Currently, only 600W may be fed into the grid without authorisation; a simple notification to the grid operator is sufficient. In Germany it is now probably 800W and a firmware update has been delivered - it is now adjustable. However, as already mentioned, the 800W of the panels are rarely if ever reached as these are measured under optimum conditions in the laboratory

As @rkroemer appropriately mentioned, the output can only be achieved with optimal orientation and weather, if I had more space I would even set up 4 panels and purchase a storage unit >2kWh which, if available, would store the surplus power and feed it back into my home at night (for the fridge, hot water boiler, etc.).