Solar Savvy: Inverter Sizing for Off-Grid Success

Figuring out the right size for an off-grid solar system’s inverter is a breeze when we take a leaf out of the utilities’ book for grid-connected digs. Most pads are hitched to the grid with a 40A breaker, which translates to about 10kW. Sometimes, a 40A breaker can juggle up to 60A for a bit, pushing it close to 16kW. But, according to the Powercor data, most homes hardly ever hit a max demand of 6kW. So, here’s our game plan: we always kit out any standard home with at least two 6kW inverters, and that sorts the demand no sweat. We’ve successfully installed a lot of off-grid systems around Ballarat with this approach and never got it wrong.

Now, sure, some homes might need a bit more juice, maybe even a 3-phase system and a beefier surge capacity. But, no worries, that’s all sorted with a few sums, and we can either go for a bigger inverter or bring in soft-start tech for motors. These days, modern homes are all kitted out with nifty gizmos like soft start or variable speed drives for motors, so the whole surge capacity drama is pretty much old hat. We’re living in the 21st century, after all, with all this cool tech at our fingertips to handle our electrical needs.