Variation of Round Trip Efficiency with Battery SOC range

  • Arun Joshy
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19 Jun 2019 11:37 #7472 by Arun Joshy
Variation of Round Trip Efficiency with Battery SOC range was created by Arun Joshy
Hi,

While modelling a battery-only case using Detailed PV and 100% losses, I just noticed that the round trip efficiency of the battery is heavily varying with the SOC range of operation, which is not expected. Please find below the output of parametric table for 3 different SOC ranges.
batt_maximum_SOC (%)batt_minimum_SOC (%)average_battery_conversion_efficiency(%)
1100036.811
2901069.633
3802081.219
Could you please explain why these variables are linked? How can this problem be resolved? I am attaching a .SAM file for your reference.

Thanks
Arun Joshy
batt_minimum_SOC (%)
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  • Paul Gilman
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24 Jun 2019 23:37 #7482 by Paul Gilman
Replied by Paul Gilman on topic Variation of Round Trip Efficiency with Battery SOC range
Hi Arun,

On the Battery Storage page, under "Voltage Properties" you should see a voltage discharge vs depth of discharge graph. For Lithium-ion batteries, the voltage drops steeply as depth of discharge increases for depth of discharge values above about 80%. That causes the lower roundtrip efficiencies you are seeing as you allow the battery state of charge to increase above that point.



Best regards,
Paul.
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