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Off-Grid System

  • Macosta
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27 Mar 2020 13:44 #8075 by Macosta
Off-Grid System was created by Macosta
Suppose I want to run a system without any power interchange with the grid- The system is a PV+Battery. Is it possible to do it? I did something that want to expalin:
1.- I designed my system with more capacity than load requirements (in kW and kWh).
2.-On the battery sheet, I declared an Input Grid Power Target with an 8760 time series with "0" interchange.
3. On the Grid Interconnection limits, I put 0 kW.

The system run but when there is more DC power available than required by load and batteries are full, the system is overriding the grid limit and export kW into the grid. Is it possible to improve the simulation for indicating that in such cases the inverter must work outside the Maximum Power Tracking Point and reduce the power conversion for complying with the restriction?

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  • pgilman
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27 Mar 2020 20:29 #8078 by pgilman
Replied by pgilman on topic Off-Grid System
Dear Manuel,

SAM is not designed to model off-grid systems. We have not tried the workaround you suggest.

Rather than using the interconnection limit to try to force the system not to export to the grid, a better approach might be to design the PV array, inverter, and battery bank so that the system can meet the load without the grid. SAM might still use some small amount of grid power, but if you set the retail electricity rates to zero so that the cost (and value) of that power is not included in your financial analysis, that approach might get close to modeling an off-grid system.

I would be happy to take a look at your approach if you could attach your .sam file for me to review.

Best regards,
Paul.

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  • LuizPereira
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28 Sep 2020 13:22 #8790 by LuizPereira
Replied by LuizPereira on topic Off-Grid System
Hi Manuel,

Have you get to solve this problem? I'm trying to simulate the same thing than you (off-grid system). Do you have any tip related to this?

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