[Dynamic ESS] Add SOC level, below which NOT TO SELL energy to grid, but only support AC loads

Q&A and troubleshooting DESS
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That is great news! Regarding the implementation, I strongly suggest moving away from the ‘DESS Min SOC’ terminology for this feature. In the Victron ecosystem, ‘Min SOC’ is synonymous with battery protection and discharge floors.

A much clearer name would be ‘FeedIn SOC’ of ‘Trade SOC’. This name immediately identifies the threshold as a ‘gate’ for exporting energy, rather than a safety limit for protecting the battery.

Here is how the ‘ideal’ Green Mode should function using this ‘FeedIn SOC’ limit:

  1. Storage First (Below FeedIn SOC)
    The system treats the battery as the absolute priority. If the current SOC is below the user-defined FeedIn SOC (e.g., 90%), all excess solar is routed to the battery. Grid feed-in is disabled. We are not ‘trading’ yet; we are building a buffer for our own security.

  2. Injection Only for ‘True Surplus’
    DESS should only plan to sell energy if the forecasted solar yield for the day is mathematically certain to exceed the FeedIn SOC (e.g., a ‘planned SOC’ of 120%).

  3. Strategic Overflow (Above FeedIn SOC)
    Once the FeedIn SOC is reached, that extra 30% ‘overflow’ can be injected into the grid during the most financially beneficial timeslots. Crucially, the core buffer (everything below the FeedIn SOC) remains untouched and off the market for the user’s security.

Why this is better than plain ESS
We don’t want to lose the ‘Smart’ capabilities of DESS; we just want to change the priority. We still want DESS to:

  • Predictively Charge: Use the grid to top up the battery during cheap ‘off-peak’ hours if it sees that tomorrow’s solar won’t reach the FeedIn SOC before the high-price peaks hit.

  • Predictively Discharge: Use the battery to cover heavy loads during peak-price windows to maximize savings.

Essentially, we want the Predictive Intelligence of DESS combined with the Storage Security of plain ESS. Right now, DESS is too optimistic—it gambles on its own forecast by selling early. A ‘Storage First’ logic using a FeedIn SOC ensures that even if the forecast is wrong or there’s an unexpected load spike, the user has their defined buffer as a hedge.

By making FeedIn SOC a configurable setting, Victron gives the user the power to decide their own balance between ‘Energy Security’ and ‘Trading Efficiency’ based on their local rates and seasonal weather.

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DESS trading stupid