How Many Solar Panels Do I Need for My Home?

There is no universal answer to the question, “How many solar panels do I need?” The right number depends on your home's electricity consumption, available roof space and the power output of the solar panels you choose.

Start with your electricity usage. Your electricity bill is a good starting point. Look at your annual electricity consumption in kilowatt-hours, or kWh. You should also consider when you use electricity. For example, a household that uses a large amount of electricity during the day may be able to use more of the solar power as it is generated.

What size are solar panels? Modern solar panels vary in power output. This means that the number of panels required for a particular system size can vary. A higher-output panel may allow you to achieve a particular system capacity using fewer panels.

What else affects system size? Roof space — you need enough suitable space to install the required panels. Roof orientation — the direction of the panels can affect electricity generation. Shading — trees, chimneys and neighbouring buildings can reduce solar production. And your future electricity needs: think about buying an electric vehicle, installing a heat pump, increasing the size of your home, or changes in household occupancy. Planning ahead may influence the system you choose today.

Should you install as many panels as possible? Not always. SEAI advises that solar PV systems should be designed with the property's electricity demand in mind. The objective is not simply to cover every available area of roof with panels, but to create a system that makes sense for your energy needs. (Sustainable Energy Authority of Ireland)

The best approach: before choosing a system, assess your annual electricity consumption, daytime electricity usage, available roof area, shading, panel specifications, budget, and future energy requirements.

AMPM Solar can help customers and trade partners source solar panels and equipment suitable for projects of different sizes. Contact us to discuss the right solar equipment for your home or project.