Plan solar budgets with defensible levelized costs. Model replacements, escalation, and output decline over years. Download reports and share numbers with your team easily.
| Plant (kWdc) | Capex per kW | Life (yrs) | Capacity factor | Losses | Discount rate | Illustrative LCOE |
|---|---|---|---|---|---|---|
| 500 | $ 850 | 25 | 20% | 7.5% | 7% | $ 0.055–0.075 / kWh |
| 1000 | $ 780 | 30 | 22% | 8% | 6.5% | $ 0.045–0.065 / kWh |
The levelized cost of energy (LCOE) is calculated as the ratio of discounted lifecycle costs to discounted energy produced:
For site-based solar, capex is shaped by civil works, foundations, trenching, and interconnection. A per‑kW figure should reflect the full installed scope, including permitting, protection systems, and commissioning. Many projects fall near 650–1,200 per kW depending on scale, mounting type, and grid tie distance. Use contingency to cover geotechnical uncertainty, logistics, and schedule compression. Separating DC and AC ratings improves consistency when comparing vendor proposals and layouts early.
Energy is modeled from either capacity factor or specific yield. Specific yield is best when you have simulation or measured data. Typical capacity factors fall near 15–28% depending on latitude, shading, and tracking. Apply system losses for soiling, wiring, downtime, and clipping; many sites use 6–14% as a planning band. Then apply degradation annually, often 0.3–0.8% per year, to reflect gradual output decline.
Fixed O&M per kW-year captures inspections, vegetation control, cleaning, and spares. Variable O&M per MWh covers production-linked fees, metering costs, and monitoring services. A common fixed O&M range is 10–25 per kW-year, while variable costs often sit near 0–5 per MWh. Escalation adjusts these costs over time; set it to 0 for constant purchasing power.
LCOE is sensitive to the discount rate because it weights early costs more than future energy. Use a rate that matches your financing approach; many pro formas use about 5–10%. If you select a real rate, keep escalations near zero; if nominal, align escalation with expected price growth. Review present value totals to confirm the model fits your valuation method.
Many projects include inverter replacement around years 10–15 and end-of-life removal planning. This calculator includes a replacement year, replacement cost per kW, decommissioning cost, and salvage percentage. Replacement allowances commonly range from 30–90 per kW depending on equipment class and access constraints. Use the discounted cashflow table to see when costs peak and export results for review.
It is the discounted lifetime cost divided by discounted lifetime energy. The result is a comparable cost per kWh that helps evaluate competing designs, sites, and procurement options.
Use specific yield when you have site simulation or measured data in kWh/kW-year. Use capacity factor when you only have a percentage estimate of annual utilization.
Losses reduce Year‑1 gross energy to net energy before degradation. This keeps wiring, soiling, downtime, and clipping impacts visible and prevents overstating lifetime production.
Incentives reduce the upfront cost used in discounted costs. Lower initial cost generally reduces LCOE, especially when the discount rate is high.
Energy arrives over decades, but capex is paid early. A higher discount rate reduces the present value of future energy more than early costs, pushing the LCOE upward.
Choose a replacement year aligned with warranties and operating strategy, commonly 10–15 years. Enter a per‑kW cost that includes equipment, labor, access, and commissioning for that event.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.