It can be worth it if there are no more solar specific subsidies on offer.
The lack of an upfront cost of the panels, and mandatory feed-in tariffs (a minimum that retailers have to pay us for the electricity we produce) used to make installing solar systems a good investment. But with the installation reducing in NSW, now's not the best time - you'll need at least 10 years or more before your investment will pay back.
But note that this doesn't mean it is never worth investing in a solar system! The new energy storage solutions such as Tesla Powerwall make up charge electric cars and provide backup power during blackouts, all while earning returns through net-metering rights periods as well when excess energy.