String Inverter vs Microinverter vs Power Optimiser

String inverters: simple and cost-effective

One inverter serves series strings. Ideal for unshaded north planes. Monitoring is usually system-level unless extra sensors are added. A single inverter failure takes the array offline, but replacement is straightforward when spares exist. Still the value king on clean roofs. Treat metro 6.6kW after-STC bands (often $5,000–$8,000) as planning ranges only — roof access, switchboard upgrades and network fees move real invoices outside averages. Use this comparison to brief installers with a clear preference and a fallback — then price both options with the same CEC-accredited shortlist via MrSolar so hardware choices stay constant. Save PDFs of every plan, approval and datasheet — warranty claims years later depend on that trail.

Microinverters: per-panel conversion

Each module (or pair) has its own inverter. Shade on one panel hurts that panel more than the whole string. Monitoring granularity is excellent. Hardware cost and roof complexity rise; servicing means roof time. Great for dormers, chimneys and multi-facet roofs common in older Australian suburbs. A site assessment with photos, stringing plan and shade notes beats brochure layouts; mismatched orientations need separate MPPTs or module-level electronics. Use this comparison to brief installers with a clear preference and a fallback — then price both options with the same CEC-accredited shortlist via MrSolar so hardware choices stay constant. Photograph your switchboard and roof planes before quoting day to cut variation risk.

Power optimisers with a central inverter

Optimisers condition DC at the module while a central inverter handles AC conversion. They offer shade tolerance and module data with different trade-offs to micros. Ensure the exact optimiser + inverter pair is CEC-listed and familiar to your installer. A site assessment with photos, stringing plan and shade notes beats brochure layouts; mismatched orientations need separate MPPTs or module-level electronics. Use this comparison to brief installers with a clear preference and a fallback — then price both options with the same CEC-accredited shortlist via MrSolar so hardware choices stay constant. Save PDFs of every plan, approval and datasheet — warranty claims years later depend on that trail.

Cost versus bill outcome

Module-level electronics can cost more than a string design for the same kW. Pay for them when shade or complex geometry justifies it — not because a brochure says “smart”. STCs still follow system capacity and zone; they do not fund gadget preference. Keep metro 6.6kW after-STC expectations ($5,000–$8,000) in mind when extras stack. Treat metro 6.6kW after-STC bands (often $5,000–$8,000) as planning ranges only — roof access, switchboard upgrades and network fees move real invoices outside averages. Use this comparison to brief installers with a clear preference and a fallback — then price both options with the same CEC-accredited shortlist via MrSolar so hardware choices stay constant. Photograph your switchboard and roof planes before quoting day to cut variation risk.

Batteries and future hybrids

Some hybrid pathways integrate more cleanly with string/hybrid platforms than with certain micro ecosystems. If storage is likely under the Cheaper Home Batteries Program (~$372/kWh usable), confirm compatibility now. Compare three CEC-accredited designs on MrSolar with shade reports attached. Size usable kWh to your 4pm–9pm consumption, confirm CEC listing, and keep federal (~$372/kWh usable) and any state battery support itemised — never as one mystery “government discount”. Use this comparison to brief installers with a clear preference and a fallback — then price both options with the same CEC-accredited shortlist via MrSolar so hardware choices stay constant. Save PDFs of every plan, approval and datasheet — warranty claims years later depend on that trail.

Shade reports beat marketing diagrams

Commission a shade/insolation assessment before you pay for module-level electronics. If the roof is clean north with no dormers, string usually wins on value. If chimneys and trees carve the array into puzzle pieces, micros or optimisers earn their keep. A site assessment with photos, stringing plan and shade notes beats brochure layouts; mismatched orientations need separate MPPTs or module-level electronics. Use this comparison to brief installers with a clear preference and a fallback — then price both options with the same CEC-accredited shortlist via MrSolar so hardware choices stay constant. Photograph your switchboard and roof planes before quoting day to cut variation risk.

Service access and roof safety

Microinverter faults mean roof time; string faults often mean ground-level swap. Factor labour access on multi-storey terrace houses. Whatever you choose, keep CEC product listings aligned across modules and electronics. A site assessment with photos, stringing plan and shade notes beats brochure layouts; mismatched orientations need separate MPPTs or module-level electronics. Use this comparison to brief installers with a clear preference and a fallback — then price both options with the same CEC-accredited shortlist via MrSolar so hardware choices stay constant. Save PDFs of every plan, approval and datasheet — warranty claims years later depend on that trail.

Match inverter topology to your roof — compare CEC-accredited quotes on MrSolar.

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