Hi Brett,
Yes, for photovoltaic-battery systems, you can use the battery to reduce peak demand charges.
Once you've designed the PV system, assigned costs, and defined financial parameters as you would for a PV-only system, you'll add a battery on the Battery Storage page. For the battery, you choose a dispatch method: You can either have SAM dispatch the battery to minimize peak demand (one of the peak shaving options) or you can use the manual dispatch inputs to determine the timing of battery charges and discharges manually.
On the Electricity Load page, provide data describing the electricity consumption of the home or commercial building you are modeling.
On the Electricity Rates page, provide information about the rate structure used to calculate the home- or building-owner's monthly electricity bill. You can download electricity rate data from the NREL Utility Rate Database (URDB).
Please see SAM's Help system for descriptions of the model's inputs and the links listed under "Photovoltaic-Battery Systems" for links to videos demonstrating how to use the battery model:
sam.nrel.gov/webinars
Please feel free to follow up if you have any other questions.
Best regards,
Paul.