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sonnen-tools / node-red

Node Red Flows for use with Sonnenbatterie
GNU General Public License v3.0
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Not charging up to expected SOC #21

Open doncuco opened 10 months ago

doncuco commented 10 months ago

Hello, I had the issue, that the battery is not charging to my expected soc a few days now.

I See that the log tells that there have been 21114W "charged". But I think this is my house consumption in that time. And because we have a heat pump and it is very cold these days we hat a few kW consumption a this resulted in only 53% charging state. so the other 47% were used by the house in that time. is this possible? And in my charging window there should have been more hours to charge. So do you use the calculated watts for charging and detecting? Or do you use the soc?

Best regards, Tobias

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markusjnagel commented 10 months ago

Hi Tobias @doncuco - you could be hitting this issue https://github.com/sonnen-tools/node-red/issues/6 which I have fixed partly in 0.0.3-WIP but fully in 0.0.4-WIP (which I haven't released yet, sorry... will do on or after next Thursday).

If you check the issue I linked above, you could maybe verify if you hit an error (I documented what I did to isolate the error there). Or, just wait until 0.0.4 is released and retry then.

Regarding the "charged" - yeah, I know that this value is unrealistic, I also see higher values than what my battery capacity is... I take this value from the Sonnenbatterie's RemainingCapacity_Wh - but for our purposes, it doesn't matter if it is WattHours or apples, oranges.... as long as it is consistent.

I save the value when I start charging and calculate the difference between the saved value and the actual value when I stop charging. So, I get what has been charged. I use that value in the chargeLog, so I calculate the cost by amount charged. 1000 Wh = 1kWh at 0.30EUR/kWh = 0.30EUR. 2000 Wh = 2kWh at 0.20EUR/kWh = 0.40EUR. Cost per kWh in the battery: Total Cost / Total Charge = 0.70EUR / 3kWh = 0.2333EUR/kWh.

As long as whatever the SB counts is consistent, it doesn't matter - since the relative measure counts. If you multiply both "charges" from the above example with e.g. 2.34567 - you still get the same cost per kWh:

2345.67 Wh = 2.34567 kWh at 0.30EUR/kWh = 0.703701EUR 4691.34 Wh = 4.69134 kWh at 0.20EUR/kWh = 0.938268 EUR

Total Cost / Total Charge = 1.641969 EUR / 7.03701 kWh = 0.2333 EUR/kWh