GCR

Hi

I would like to use Photovoltaic Systems in SAM where I only have one single module. I want to know what value should I use for GCR?? , since I do not have any neighbouring solar panels.

Thanks

Hi Fereshteh,

You can use the default GCR value of 0.3 for a system with one module.

Best regards,
Paul.

Hi Paul,
Thank you very much for the response'

I did simulation in SAM, putting GCR= 0.3. I am using a 50 watts solar panel, with area of about  0.3 m^2. I suppose the value of the total estimated power should be around 0.3 m^2, however; from the simulation I obtained 0.877 m^2. Could you please tell me what I am doing wrong?

Thanks very much and looking forward to hearing from you.

Fereshteh

Hi Fereshteh,

The "Estimated total module area" for the PVWatts model is a rough estimate of the area required by the array for land area calculations. It does not affect the outputs of the model unless you include a financial model that calculates land purchase or lease costs.

For your model of a single module, you should ignore the estimated total module area.

Best regards,
Paul.

Hi ,
I am using the data in Montreal, QC,Canada, and I would like to include DC power loss due to snow in my results, because we have a lot of snow in our area. I am very surprised, when I was checking the data table, because I find out there are alot of days in summer, where we do not have any snow but in the table shows the loss due to snow. 

Thank in advances for your help.

Fereshteh

Hi Fereshteh,

This is a bug in the snow model for PVWatts that we will fix for the next release:

github.com/NREL/SAM/issues/1137

We are planning this release for the end of this month, November 2022.

Best regards,
Paul.