I think this depends on the grid management and local rules. In Switzerland the PV systems with FiT have a contract with the government, which buys the whole production (autoconsumkption is not possible in these systems) at the FiT.
Only large installations can however benefit from the FiT. Small systems (less than 30 kW peak) get a fixed subsidiary at the construction, and then self consume the production. The excess is sold (at low price) to the grid management, which also provides electric energy (at normal price) when the PV system does not cover the needs.
In some countries, there are net power meters (up to 5 kW capacity). It deducts the energy provided from the energy used. The disadvantage that it does not care with the schedule and different power prices. In most of the cases PV provides energy during peak time. It is a potential issue that solar power increase daily increase can exceed the increase in the energy demand (e.g. PV provide more than 30% of all the demand or lower if AC is not used in the given area).
In Spain, small domestic photovoltaic plants usually have a system that prevents the excess energy from being discharged into the grid. Therefore, self-consumed energy is not directly part of the electricity bill.
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