High PV charging (3x Smartsolar 250/70) during negative prices

Q&A and troubleshooting DESS
,
1

Hello community.

Short system summary:
3x MPII 5000
3x Smartsolar 250/70
10x Pylontech US5000
DESS with Tibber
Trade mode
Firmware version V3.53.

I have a hard time understanding the following behavour:

At this moment the energy price is €-0,28/kwh so the battery is charging, all good.
But what I can’t understand is that DESS is not limiting the Smartsolars. It is more profitable to charge from the grid at maximum rate than charge from the PV. At this moment the PV is getting priority (9kW) and the MP’s are supplementing to get to the calculated SOC on time.

In my opinion the the system should charge full power from the grid (12kW) to get the maximum profit from the negative prices and only use the PV get to the calculated SOC on time.

I checked all the settings like 3 times and everything looks to be set OK but.

Am I missing something?

Thanks in advance.

J-W

1 Like
2

+1

3

Agree, I have manually turned off my MPPT so as to maximize profit from the negative grid price.

Quick questions: which version of VenusOS are you running ?
Have you installed any mods like the Hack ?
Are you running DESS in Green mode or Trade mode ?

4

I am running trade mode.
Firmware version v3.53, unmodified.

5

trigger a load when the batteries are full..

as a clue to start with

6

Robert Welling. I will watch the video tomorrow but the batteries were not full, not even 50% at the moment of writing.