We will be performing a major infrastructure and web site ugprades on Friday, September 27th 8:00 am - 5:00 pm MST (UTC -7).

The website will be down during that time.

Performance Ration VS Total System Loss

  • Elkhadh
  • Topic Author
More
08 Jan 2021 15:44 #9164 by Elkhadh
Performance Ration VS Total System Loss was created by Elkhadh
Hello,
I start using SAM for sizing PV system with PVWatts, and in the System Design inputs I've put total system loss as 19%, after running simulation, in the result page I can't find the PR (Performance Ration) value of the system! is it assumed that the PR is the total loss ? i.e 81%=100%-19% ? if yes is it relevant as per IEC definition of the PR ?

Regards,

Please Log in or Create an account to join the conversation.

  • pgilman
More
11 Jan 2021 21:26 #9180 by pgilman
Replied by pgilman on topic Performance Ration VS Total System Loss
Hi,

PVWatts does not report the performance ratio, but you should be able to use the other outputs of the model to calculate it yourself.

The "total system losses" input accounts for losses that are not calculated by the model. PVWatts calculates losses such as those caused as light passes through the module cover and the conversion of light to DC power. For details see the PVWatts reference manual, available from this page under "PVWatts:" sam.nrel.gov/photovoltaic/pv-sub-page-2.html.

Best regards,
Paul.

Please Log in or Create an account to join the conversation.

Moderators: pgilman
Powered by Kunena Forum

NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.

NREL Home

NREL Research

Follow NREL

NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.