String Inverter vs Microinverter: Which Should You Choose?
The inverter choice affects system performance, cost, monitoring capability, and future expandability. Here's the direct comparison — and what matters most for residential installs in Europe.
| Property | String Inverter | Microinverter | Hybrid Inverter |
|---|---|---|---|
| Cost | Lowest | 30–40% more | Mid-high |
| Shading impact | One panel affects all | Per-panel optimization | Depends (with DC optimizers) |
| Monitoring | System level | Per-panel level | System + battery |
| Battery ready? | No (needs separate) | No (needs separate) | Yes — built-in |
| Failure impact | System down | Only 1 panel affected | System down |
| Lifespan | 10–15 years | 25 years (per unit) | 10–15 years |
| Best for | Simple unshaded roofs | Complex/shaded roofs | Anyone adding battery |
The shading problem: why it matters
With a string inverter, your panels are wired in series. When one panel is shaded, it acts like a kink in a hose — the whole string underperforms. Microinverters operate each panel independently. If your roof has chimneys, skylights, trees, or multiple orientations, microinverters recover significantly more energy. In northern Europe where low sun angles are common in winter, this matters more than in the south.
The hybrid case: plan ahead if you want a battery
Installing a string inverter today and adding a battery later means either replacing the inverter or adding a separate AC-coupled battery (more expensive, less efficient). A hybrid inverter handles both — it's the right choice if you plan to add storage within 5 years. Given falling battery prices and European energy price volatility, most installers now recommend hybrid from the outset.
Our recommendation
- Simple south-facing roof, budget-first: String inverter (SMA Sunny Boy, Fronius Primo)
- Shading or complex roof: Microinverter (Enphase IQ8+)
- Planning to add battery (recommended for most): Hybrid inverter (SolarEdge, GoodWe, Fronius GEN24)