Expanding an existing solar PV installation
Sources checked
An existing PV system can be expanded only after checking the inverter, wiring, roof and connection conditions. Spare roof area or an unused connector does not prove that more modules can be added. First identify whether you need more daytime generation, evening energy or outage backup.
Check the existing equipment and approvals
Gather model and firmware details, string diagrams, electrical records, roof assessment and the agreed grid connection. Additional modules must fit voltage, current and MPPT limits. Panel models and orientations can affect the feasible arrangement.
An increase in panel power is different from changing inverter power or permitted export. Confirm what the distributor requires for the actual modification.
Compare the change as a separate project
Ask for the precise design, itemised additional cost and updated settings and documentation. Identify effects on original warranties and responsibility for mixed old and new equipment.
If the main problem is evening use, more panels may not be the best response. Compare demand shifting and a supported battery retrofit using the same consumption and financial assumptions.