ROI of Photovoltaics – When Will Your System Pay for Itself 2026
19/04/2026
"In how many years will it pay for itself?" – this is the question everyone asks before buying. Here you will find the answer with numbers and real-life examples.
Payback Period by System Size
| System | Cost | Annual Savings | Payback Period | 20-year Profit |
|---|---|---|---|---|
| 3kW on-grid | €4,500 | €900 | 5 years | ~€13,500 |
| 5kW on-grid | €7,000 | €1,400 | 5 years | ~€21,000 |
| 5kW + 10kWh battery | €14,000 | €1,700 | 8 years | ~€20,000 |
| 10kW on-grid | €12,000 | €2,500 | 5 years | ~€38,000 |
Real-Life Example
George in Athens used to pay €2,400/year to the Public Power Corporation. He installed a 5kW system with Longi panels and a Victron MPPT. Cost: €7,000. Annual savings: €1,400. Payback period: 5 years. Profit in 20 years: ~€21,000.
💡 Tip: Every 1% increase in electricity prices improves your ROI by 3-4 months. Electricity prices have increased by 40%+ in the last 5 years.
What affects ROI?
- ⬆️ Electricity price — the more expensive, the faster the payback
- ☀️ Regional sunshine — Crete vs. Northern Greece
- 💰 Subsidy — reduces initial cost by up to 40%
- 🔌 Self-consumption — the more electricity you use from the system
FAQ
How do I maximize my ROI?
Consume electricity mainly during the day (washing machine, air conditioner), minimize consumption at night, and check for subsidies.
Does shade affect ROI?
Yes, significantly. For shaded roofs, we recommend micro inverters or optimizers.
Is ROI calculated with or without subsidies?
Both! We usually calculate without subsidies to be conservative. With a 40% subsidy, the payback period becomes almost twice as fast.