20 solar panels capable of 5.5kW generation are mounted on a rack in the garden, with a grid-connected Fronius Primo Converter and Power Reducer (which prioritises the hot water cylinder with the power generated). We decided to continue using the original HWC, even though it is an energy hog; for most days of the year, its needs are met through solar only.

Inside the house, a 10.5kWh Sonnen battery and power back-up system smooths out our consumption, and helps cope with our frequent grid power failures.

Our healthy energy exports to the grid in summer don’t mean much; electricity supply is privatised in New Zealand — we pay 33c per kilowatt-hour from the grid, but receive 7c for exported energy.