How many solar panels do I need for my home?
Here you’ll find out how to calculate the number of solar panels needed for your property, what factors affect system size, and how Irish households typically benefit from solar installations.
Get offers on solar panel systems now
How many solar panels does a typical home need?
Most Irish homes will need between 6 and 16 solar panels to meet their energy needs. A standard setup for an average semi-detached home is usually 8 panels, which equates to a 3.2 kWp system and covers a good portion of the household’s annual electricity use.
The more electricity you want to generate (and the more space you have), the more panels you’ll likely install.
| System size (kWp) | Number of panels | Suitable for | Annual output (approx.) |
|---|---|---|---|
| 2 kWp | 5–6 panels | Small households, low energy use | ~1,700 kWh |
| 3.2 kWp | 8 panels | Average Irish homes | ~2,800 kWh |
| 4.9 kWp | 12 panels | Larger households | ~4,500 kWh |
What affects how many panels I’ll need?
Several factors can influence the number of solar panels you’ll need:
- Your electricity usage: The more energy your household uses, the more panels you’ll need to cover that consumption. Households with electric heating, home offices, or EV charging points will need larger systems.
- Roof space and orientation: South-facing roofs perform best, but east- or west-facing can also work well in Ireland. A clear, unshaded roof gives you more flexibility with panel numbers and placement.
- Panel efficiency: Higher-efficiency panels generate more power per square metre, meaning you can install fewer panels to achieve the same output — useful if your roof space is limited.
- Budget and goals: Some people aim to fully cover their usage, while others install a smaller system to offset part of their energy bill. Your installer can help find the right balance for you.
Example setups for Irish homes
To give you a clearer idea of what might suit your home, here are some sample setups:
- 3.2 kWp system (8 panels):
Ideal for average households (3–4 people)
Covers around 60–70% of typical electricity usage
Eligible for SEAI grant of €2,184
Estimated cost after grant: around €4,200 - 4.9 kWp system (12 panels):
Suitable for larger families or homes with higher usage
Covers up to 90% of electricity needs
Eligible for SEAI grant of €2,400
Estimated cost after grant: around €5,400
Estimating your energy usage
A good starting point is to check your most recent electricity bills. In Ireland, the average household uses around 4,200 kWh of electricity per year.
If your usage is below that, a smaller system may be enough. If it’s higher — perhaps due to heat pumps, EV chargers, or large appliances — a larger system will be more effective in cutting your bills.
Can I produce more electricity than I use?
Yes, and in some cases it can be beneficial. With the Clean Export Guarantee (CEG) scheme, homeowners in Ireland can earn money by selling excess electricity back to the grid. That said, it’s usually most cost-effective to size your system to match your usage as closely as possible.
Get tailored quotes for your home
The best way to know how many panels you’ll need is to speak with a professional solar installer. They can assess your roof, look at your electricity usage, and provide a custom setup that suits your home and goals.
At Solarpanels.ie, we help you connect with trusted solar suppliers in Ireland. Fill in a quick form and get offers tailored to your home’s needs — compare systems, prices, and panel types with no obligation.
