Outdoor PV degradation comparison

Abstract

As photovoltaic (PV) penetration of the power grid increases, it becomes vital to know how decreased power output may affect cost over time. In order to predict power delivery, the decline or degradation rates must be determined accurately. At the Performance and Energy Rating Testbed (PERT) at the Outdoor Test Facility (OTF) at the National Renewable Energy Laboratory (NREL) more than 40 modules from more than 10 different manufacturers were compared for their long-term outdoor stability. Because it can accommodate a large variety of modules in a limited footprint the PERT system is ideally suited to compare modules side-by-side under the same conditions.

Long-term performance analysis of copper indium gallium selenide thin-film photovoltaic modules

“…5 Degradation rates similar to those observed in Florida were also reported recently during a three-year study at Hokuto testing site of the Japanese Mega-Solar project. CIGS thinfilm modules are known for their metastable behavior.…”

Multi‐pronged analysis of degradation rates of photovoltaic modules and arrays deployed in Florida

“…The larger uncertainty values for CEL, as compared with MMS, are due to the shorter monitoring period. This has been shown to be the case in past studies as well , and it makes sense intuitively, because less monitoring time would likely mean less certainty in establishing a clear degradation trend.…”

An unsupervised method for identifying local PV shading based on AC power and regional irradiance data

“…This ensures, that the fitted parameters ( sh diff _ and cl ) in the grey-box model represent the current state of the installation, as cl accounts for slowly changing characteristics of the system as well, such as soiling and degradation. In a one year timeframe, we assume, that with adequate maintenance and typical degradation rates, such as 0.5%/year (Jordan et al, 2010) cl can be modeled as a time-invariant. Moreover, changes in the urban landscape, such as new buildings or cut trees can be accounted for with the yearly repetition of the training process.…”