The PV Fleet Performance Data Initiative, created by the U.S. Department of Energy and NREL, collects operating data from PV plants larger than 250 kW into a secure central database: performance at 15-minute intervals, weather, irradiance, and system specifications, over multi-year periods.
Its purpose is to establish how the U.S. fleet actually degrades over time. Module-level degradation had been studied extensively, but as the initiative notes, little was known about degradation rates and performance across the entire U.S. fleet before this database existed. Contributing organizations receive a custom performance analysis using NREL’s RdTools software, and their data stays confidential and anonymised in public reporting.
How it gets used on a real project
Degradation rate is an assumption that compounds across every year of a 25-year model, and it is routinely set by convention rather than evidence. Fleet-derived benchmarks let you check whether the rate in your pro forma resembles what real plants do, and let an asset manager tell the difference between normal ageing and an underperforming site that needs attention.
If you operate qualifying plants, contributing data is also how the benchmark improves, and you get your own fleet analysed in return.