Inverters

Hybrid vs string inverter: which do I need in South Africa?

Q: Hybrid vs string inverter: which do I need in South Africa?

In South Africa, most homes chasing bill savings plus optional backup choose a hybrid inverter (solar + battery + self-consumption). A pure string / grid-tied inverter is cheaper day-one and excellent when your goal is daytime tariff offset with a stable grid — but it disconnects when the municipal or Eskom supply fails, so panels alone will not keep essentials on. Pick topology from your savings goal first; treat outages as secondary design input.

In South Africa, most homes chasing bill savings plus optional backup choose a hybrid inverter (solar + battery + self-consumption). A pure string / grid-tied inverter is cheaper day-one and excellent when your goal is daytime tariff offset with a stable grid — but it disconnects when the municipal or Eskom supply fails, so panels alone will not keep essentials on. Pick topology from your savings goal first; treat outages as secondary design input.

Plain definitions

String / grid-tied

Converts PV to AC and syncs to the grid. No battery port (or limited). Shuts down on grid failure (anti-islanding). Best when your goal is daytime bill cut and the grid is mostly stable.

Hybrid

Manages PV, battery and grid; can create a backup island for essentials. The default SA residential design for Stage 4–6 living.

Off-grid / multi-mode

Designed to run without a reliable grid — larger storage, generator integration. Overkill (and costlier) for most suburban homes that still have a municipal connection.

What wholesaler training desks emphasise

Trade catalogues (Rexel UK solar books, Sonepar PV/EV curricula) push the same decision tree: pick topology from the use case, then match battery protocol and AC protection. SA adds one non-negotiable filter — NRS 097 type-tested inverters on your metro’s approved list where one exists.

When string still makes sense

Commercial daytime-only sites with strong grid and no backup requirement.
You already own a separate battery inverter / AC-coupled plan (rare for new builds).
Budget forces a staged approach: PV first, hybrid retrofit later — plan cable routes and DB space now.

When hybrid is the safer consumer choice

Any serious load-shedding backup design.
You want one box that installers and municipalities understand.
Future EV charging or heat pumps that need scheduled battery / PV soak.

Typical SA residential hybrids discussed in quotes sit in the ~5–8 kW single-phase class; large homes and three-phase supplies step up. See inverter sizing.