If you've worked in solar project finance, you've likely encountered the term "8760 model." But what exactly does it mean, and why should you care?
What is 8760?
8760 refers to the number of hours in a year (365 days × 24 hours). An 8760 energy simulation model creates an hourly profile of expected solar generation for every hour of the year.
Why Hourly Simulation Matters
Daily or monthly averages simply don't cut it for project finance. Here's why:
- Solar variability — Generation peaks at noon, drops to zero at night
- Grid constraints — Hourly profiles reveal clipping and curtailment risks
- Revenue forecasting — Time-of-day pricing affects project economics
- Degradation modeling — Performance changes hour-by-hour over project lifetime
Key Inputs
- Solar irradiance data (GHI, DNI, DHI)
- Temperature data
- System specifications (module type, tilt, azimuth)
- Loss factors (soiling, shading, inverter efficiency)
My Approach
I use Python with Pandas for data processing, validated against PVsyst outputs. The combination gives flexibility for custom analysis while maintaining credibility with industry-standard tools.
Key Takeaway
Never rely on simple capacity factor estimates for serious project finance work. An 8760 model is the minimum standard for investment-grade analysis.