Hi,
I have a relatively new system (one month) and i have a hard time figuring out the choices of the DESS algorythm. 
My system is pretty standard : Multiplus 2 with a RS450/100 and 15kwh of pylontech batteries. With ESS, i expect the system to use first solar, then the battery and last, when the SOC of the battery is low, the grid.
I notice a lot of erratic behaviors, for example :
- not discharging the batteries at night altough they are far from the minimum SOC (which causes the battery to be full early the next day)
- charging the battery from the grid (why??
)
For example, here is the DESS forecast at the moment :
Why the ESS want a SOC of 70% during the night ? I understand that the price are lower but using the battery for the night consumption is better.
My DESS parameters are :
- green mode
- no sell, no feed in from battery
- dynamic price (Tempo, i live in France)
- battery price : 0€
My ESS parameters are :
- mode : optimized without batterylife
- minimum SOC : 10%
- grid set point : 10W
- no feed-in
- no scheduled charge level
- DESS mode : Auto
- peak shaving : above minimal SOC
Thank you 
If you aren’t feeding in, then DESS makes little to no sense to use.
If DESS figures your battery was roo expensive to cycle vs using grid power, rhen it won’t.
Just use scheduled charge levels in ESS to cycle or change as desired.
I would like to use DESS because my buying prices are variable (Tempo) and can be pretty high in winter (0,65€/kwh between 6AM and 22PM during 22 days ).
My aim is to minimize the use of grid during these periods, even with charging the battery with the grid during the night if the wheather forecast is bad.
Otherwise, in summer, i agree, a standard ESS is perfect for my use case.
However, i would like to understand the DESS forecast and tune it to be reliable this winter.
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Another screenshot of bad (in my opinion) behavior of the ESS :
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Hey, I also do have a strange behavior with the forecast, it doesnt get it right…
I always have a load between 150-1000 W in each hour also in the night. The system calculates 0W for tomorrow early morning, therefore it doesn‘t charge up the system properly and its not utilizing the DESS.
Anybody experiencing something similar?
