they can get away with it)

This last point is exactly why comparing quotes matters so much. We’ve seen homeowners save £800 to £1,200 just by getting multiple quotes and playing them off against each other. That’s money you’d be throwing away by accepting the first price you’re given.

Do solar panels actually work in NI’s weather?

This is the question everyone asks, and understandably so. Northern Ireland averages between 1,000 and 1,200 hours of sunshine annually. Compare that to Cornwall’s 1,800+ hours or Spain’s 2,500+ hours, and you might think we’re at a serious disadvantage.

But here’s what matters: solar panels generate electricity from daylight, not direct sunshine. Even on overcast days—which we have plenty of—your panels keep working. Output drops, yes, but it doesn’t stop.

Modern panels are specifically engineered to capture diffuse light that penetrates cloud cover. On a heavily overcast day, expect around 10% to 25% of peak output. On bright but cloudy days, that jumps to 40% to 60%. And on those rare sunny days we do get, your system will be absolutely hammering it.

Real-world performance data

A 4kW system on a south-facing roof in Belfast typically generates:

• Summer months: 400 to 500kWh per month
• Spring/Autumn: 250 to 350kWh per month
• Winter months: 100 to 180kWh per month

That adds up to 3,200 to 3,800kWh over the full year. The average NI home uses around 3,500 to 4,500kWh annually, so a well-sized system covers the bulk of your electricity needs.

One thing that actually works in our favour: solar panels hate overheating. They lose efficiency when temperatures climb above 25°C. Our cooler climate means panels maintain their efficiency better than they would in hotter regions. Every cloud has a silver lining, quite literally.

Working out whether solar panels make sense for your home

Not every property in NI is ideally suited for solar. Before you start requesting quotes, here’s what to check:

Roof orientation

South-facing roofs perform best, capturing maximum sunlight throughout the day. But east and west-facing roofs work perfectly well too, typically generating 15% to 20% less than south-facing equivalents. You lose production in the morning or afternoon, but gain it at the other end of the day.

North-facing roofs are trickier. Output drops by 40% to 50%, which makes the financial case much weaker. It’s not impossible, but you’d need to run the numbers carefully.

Roof angle

The sweet spot is between 30 and 40 degrees, which matches most pitched roofs here. Flat roofs work too—installers mount panels on angled frames to optimise sun capture.

Shading

This is the big one. Even partial shading from chimneys, trees, or neighbouring buildings can seriously hurt your system’s output. With standard string inverters, shade on one panel drags down the entire string. Microinverters or power optimisers can mitigate this, but they add to the cost.

Any decent installer will conduct a shading analysis during their site survey. If someone quotes you over the phone without seeing your roof, walk away. They’re not taking your installation seriously.

Roof condition

Your panels will sit there for 25 to 30 years, so your roof needs to be in decent nick. If you’re looking at roof repairs in the next decade, get those done first. Removing and reinstalling panels later is expensive hassle you don’t need.

Available space

A typical panel measures about 1.7m by 1m. For a 4kW system, you’ll need roughly 16 to 20 square metres of usable roof space. Most semi-detached and detached homes in NI have enough room, but terraced houses might be tighter.

The honest truth about solar panel savings

You’ll see installers throwing around figures like “save 70% on your bills” or “£1,200 annual savings.” These aren’t lies exactly, but they’re often best-case scenarios that don’t apply to most households.

Here’s a more realistic breakdown:

Without battery storage

If you’re out at work during the day, you’ll use maybe 25% to 35% of what your panels generate directly. The rest gets exported to the grid. You currently get paid around 12p to 15p per kWh for exports through the Smart Export Guarantee, but you’re paying 28p to 32p per kWh to import electricity in the evening.

Typical annual savings: £350 to £550

With battery storage

A battery lets you store daytime generation for evening use. Self-consumption jumps to 60% to 80%, meaning you buy far less from the grid.

Typical annual savings: £550 to £900

If you work from home

You’ll naturally use more electricity during daylight hours—running the kettle, heating lunch, charging devices. Self-consumption without a battery can hit 45% to 55%.

Typical annual savings: £450 to £700

The payback period for most NI installations sits between 9 and 14 years. After that, you’re looking at 15+ years of essentially free electricity, plus whatever you earn from exports.

Grants and financial support for solar panels in NI

Right, let’s address the elephant in the room: there are currently no domestic solar panel grants available in Northern Ireland for most homeowners. The old Renewables Obligation Certificate (ROC) scheme closed to new applicants back in 2017, and nothing has replaced it yet.

What you do get:

0% VAT

Since May 2023, there’s no VAT on residential solar installations in NI. This isn’t a grant as such, but it does knock £1,000 to £1,800 off your final bill. It’s scheduled to run until at least March 2027.

Smart Export Guarantee (SEG)

Electricity suppliers must offer you a tariff for any electricity you export to the grid. Rates vary from 3p to 15p per kWh depending on the supplier. Not huge money, but it adds up.

Business grants (NISEP)

If you’re a business owner, the Northern Ireland Sustainable Energy Programme can cover up to 20% of installation costs. Worth investigating if you run a farm, shop, or commercial premises.

Finance options

Many installers offer 0% or low-interest payment plans, letting you spread the cost over 5 to 10 years. Green loans from some banks carry preferential rates for renewable energy investments too.

The NI Energy Strategy does talk about expanding support for renewables, so grants may appear in future. But nobody’s holding their breath. For now, solar panels need to make financial sense based purely on bill savings and export income.

Choosing solar panel installers in NI

This is where plenty of people come unstuck. The solar installation market has good operators and not-so-good ones, and telling them apart isn’t always easy.

Non-negotiable requirements

Every installer you consider must be MCS certified (Microgeneration Certification Scheme). This ensures they meet quality standards and your installation qualifies for SEG payments. No MCS certification, no dice.

RECC membership (Renewable Energy Consumer Code) is another good sign. It provides additional consumer protection and a proper complaints procedure.

Check for public liability insurance too—minimum £2 million coverage. And ask how long they’ve been trading. Solar is a long-term investment, and you need an installer who’ll still exist when you need warranty support in five or ten years.

Red flags to watch for

• Quotes given over the phone without a site visit
• Pressure to sign immediately with “limited time discounts”
• Promises of unrealistic savings (“eliminate your bill completely!”)
• Vague warranty terms or single-year workmanship guarantees
• No references from previous NI installations
• Unusually cheap prices (they’re cutting corners somewhere)

Questions to ask

• What specific panels and inverter are you proposing?
• What’s the estimated annual generation based on my roof?
• What warranties apply to panels, inverter, and workmanship?
• How many installations have you completed in NI?
• Can I speak with previous customers?
• What happens if my system underperforms expectations?

A good installer will answer all of these openly. If they’re evasive or pushy, find someone else.

Getting the best deal on your solar installation

Here’s the single most important piece of advice: get multiple quotes. At least three, ideally four or five.

When those quotes come in, don’t just look at the bottom line. Compare:

• System size and expected output
• Panel brand and efficiency rating
• Inverter type and warranty length
• What’s included (scaffolding, paperwork, generation meter, etc.)
• Workmanship warranty duration
• Payment terms

Sometimes the cheapest quote uses inferior equipment or skimps on installation quality. Sometimes the most expensive quote is just padding their margins. You want the best overall value, not necessarily the lowest or highest price.

Northern Ireland homeowners who compare quotes properly save an average of £800 on their installations. Some save considerably more. Given that the whole process takes a few weeks of your time, that’s a pretty decent hourly rate.

Battery storage: worth the extra money?

Batteries are the biggest decision after the panels themselves. They add £2,500 to £4,500 to your upfront cost but can significantly boost your savings.

Arguments for getting a battery

If you’re out during the day, a battery is almost essential for maximising self-consumption. Without one, you’re exporting cheap and importing expensive, which isn’t ideal.

Batteries also provide some energy security. During power cuts (which do happen in NI, especially in rural areas), certain battery systems can keep your lights on.

And if electricity prices keep rising—which they probably will—stored solar energy becomes increasingly valuable.

Arguments against

Batteries have shorter lifespans than panels. Most come with 10-year warranties, compared to 25 years for panels. You might need a replacement during your system’s lifetime.

They also add complexity. More equipment means more potential failure points.

And if you’re home during the day or work from home, your self-consumption is already decent without a battery. The extra investment takes longer to pay back.

Our take

For households where everyone’s out during work/school hours, batteries make strong financial sense. For home-based workers or retirees, the case is weaker. Run the numbers for your specific situation, or talk to an installer who can model it properly.

Common concerns answered

Will my roof support the weight?

Almost certainly yes. A typical residential system weighs 250kg to 400kg spread across your entire roof. That’s well within normal structural tolerances for houses in NI. Your installer will verify this during their assessment, but it’s rarely an issue.

Do I need planning permission?

Usually not. Solar panels fall under permitted development in NI, meaning you can install them without formal planning approval. Exceptions include listed buildings, conservation areas, and installations that protrude significantly from your roof plane. Your installer should confirm this before proceeding.

What about maintenance?

Solar panels need surprisingly little upkeep. Rain keeps them reasonably clean, and you might give them a gentle wash once or twice a year if you notice dirt buildup. Inverters sometimes need replacing after 10 to 15 years, but panels themselves just keep working.

Most installers offer optional maintenance contracts, but they’re not essential. Just keep an eye on your system’s output through the monitoring app, and call someone if performance drops noticeably.

Will solar panels affect my house insurance?

Possibly. Some insurers include solar panels under standard contents/buildings cover. Others want a small premium increase (typically £20 to £100 annually). Ring your insurer before installation to check their policy and avoid any nasty surprises.

Can I take panels with me if I move?

Technically yes, but it’s expensive and usually not worth it. Most people leave their panels for the next owner, which can actually increase your selling price. Homes with solar are increasingly attractive to buyers who want lower running costs.

Making your decision

Solar panels in NI are a solid investment for most homeowners with suitable roofs. The technology works fine in our climate, the financial returns are genuine (if not spectacular), and electricity prices aren’t going anywhere but up.

The key is going in with realistic expectations. You won’t eliminate your electricity bill entirely. You won’t see massive returns in the first few years. But over the 25+ year lifespan of your system, you’ll save thousands of pounds while doing something decent for the environment.

What matters most is:

1. Sizing the system correctly for your actual usage
2. Getting multiple quotes to ensure fair pricing
3. Choosing quality equipment and reputable installers
4. Understanding exactly what you’re paying for

We’ve helped over 30,000 Northern Ireland homeowners compare solar panel quotes. The ones who take their time, do proper research, and compare options end up with better systems at lower prices. The ones who rush in or accept the first quote often regret it.

If you’re ready to get quotes from verified installers across NI, start your comparison here. We’ll connect you with MCS-certified companies who’ll visit your property, assess your roof, and provide detailed proposals. You compare them, ask questions, and choose whoever offers the best overall package.

No pressure, no commission for us, just honest comparison. That’s how we think solar should be sold.

Frequently asked questions