Ecology & Environment
Solar Production Schedule Calculator
Project annual and lifetime solar production, final-year output, avoided electricity value, maintenance cost, net value, and a lifetime generation comparison across the selected horizon.
Year-1 production (kWh/year)-
Production in final modeled year (kWh/year)-
Cumulative modeled production (kWh)-
Year-1 avoided electricity value-
Annual avoided-value growth after degradation-
Cumulative gross avoided value-
Entered maintenance through horizon-
Avoided value minus entered maintenance-
Lifetime production minus comparison (kWh)-
Decision view
Annual and cumulative solar production
Annual and cumulative solar productionAnnual degrading output and cumulative delivered energy share the exact entered planning horizon.
Exact scenario comparisonAnnual production degradation (%) changes while all other entered assumptions remain constant.
| Annual production degradation (%) | Year-1 production (kWh/year) | Production in final modeled year (kWh/year) | Cumulative modeled production (kWh) | Year-1 avoided electricity value | Annual avoided-value growth after degradation | Cumulative gross avoided value | Entered maintenance through horizon | Avoided value minus entered maintenance | Lifetime production minus comparison (kWh) |
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Period-by-period detail
Annual solar production and value schedule
How to use Solar Production Schedule Calculator
- Enter DC system size and year-one specific yield.
- Enter annual degradation, horizon, and electricity-value escalation.
- Enter annual maintenance and a lifetime generation comparison.
- Review both annual production area and cumulative generation curve.
Calculator guide
Understanding Solar Production Schedule Calculator
Solar production typically declines slowly while the value of each kilowatt-hour can escalate. This calculator keeps physical generation, electricity value, maintenance, and the comparison target on separate schedules.
Calculation method
How the calculation works
Project year-one generation from installed size and specific yield, degrade production annually, escalate electricity value separately, and tabulate annual and cumulative quantities. Multiply system size by year-one specific yield, apply compound annual degradation to production, apply price escalation separately, and sum both geometric schedules.
Detailed calculation process
Project degrading production and escalating avoided value
The defaults model an 8.5 kW system yielding 1,350 kWh/kW in year one, with 0.5% annual degradation over 25 years.
General formula: E_1 = PK; E_y = E_1(1-d)^(y-1); E_L = E_1[1-(1-d)^n]/d; v_y = v_1[(1-d)(1+g)]^(y-1); V_L = sum(v_y)-nM Installed power times specific yield gives year-one energy. Each later year retains one minus the degradation rate. Energy value compounds both the production retention factor and the electricity-price escalation factor.
What each symbol means
Worked substitution with the default inputs
The default system produces about 270,304.5 kWh over 25 years and $57,517.1 of modeled net avoided value after entered maintenance.
Production outlook
Separate annual decline from cumulative delivery
The area chart shows annual kWh while a cumulative curve answers the lifetime question.
Worked situations
Practical examples
- Year-one production is 11,475 kWh.
- Year-25 production is about 10,174.349 kWh.
- Lifetime production exceeds the entered comparison by 10,304.542 kWh.
Better inputs
Useful tips
- Use a site-specific modeled or measured year-one yield.
- Keep degradation and tariff escalation as separate assumptions.
- Test inverter replacement and variable maintenance outside this fixed annual allowance.
Before relying on the result
Limitations and common mistakes
- Weather, shading, clipping, curtailment, soiling, outages, and component replacement are not simulated.
- Export compensation and retail offset can value identical energy differently.
- The monetary result excludes financing, taxes, incentives, discounting, and residual value.
Reference
Key terms
- Specific yield
- Annual energy per installed kW.
- Degradation
- Modeled annual fractional reduction in output.
- Avoided value
- Electricity purchase value displaced by modeled generation.
Important note
Calculated from the entered environmental values using the displayed model. Measurement quality, local conditions, system boundaries, and source data affect interpretation.
Frequently asked questions
Why is the year-25 exponent 24?
Year one is the starting value, so only the 24 transitions after it apply degradation.
Why is net value still growing when production declines?
The default 2% price escalation is larger than the 0.5% degradation effect.
Is specific yield panel efficiency?
No. It is annual AC energy per installed DC kW under stated conditions.
Is this discounted cash flow?
No. The total is undiscounted and uses a fixed annual maintenance input.