A new meter is installed as part of your system. The electricity you produce is metered and you are paid for it, before any power is used by you. If you have an existing service at that site, there are no changes to your existing usage, you are still metered for all electricity used and receive a bill as usual.
The OPA changes the tariff rate every year, starting January 1st.
See the Ontario Feed-In Tariff Rates: Feed-In Tariff
Verify your land classification: Land Inventory Maps