What happens during long periods of cloudy winter weather?

100UP designs for worst-case winter — not as a margin guess, but as the baseline that sets array size, battery autonomy, and backup strategy.

During extended cloud in regional Victoria winters, three layers work together:

1. Oversized solar array — sized to harvest maximum power in brief 1.5–2 hour winter sun windows
2. Battery autonomy buffer — typically ~48 hours stored energy so consecutive low-production days don’t force generator use
3. Generator as backup — auto-starts only if solar and battery reserves are depleted; rare on a well-designed system

On a correctly sized regional VIC install, generator runtime stays minimal — often zero in normal winters, higher only on demanding sites or heavy occupancy.