Are you wondering what the maximum domestic system size is for your building? Getting the right size for your domestic system can be tricky to figure out. This can be made especially difficult when faced with tons of technical jargon.

The short answer: We typically recommend that the maximum domestic solar PV system size is 4kWp, or 16 standard panels (240W-250W) and takes up around 26m² of the roof area – the equivalent of just under two and a half parking spaces.

The reason we recommend this is that once you install a system larger than this size, the rate you are paid per unit of electricity you generates decreases, often meaning that to obtain the same returns you need to have a 7-8kWp system or more. Many homes do not have this amount of roof space and may only be able to install 5-6kWp.

domestic roof solar system

Difficult with larger domestic systems

Systems greater than 4kWp can also require extra electrical permissions (depending on your existing electrical supply) which can add to the cost of the system if extra electrical components are required or if a local grid upgrade is needed.

However, if you have sufficient roof space and the local grid can handle the extra capacity you will be adding then systems up to 10kWp can be a great option.

Unfortunately, we no longer undertake domestic operations anymore. However, you could contact a local domestic installer.

Having trouble with your domestic PV system? Read our domestic PV system troubleshooting list.