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Title: Improvements to PVWatts for Fixed and One-Axis Tracking Systems

Conference ·
 [1];  [2];  [2]
  1. Envision Digital Corporation
  2. National Renewable Energy Laboratory (NREL), Golden, CO (United States)

This work presents improvements to the widely used NREL PVWatts photovoltaic system energy model to improve modeling accuracy for typical fixed and one axis system designs. The aim is to calculate losses in the PV system assuming typical modern system design practices, while maintaining simplicity by keeping the required set of input parameters small. These improvements allow users to more credibly and quickly evaluate competing system designs in early stage feasibility. Common submodels for module cover, spectral, snow, tracker, transformer, plant controller, and self-shading losses, in addition to a bifacial gain option, are incorporated into the PVWatts model, and are shown to improve PVWatts' system performance prediction capabilities without major impact to ease of use. We anticipate including these improvements in a future release of NREL's open source PVWatts code, and some of the features may become available in the System Advisor Model (SAM) desktop software as well as the popular PVWatts web application.

Research Organization:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Solar Energy Technologies Office
DOE Contract Number:
AC36-08GO28308
OSTI ID:
1603919
Report Number(s):
NREL/CP-6A20-76289
Resource Relation:
Conference: Presented at the 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC), 16-21 June 2019, Chicago, Illinois
Country of Publication:
United States
Language:
English