The Complete Homeowner’s Guide to Going Solar in Ireland

Switching to solar power is one of the smartest moves you can make, for your home, your wallet, and the planet. But where do you begin? With so many panels, batteries, and buzzwords flying around, it can feel a bit overwhelming.

That’s where this guide comes in.

We’ve broken down everything you need to know before going solar, from understanding your electricity bill to choosing the right equipment, without the jargon or sales fluff. Whether you're planning a full home solar setup or just curious about what's involved, this step-by-step walkthrough will help you make confident, informed decisions.

Start with Your Electricity Bill

Before you even think about solar panels, the smartest first step is to grab your electricity bill and really look at it. Why? Because your bill tells the story of how your home uses energy, and that story determines everything from system size to savings.

Start by finding your monthly kilowatt-hour (kWh) usage. Most bills show your consumption over the past year. Take note of the average. This figure helps size your solar system so it can meet your actual needs. Using more electricity? You’ll likely need a bigger system. Lower usage? You might get away with something smaller and more cost-effective.

Next, pay attention to when you use electricity. If you’re on a day/night meter, is most of your usage during daylight hours? That’s perfect, solar energy will directly power your home. But if your usage leans toward the evening, you might want to factor in battery storage to store your solar energy for nighttime use.

Look at the cost breakdown too, unit rates vs. standing charges. Solar will reduce your unit usage, but standing charges (the daily cost of being connected) will still apply. It’s important to know what part of your bill can actually be reduced.

Also, take note of seasonal spikes. Do your bills shoot up in winter due to electric heating? These patterns can influence how much energy you’ll want to generate and whether you want to oversize your system or include storage.

Lastly, check what kind of tariff you’re on. If you're eligible for smart export payments or time-of-use rates, your solar system could actually earn you credit by exporting excess energy back to the grid.

So don’t skip this step your electricity bill is more than just a statement. It’s the foundation of a well-planned, cost-effective solar setup.

Evaluate Your Roof Space

Right alongside checking your electricity bill, assessing your roof is the other key starting point. After all, no matter how much energy you use, if you don't have the space to fit enough panels or if the sun can’t reach them properly, you're limited from the get-go.

Start by looking at how much usable space you actually have. A clear, unshaded roof area facing south is ideal in Ireland for maximum generation. But east or west-facing roofs can also work well, especially with the right system design. North-facing? That’s usually less productive and may not justify the investment without a hybrid approach.

Ask yourself: how many panels can I realistically fit? A typical solar panel is about 1.7m x 1m, and a solid 4kWp system might need 8–10 panels around 15–20 square metres of space. Things like dormers, chimneys, vents, or even satellite dishes can eat into that available area.

Also watch out for shade. Trees, buildings, and chimneys can seriously impact performance, especially during peak solar hours. If your roof has some shading, clever system design (like using optimisers or microinverters) can help, but it’s still something to factor in early.

Ultimately, your roof’s size, orientation, and sunlight exposure are what determine what’s possible and what’s worth doing. Once you know how much space you’ve got and how much sun it gets, everything else from panel type to system size starts to fall into place.

Do Your Homework on the Panels Themselves

Once you've assessed your energy needs and roof space, it's time to focus on the panels themselves the core of your solar investment. While many panels may look similar, what's underneath the glass matters.

Start with Tier ratings. Most homeowners should stick with Tier 1 panels, which come from established, bankable manufacturers with proven quality control, R&D investment, and long-term reliability. These panels are tested to international standards and built to perform, so you’re already in good hands.

Within Tier 1, differences in efficiency are relatively small, but still worth noting. Today’s high-performance panels typically range between 20.5% and 24% efficiency. While the jump from 21% to 22.5% may seem minor, it can mean significantly more generation over 25+ years — especially if space is limited.

Equally important is wattage output. Most modern panels installed in Ireland now fall in the 430W to 500W range, with commercial-grade or larger-format residential panels reaching up to 550W or even 645W. Higher-watt panels allow you to hit your generation target with fewer units, ideal if roof space is limited or you want to minimise mounting gear.

Don't forget to check the warranties:

• A good product warranty should cover 15 to 30 years.
• A strong performance warranty will guarantee at least 85–90% output after 30 years, a sign of real confidence from the manufacturer.

Lastly, weigh up the cost per watt. This lets you compare value across brands and wattages. Sometimes a slightly pricier panel offers much better long-term performance, reliability, and warranty coverage — and that’s what gives real return on investment.

System Sizing & Inverter Choice — Get the Core Right

Once you've wrapped your head around your usage and chosen your panels, it's time to size the system properly and pick the right inverter to bring it all together.

System size is usually measured in kilowatts peak (kWp), which refers to the total combined output of your panels under ideal conditions. A typical Irish home might need anywhere from 3kWp to 6kWp, depending on how much electricity you use, how much roof space you have, and how far you want to go in reducing your electricity bill.

It’s not always about covering 100% of your usage. Some homeowners aim to offset just daytime loads, while others go bigger especially if they plan to add a battery, an EV, or a heat pump in the near future. Oversizing slightly can future-proof your setup without adding huge cost.

Then comes the inverter, the unsung hero of your solar system. It converts the direct current (DC) from your panels into alternating current (AC) that your home can use. The type of inverter you choose depends on your setup and goals:

• String inverters are the most common and cost-effective for systems with good sun exposure and minimal shading.
• Hybrid inverters allow you to connect batteries, ideal if you're planning to store energy for night-time use or future energy independence. (I would recommend this option even if you don’t plan on adding battery storage from the get go)
• Microinverters or power optimisers are great for roofs with partial shading, multiple orientations, or complex layouts. They allow each panel to perform independently, squeezing more energy out of tricky installs.

System Sizing & Inverter Choice — Match Output with Capability

Sizing your solar system isn’t just about how many panels you can squeeze onto the roof, it’s also about making sure the inverter can handle that power efficiently. This is where the concept of inverter oversizing comes in.

Let’s say your roof has room for 28 panels — that could add up to 12-14kWp, depending on the wattage per panel. But that doesn’t mean your inverter has to be rated for the full 14kW. Most manufacturers actually allow you to oversize your solar array beyond the inverter's rated capacity, and this is not only allowed, it’s often smart design.

Depending on the brand and model, inverters can accept between 125% and 200% oversizing. For example, a 5kW inverter might legally and safely support up to 6.25kWp or even 7.5kWp of panels, depending on its spec. This is especially useful in Ireland, where solar production rarely hits peak conditions so oversizing lets you maximise generation during real-world conditions, like cloud cover or low winter sun.

The benefits?

• You generate more electricity across the day
• You get more bang for your buck from your inverter
• You make full use of your available roof space

But it’s all about balance. Too much oversizing on the wrong inverter could lead to clipping (lost production during peak sun hours). That’s why it’s critical to match your panel array and inverter spec carefully.

Battery Storage: Optional, But Increasingly Valuable

We touched on battery storage earlier, but it’s worth expanding on because while technically optional, a battery can add serious flexibility and value to your solar setup.

At its core, a battery stores the excess energy your panels generate during the day, so you can use it later when the sun’s gone down. But that’s just the start.

With a smart inverter and a time-of-use tariff, you can also charge your battery overnight during low-cost electricity windows, like the EV or night rate. Then during the day, your solar power can be exported to the grid at a higher rate or used to run the house if rates are high. This kind of setup can dramatically increase your energy savings and even generate some return via export payments.

In short, you’re not just storing your own solar you’re using your battery as a smart energy manager, shifting power in and out based on pricing and usage.

When choosing a battery, look at:

• Capacity (measured in kWh) match it to your night-time usage.
• Cycle life how many charge/discharge cycles it will handle before degrading.
• Warranty most quality batteries offer 10 years or a minimum guaranteed cycle count.

Battery Compatibility Matters

While batteries offer fantastic benefits, it’s important to understand that you can’t just pick any battery and plug it in. Your inverter manufacturer determines which batteries are compatible, and getting this wrong can lead to communication issues, reduced performance, or even warranty problems.

For example, Solis hybrid inverters typically support batteries like Dyness and Pylontech. Huawei inverters, however, require a Huawei Luna battery. Third-party batteries won’t work. Other brands such as Sungrow or Growatt also have specific battery pairings that work best.

Even within compatible brands, you need to match the correct battery model and voltage range supported by your inverter. Some combinations might physically connect but won’t function properly unless they’re fully approved.

It’s always best to check the compatibility list from the inverter manufacturer and confirm with your installer. A properly matched inverter and battery setup ensures better performance, safer operation, and full warranty support.

 

Switching to solar isn’t just about picking panels — it’s about designing a system that suits your home, your lifestyle, and your future energy needs.

From analysing your electricity bill to evaluating your roof space, selecting quality panels, matching the right inverter, and considering battery storage — every decision plays a part in how much you’ll save, how flexible your system will be, and how long it’ll serve you.

The good news? You don’t have to figure it all out alone.

At Solarboss.ie, we’re here to help you cut through the jargon, avoid costly mistakes, and get a solar setup that’s smart, efficient, and built to last. Whether you’re ready to go or just weighing your options, we’re happy to chat.