Calculation of peak demand

A follow-up to my question in today's webinar: If we use hourly weather data, so the PV simulation is hourly, but our electric load data is quarter-hourly, does SAM look at every 15-minute interval and calculate:

[electric load for the 15-minute period] - [(energy generated in that hour)/4] = demand for that period

and then find the largest value and use it as the peak demand for the month? If not, how does it calculate peak demand in that case?

Hello,

SAM requires that the time step of the data in the weather file and load data be the same, so you would need 15-minute weather data for your analysis.

If you only have an hourly weather file, you can use the procedure described in the following post to convert it:

sam.nrel.gov/node/72606

Note that 30-minute weather data is available from the NREL NSRDB when you download it from the NSRDB website:

nsrdb.nrel.gov/nsrdb-viewer

Best regards,
Paul.

Got it, thanks for the reply.