Solar calculator
Everything starts in the simulator: type your consumption or take it from your bill or the map, and watch the financial model live.
1How much electricity do you use?
Or take it, more precisely, from:
2How big should the plant be?
Recommended from your consumption
That size means 8 panels and about 29 m² of roof.
3How will you pay?
Annual interest 14% — per the referenced financing scheme.
A 4.8 kW plant would earn you about 46 million toman in its first year and pay for itself in about 9.9 years.
Project cost
497 million toman
Down payment: 159 million toman
Monthly instalment
7.9 million toman
Repaid over 60 months
Payback period
9.9 years
From the cumulative cash flow
System size
4.8 kWp
8 panels · ~29 m²
Year-one production
7,900 kWh per year
Year-one income: 46 million toman
25-year net profit
2.9 billion toman
After costs, inverter replacement and instalments
Return on investment
1,805%
IRR: 16%
These figures are a simulation. For the formal assessment sheet — with price ranges and a plant proposal — complete the assessment.
25-year cash flow
Bars: yearly net · line: cumulative · dashed: payback
Monthly production (year one)
Three scenarios
Selected scenario: project cost 497 million toman · year-one income 46 million toman
Cash versus financing
| Cash | Financing | |
|---|---|---|
| Initial investment | 497 million toman | 159 million toman |
| Monthly instalment | — | 7.9 million toman |
| Total interest | — | 134 million toman |
| Payback | 8.4 years | 9.9 years |
| 25-year net profit | 3 billion toman | 2.9 billion toman |
| Return on investment | 605% | 1,805% |
Year-by-year financial modelopen for the full table
| Year | Production | Revenue | Costs | Loan | Net | Cumulative |
|---|---|---|---|---|---|---|
| 1 | 7,900 | 46 million toman | 5 million toman | 94 million toman | −53 million toman | −212 million toman |
| 2 | 7,900 | 51 million toman | 5.5 million toman | 94 million toman | −49 million toman | −261 million toman |
| 3 | 7,800 | 55 million toman | 6 million toman | 94 million toman | −45 million toman | −306 million toman |
| 4 | 7,800 | 61 million toman | 6.6 million toman | 94 million toman | −40 million toman | −346 million toman |
| 5 | 7,700 | 66 million toman | 7.3 million toman | 94 million toman | −35 million toman | −382 million toman |
| 6 | 7,700 | 72 million toman | 8 million toman | — | 64 million toman | −317 million toman |
| 7 | 7,600 | 79 million toman | 8.8 million toman | — | 70 million toman | −247 million toman |
| 8 | 7,600 | 87 million toman | 9.7 million toman | — | 77 million toman | −170 million toman |
| 9 | 7,500 | 95 million toman | 11 million toman | — | 84 million toman | −86 million toman |
| 10 | 7,500 | 104 million toman | 12 million toman | — | 92 million toman | 6.1 million toman |
| 11 | 7,500 | 113 million toman | 13 million toman | — | 100 million toman | 106 million toman |
| 12 | 7,400 | 124 million toman | 156 million toman | — | −32 million toman | 74 million toman |
| 13 | 7,400 | 135 million toman | 16 million toman | — | 120 million toman | 194 million toman |
| 14 | 7,300 | 148 million toman | 17 million toman | — | 131 million toman | 325 million toman |
| 15 | 7,300 | 162 million toman | 19 million toman | — | 143 million toman | 468 million toman |
| 16 | 7,200 | 177 million toman | 21 million toman | — | 156 million toman | 624 million toman |
| 17 | 7,200 | 193 million toman | 23 million toman | — | 171 million toman | 795 million toman |
| 18 | 7,100 | 212 million toman | 25 million toman | — | 186 million toman | 981 million toman |
| 19 | 7,100 | 231 million toman | 28 million toman | — | 204 million toman | 1.2 billion toman |
| 20 | 7,100 | 253 million toman | 30 million toman | — | 223 million toman | 1.4 billion toman |
| 21 | 7,000 | 277 million toman | 33 million toman | — | 243 million toman | 1.7 billion toman |
| 22 | 7,000 | 302 million toman | 37 million toman | — | 266 million toman | 1.9 billion toman |
| 23 | 6,900 | 331 million toman | 40 million toman | — | 290 million toman | 2.2 billion toman |
| 24 | 6,900 | 361 million toman | 44 million toman | — | 317 million toman | 2.5 billion toman |
| 25 | 6,900 | 395 million toman | 49 million toman | — | 346 million toman | 2.9 billion toman |
Calculation assumptions
- Specific yield (net of losses)
- 1,650 kWh/kWp·yr
- Guaranteed purchase per kWh
- 5,854 toman
- Annual purchase-price growth
- 10%
- Annual panel degradation
- 0.6%
- Annual O&M (of project cost)
- 1%
- Inverter replacement
- Year 12 — 10% of project cost
- Financing
- 14% annual interest
- Discount rate (NPV)
- 15%
- Net present value (NPV)
- 19 million toman
- Project lifetime
- 25 years
- Assumptions version
- invest-market-anchor-1405.05
These results are approximate estimates from the stated assumptions, not a promise of return. Final system size, equipment prices and connection terms are confirmed after technical assessment and a site visit.
Project cost497 million toman
Monthly instalment7.9 million toman
Payback period9.9 years