Solar Oversizing Explained

We wanted to quickly cover something which we do often with our installs, but is rarely explained properly to potential Solar PV owners. If you have seen a Solar PV Quotation, you probably noticed that the Solar Panels peak output is more than the inverter. Sometimes by quite a margin. Why is this?

This is called Oversizing, while it sounds counterintuitive, it's actually a great idea. Solar panels rarely operate at their absolute peak power, typically only in the Summer, and at times of the day where the sun is at the perfect angle. So by having more panels, you can increase the output when not at 100%. As when operating at 75% of their peak output, the output figure will be larger with 6kWp of panels, rather than 4kWp.
The graph below shows that while you lose out at the very peak, for the rest of the day you will always outperform the smaller array, meaning you have more usable power when you actually need it.

Graph showing the difference between having the panels with the same peak output as the inverter, and with them having a 25% oversizing.

It's a neat trick to get more bang for your buck. But remember, it's not a one-size-fits-all solution. It needs careful calculation and understanding of your specific energy needs and site conditions. And that's where Solr comes in. We're always here to help you make sense of the solar jargon and make the best decisions for your renewable energy journey. Give us a shout, and let's get you powered up!