Battery modeling question

Hi, I simulated two systems with batteries, like this:
1 - 1000 kWh battery and desired bank power 1000 kW = total system energy 6,155...
2 - 1000 kWh battery and desired bank power 3000 kW = total system energy 6,149...
My battery completely drains every day when energy is most expensive. However, when I put a higher power, that energy drops. Therefore, I have a power that provides the most energy. Does this happen due to the efficiency of the DC-DC converter (DC coupling) in SAM modeling?
What documentation or article can I access updated modeling?

Hi Pão,

How SAM discharges and charges the battery depends on several factors, including whether the battery is front of the meter or behind the meter, the battery capacity and dispatch options you choose among other things. If you attach a .sam file that demonstrates those results or describe more of the options you are using, I will be better able to answer your question.

There are some videos of the updates to the battery model in SAM 2021.12.02 here: sam.nrel.gov/battery-storage/battery-videos.html

And the Help system should reflect the latest changes, although we are making more revisions for the first update to SAM 2021.12.02.

For detailed descriptions of parts of the battery model, see: sam.nrel.gov/battery-storage/battery-publications.html

Best regards,
Paul.

I really enjoyed the video. 

So, in my case I only changed the power of charge and discharge, I use "look ahead" in an application to inject energy into the grid. Hence, changing only the power, I realized that when it reaches a limit, the greater the power of charge and discharge, the less energy is injected. I believe it is about efficiency, I will study the model as well.

I studied your paper and it helped to clarify doubts. I have a variation of scenario in this case in my simulations that I charge the battery with the grid. Here before, I only worked charging with photovoltaic. When I charge with the grid, does this value end up being subtracted from the "annual energy" in results? Or is the "annual energy" just the energy injected into the grid by battery and photovoltaic? Well, in the "system power generated" chart, you can see that the value is subtracted (negative power that comes from the electrical grid to the battery).

Or is the value "annual energy" different from the integral of the "system power generated" chart?

Hi Pão,

Annual energy is electricity injected into the grid by the system, so it might be from the PV array or discharged by the battery.

For SAM 2021.12.02 r1 (the first update to SAM 2021.12.02), we are making some changes to the labels of those annual energy variables and adding some new ones to hopefully make it clearer what they mean. We hope to get that update out by the end of this week (week of Feb 14, 2022).

Best regards,
Paul.