Enter how much power you use and where you are. This sizes an array, inverter and battery the way an installer's first pass would, then prices a parts list from the cheapest current offer in the index for each line, with alternatives one click away. It is a starting point for a conversation with a licensed installer, not a design.
Read first. In NZ, connecting an inverter to house wiring or the grid is prescribed electrical work: a licensed electrician must do it and certify it, grid-connected systems need inspection, and your lines company must approve export before you switch on. See the guide. Mounting panels and DC-side layout planning are things you can do a lot of the thinking on yourself.
Your bill shows kWh per month or year. NZ homes average around 19 kWh a day.
Modelled optimal-tilt yield (PVGIS 2005 to 2023) less 10% for a real roof. Use NIWA SolarView for your address.
100% means the array makes as much over a year as you use. Export limits may cap this.
Sizes the battery to carry the evening and night. 50 to 70% is typical.
Wattages actually on sale in NZ right now.
Cloudy days the battery must carry alone.
Everything that might run at once. A kettle alone is ~2000 W.
Sizing
Parts list, cheapest current offer per line
Prices are the cheapest offer in the index at the last capture, NZD incl. GST unless the supplier says otherwise, excluding freight, labour, consumables and consenting. Lines marked indicative are placeholders for a category where quantity depends on your roof; open the category to choose. Click any line for alternatives.