You pay a higher daily supply charge and more per kWh outside this window so it's more like free (conditions apply)

The supply charge is 6% higher for the Solar Sharer plan, while the peak rate is 92% higher. Solar Sharer’s peak rate is almost double the flat rate. The off-peak rate is 17% lower than the flat rate.

https://www.solarquotes.com.au/blog/solar-sharer-plans-compa...