Skip to main content

Plant Parameters

Solar Power Plant
Select the installation country
Typical residential installation: 3-6kWp (10-20 panels of 400 W each).
Hand-in-hand 2026: €1,200 -€1,800 /kWp (panels+inverter+installation)
Energy Consumption and Prices
Battery life (without battery): 25-35%. Battery life (with battery): 60-80%.
Eurostat by default Italia: 0.28 €/kWh
Entry tariff 20260.085 €/kWh
Tax incentive 2026 36%
Net cost after incentives5,760 €

ROI Results

Annual production (year 1)
5,934
kWh
Annual savings (year 1)
852
€/anno
Simple revenge
6.8
years
Return on Investment (ROI) of 25 years
248.2%
Total return
Present Value of $1 in 25 years at a discount rate of 4%
6,901
Total savings of 25 years
20,059
Only network for 25 years −21,300 €
vs
With photovoltaic for 25 years+20,059 € risparmiati

Payback Chart - Cumulative Cash Flow

Cumulative cash flow (£)Payback period : 6.8 anni
Show year-by-year data table
YearProduction kW/h (or Production kilowatt-hours)Save moneyCumulative response: €Cumulative cash flow (€)
15,934852852 -4,908
25,9048471,699 -4,061
35,8758432,542 -3,218
45,8458393,381 -2,379
55,8168354,215 -1,545
65,7878305,046 -714
75,7588265,872 112
85,7298226,694 934
95,7018187,512 1,752
105,6728148,326 2,566
115,6448109,136 3,376
125,6168069,942 4,182
135,58880210,744 4,984
145,56079811,542 5,782
155,53279412,335 6,575
165,50479013,125 7,365
175,47778613,911 8,151
185,44978214,693 8,933
195,42277815,471 9,711
205,39577416,245 10,485
215,36877017,016 11,256
225,34176617,782 12,022
235,31476318,545 12,785
245,28875919,304 13,544
255,26175520,059 14,299

Come utilizzare

Seleziona il paese e la dimensione impianto

Scegli il paese EU dove installi i pannelli e inserisci la potenza in kWp. Un impianto residenziale tipico è 3-6 kWp (10-20 pannelli da 400W). Il tool usa la produzione media nazionale (kWh/kWp).

Inserisci il costo e il prezzo elettricità

Il costo tipico 2026 è €1.200-1.800/kWp chiavi in mano (pannelli + inverter + installazione). Il prezzo elettricità è pre-compilato con la media Eurostat per il paese; puoi personalizzarlo con il tuo contratto.

Stima la quota di autoconsumo

L'autoconsumo è la % di energia solare usata direttamente (non immessa in rete). Senza batteria: 25-35%. Con batteria: 60-80%. L'energia eccedente viene immessa in rete alla tariffa incentivante del paese.

Analizza ROI, payback e NPV

Il grafico mostra il cash-flow cumulato: sotto lo zero significa investimento non ancora recuperato. La linea verticale indica il payback. ROI 25 anni e NPV a 4% misurano la convenienza finanziaria complessiva.

Domande frequenti

How is annual production calculated?

Production = kWp × kWh/kWp/year × (1 - 14% system losses). System losses include inverter efficiency, cables, reflection, and temperature. Each year production decreases by 0.5% (standard panel degradation IEC 61215). The kWh/kWp/year value is the mean PVGIS JRC for the country.

What does the network entry fee cover?

Feed-in tariff is the payment received for every kWh sold to the grid. For IT: GSE Withdrawal Dedicated ~0.085 €/kWh. For DE: EEG 2026 ~0.082 €/kWh. For UK: Smart Export Guarantee ~0.18 €/kWh. These tariffs are subject to annual review.

How do incentives work for countries?

No direct tax incentives 2026.

Why is the ROI different between countries with more sunlight?

ROI depends on three factors: solar production (sun), electricity price (savings per kWh self-consumed), and incentive tariff (compensation for injection). Spain has more sun but lower electricity prices; the UK has less sun but the highest SEG EU tariff (0.18 €/kWh). The NPV normalizes these differences.

Does the calculation take into account battery storage?

No. The tool does not model battery storage systems. Without a battery, typical self-consumption is 25-35%. With a battery, it increases to 60-80%, significantly improving ROI. Manually insert a higher % autoconsumption if you plan to install a battery.

What's not modeled (edge case)?

Not considered due to: (1) suboptimal orientation (East/West reduction -10-20%); (2) shading from trees/buildings (-5-15%); (3) future electricity price growth (+2-4%/year increase in real ROI); (4) O&M costs (maintenance ~€100-150/year); (5) inverter replacement year 12-15 (~€800-1.500).