Feed in tariffs (FIT)
For larger solar systems, your electricity retailer might not offer much of a feed-in tariff to purchase excess electricity from you, or they may offer none at all and limit your export opportunity depending on the size.
It is important to understand this and consider it in the financial modelling to size a solar system to achieve a minimum amount of solar export.
However, a financially optimised solar system could be sized to export electricity at certain times even with a zero feed-in tariff. It may for example export energy in summer to have sufficient solar energy for self-use in winter.
An ISC or solar engineer will be able to help you navigate this challenge.