Title: ESS ‘Optimize for Battery Life’ Mode: Self Consumption Not Auto-Enabling
Post Content:
I am running my Victron ESS system in “Optimize for Battery Life” mode to minimize battery discharge. However, I have encountered a recurring issue:
Issue Description:
1. After 6 PM, when solar production stops, the battery gradually discharges until it reaches the Set SOC (95%).
2. As soon as the battery reaches 95% SOC, two triggers activate:
• SOC is Low
• Battery Life Active
3. After these triggers, battery discharge stops, and Self Consumption is Disabled.
The Main Problem:
• The next morning, when solar production starts and the battery fully charges to 100%, Self Consumption does not re-enable automatically.
• Instead of supplying power from the battery, the system continues to draw power from the grid.
• The “SOC is Low” and “Battery Life Active” triggers do not clear automatically, preventing battery discharge.
• If I manually change the SOC (e.g., from 95% to 96% or 94%) or restart the system, Self Consumption resumes.
Observations:
• When Grid Set Point = -20W, the system suddenly started drawing 1000-2000W from the battery, which was unexpected.
• When Grid Set Point = 1000W, battery drain stopped.
• When Grid Set Point ≈ 3500W, Dynamic ESS mode did not activate after a system restart.
My Questions:
1. Is there a setting to automatically re-enable Self Consumption in Battery Life mode once the battery is fully charged?
2. Is this a bug where the “SOC Low” and “Battery Life Active” triggers do not clear automatically?
3. Should the Grid Set Point be adjusted to a specific value when using “Optimize for Battery Life” to ensure an optimal balance between grid and battery usage?
I have attached a screenshot that shows the issue: The battery is at 98%, yet Self Consumption is still disabled.
Any suggestions or solutions would be greatly appreciated.
Why do you have a min SOC so high? All optimised with battery life does is makes sure your battery has some charge. If you have low charge for a few days in a row it will automatically increase the min SOC to try and achieve 100% SOC and target around 80-90%.
“I cannot set the SOC too low because the grid is always available. However, despite this, the battery still discharges down to the set SOC without any actual usage.”
“After 6 PM, when solar goes off, the battery starts draining at a very minimal discharge rate of 0.7A to 1A. Overnight, it discharges by approx7%to 10%. To prevent this unnecessary daily usage, I had set the SOC to 95%.”
The inverter mode of MultiPlus Il remains on online so it probably keeps drawing some current.
I dont understand how you are using it. ESS for self-consumption is mainly used for overnight usage. You charge the battery during the day and use it at night.
If you have LifePO4 bateries and the grid to maintain the battery SOC, consider no battery life. There will always be a slight margin either side. As example, one of the systems I manage discharge to 70% and the goes into passthru until sunrise when it will first charge the battery up to 73% before switching to consumption. Did it not have some margin, it will switch in-and-out all the time depending on various conditions/loads. My advice is to use the grid setpoint to e.g. only maintain a min grid draw if feeding in risks tripping up a prepaid meter or you risk being charged for exports and the AC/DC feedin settings to manage feeding in excess to the grid as required.
**“In my case, the grid is always available, and I want to minimize unnecessary battery discharge. After 6 PM, when solar is no longer available, the battery starts discharging at a very low rate (around 0.721A). This continues throughout the night, resulting in approximately a 10% SOC drop by morning.
To avoid this unnecessary daily discharge, I have set the minimum SOC to 95%. However, even with grid availability, the battery still discharges until it reaches the set SOC. I am not exporting to the grid; my goal is to optimize the system for battery life and reduce unnecessary cycling.”**
**“I understand that some margin is necessary to prevent frequent switching, but in my case, the battery still discharges at a very low rate (~0.7to1A) overnight, even when the grid is available. This results in an unnecessary SOC drop of about 10% by morning.
I am not exporting to the grid, and I want to minimize unnecessary battery cycling. I have already set a high SOC limit (95%) to prevent deep discharge, but the system still drains the battery until it reaches the set SOC.
Are there any specific settings within ESS or the AC/DC feed-in parameters that can help completely stop this slow discharge when grid power is available?”**
**“I understand that some margin is necessary to prevent frequent switching, but in my case, the battery still discharges at a very low rate (~0.7to1A) overnight, even when the grid is available. This results in an unnecessary SOC drop of about 10% by morning.
I am not exporting to the grid, and I want to minimize unnecessary battery cycling. I have already set a high SOC limit (95%) to prevent deep discharge, but the system still drains the battery until it reaches the set SOC.
Are there any specific settings within ESS or the AC/DC feed-in parameters that can help completely stop this slow discharge when grid power is available?”**
The system will draw power from the battery and all I can then suggest is to look at SEARCH or AES, which is documented in the manual and may further reduce idle power consumption under certain circumstances. Have you tried keep batteris charged mode, as I don’t otherwise understand your use case. You either use the batteries or you don’t and usually cycles are only counted if the battery is discharged beyond a certain point (definitely much lower than 95%) but varies by manufacturer.
Yes, I am aware of the “Keep Batteries Charged” mode, but my goal is slightly different.
My use case:
I want the batteries to stay reserved for backup (e.g. for grid failure), but during the daytime, I want to use solar power for self-consumption, without discharging the battery much.
So I’m using “Optimize for Battery Life” mode with Minimum SoC = 95%.
The problem I’m facing is this:
• At sunset, when solar stops and loads are still running, the battery slowly discharges down to 95%, then the BatteryLife State becomes “Active”, and battery discharge is disabled (as expected).
• However, next morning, when the battery recharges to 100% with solar, it remains stuck in “BatteryLife Active” and discharge is still disabled, even though SoC is full and there is solar available.
• Self-consumption doesn’t resume until I restart the system or manually tweak the SoC.
I believe this is a bug or limitation in how the BatteryLife logic clears itself.
So my question is:
Is there a way to make BatteryLife mode automatically exit the “Active” state after the battery has fully charged again (or based on some logic), so that self-consumption can continue without needing a reboot?
Please read section 6.2 on batterylife in the ESS design manual and it correct intended operation and configure your system accordingly. If your batteries are never actually discharged, it simply does not make sense to use it. Also, don’t hesitate to experiment with “keep batteries charged” as PV will be used when available and it may solve your dilemma. It will however consume grid to maintain the SOC. Finally, setting a 95% SOC in ESS will also work so I’ll leave you with that.
