How can I change the efficiency?
With Node-RED and dbus-path posted above
I’ve already looked at this and not came to a clear conclusiion - but already talking with @dfaber to clearify things and not make a wrong “assumption” about the actual usage.
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It can be adjusted (since candidate release 3.20~17) via the com.victronenergy.settings / Settings/DynamicEss/SystemEfficiency dbus path. If you want to adjust it to e.g. 85%, you can use the following flow:
Summary
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So system efficiency has to be set to the round trip efficiency otherwise it will create losses instead of profit as I understand correctly?
If you can define all the other parameters just as precisely, efficiency is the weakest link in the calculation. Examples of other parameters: How many cycles does your battery last? 4-5-8 or 10,000 cycles? What is much more important when it comes to costs? Or: How much does it cost to replace the battery? €10 or €500 per kWh capacity? The economic viability always depends on many factors. Efficiency is of course one of them. The easiest way to influence the DESS is via the cycle costs of the battery. Whether I enter 2 cents or 8 cents here plays a much more decisive role than an efficiency of 87% or 93% or even completely different numbers.
Cycle cost is total price of battery / maximum cycles. In my case 2000/8000 = 0,25 per cycle.
The RTE is in my case 76%.
Buying and selling without profit is a no go for me, which was happening with a value of 90% set to com.victronenergy.settings / Settings/DynamicEss/SystemEfficiency
Please stay on topic!
Read the initial question and my answer on 23 November.
It looks like the system efficiency is meant for systems with a DC system (like boats). Because this parameter is only for charger-to-battery and pv-to-battery.