Micro Inverter vs String Inverter – Which to Choose for Photovoltaics in 2026
19/04/2026
Do you have shade on your roof? Or panels facing different directions? This inverter choice can make a 15-25% difference in your performance.
What is a String Inverter?
A string inverter is a central unit that converts all panel output to AC. It is the most widespread solution in Greece. Problem: if one panel is shaded, the entire system is affected.
What is a Micro Inverter?
A micro inverter is installed on each panel separately. Each panel operates independently — if one is shaded, the others continue normally.
Comparison by Feature
| Feature | String Inverter | Micro Inverter |
|---|---|---|
| Cost | ✅ Low | ⚠️ +30–50% more expensive |
| Performance in shade | ❌ Low | ✅ Excellent |
| Monitoring | Overall | ✅ Per panel |
| Warranty | 5–10 years | ✅ 25 years |
| Installation | Simple | More complex |
| Ideal for | Large installations | Shaded roofs |
Real-life example
Nikos in Athens had a chimney and a tree that shaded 3 panels. With a string inverter, his output dropped by 28%. With a micro inverter, the output remained stable. Savings: €380/year more.
💡 Tip: If your roof has shade or panels in different directions, a micro inverter usually pays for itself in 3-4 years from savings alone.
When to choose what?
- String Inverter with MPPT: Clear south-facing roof, large installation, limited budget
- Micro Inverter: Shaded roof, multiple directions, want per-panel monitoring
- Victron MultiPlus-II: For hybrid and off-grid with batteries
FAQ
Can I upgrade from a string to a micro inverter later?
Yes, but it requires replacement and additional cost. It is usually more cost-effective to do it along with panel replacement.
Is the micro inverter reliable?
Yes — the 25-year warranty says it all. Manufacturers guarantee their performance and longevity.
Which is better for Greece?
The string inverter dominates due to cost. However, if you have shading, the micro inverter performs much better.