question

Leon Backbier avatar image
Leon Backbier asked

Seeking Clarification on DESS Battery Management and Optimization Strategies

Hello Community,

I've been exploring the functionality of Distributed Energy Storage Systems (DESS) and I find myself a bit perplexed about how the system decides to load or unload the batteries. From my observations, it appears that the system prioritizes selling energy, whereas I expected its optimization to focus more on storing solar energy and inexpensive electricity for later use, selling any surplus energy as a secondary objective.

In my case, the system seems to use the batteries during peak load times but then quickly recharges them, which seems counterintuitive to what I expected. This behavior raises a few questions:

  1. Is there a specific logic or algorithm that DESS follows for deciding when to charge or discharge the batteries?
  2. Does the system prioritize selling energy over storing it for future use? If so, why is this the case?
  3. Are there any adjustable settings or configurations that allow users to prioritize energy storage over selling, or vice versa?
  4. Most importantly, is there comprehensive documentation available that explains the operational logic of DESS? I am keen on understanding the underlying principles and strategies for battery management in these systems.

I believe having a clear understanding of how DESS manages and optimizes battery usage would greatly enhance my ability to efficiently use the system. Any insights, documentation, or resources that could shed light on this matter would be greatly appreciated.

Thank you in advance for your assistance and knowledge sharing!

dynamic ess
2 comments
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

yvos avatar image yvos commented ·

Thanks for your question, this is exactly what I am expieriencing, the system is acting like te Wolf of Wallstreet in stead of Greta Thunberg. I do not have a answer but want to tell you what my opinion is, hopfully we get a good answer.

I would also like to see more adjustability in what the selling criteria are and under which conditions. I have shut DESS off because of this. And now with predictable low solar energy in the Netherlands I have a charge schedule active for 3 hours starting at 2 in the night. This is in the winter almost always the cheapest price window for buying. During the next 21 hours I can live out of the battery. Bought my energy at the lowest price and helping the grid to buy at night and not using the grid during day time. Everybody happy.

I think there should be more algorithems with different purpouses. I think for a lot of people the first objective of having a battery system is not earning as much of money they can but using energy in the most cleaver and environment friendly way. Most of the times this is also the more cheaper way.

For a summer scenario I would like to store as much as solar energy in my batteries to live for 24 hours of it. if there is exces predicted, the system should sell it for the highest price. But not sell the whole enregy storage so that i have to buy again in the same 24 hours. That is a waste of energy production in favor of making money.

1 Like 1 ·
teemischer avatar image teemischer commented ·

Thanks, YES, exact same problems here as well: I don't want to feed in anything in winter. Everything should be stored for later consumption.

What I would expect: Work exactly like the existing ESS, but add dynamic purchasing. No other odd behaviour.

I have already emailed @Dirk-Jan Faber (Victron Energy) about this and he promptly replied, my impression from the reply was that Victron has hopefully understood this requirement and is working on it. This thread here in the forums shows that the feature request is not a corner-case but a standard behaviour of Dynamic ESS which many (all?) users would expect.

For now I will keep DynEss switched off and use other means of charging based on dynamic prices. Here is a list of alternatives which I have found working well so far:

- https://gbboptimizer.gbbsoft.pl

- https://github.com/christian1980nrw/Spotmarket-Switcher

- Just use fixed time charging schedule (as described by @yvos below)

There are also more solutions available but I have not tried them personally.

My request to Victron would be to just implement this charging logic in DynESS so we don't keep the community busy with building their own solutions.

1 Like 1 ·
1 Answer
Leon Backbier avatar image
Leon Backbier answered ·

strange that no one from Victron is picking upo this thread. Should i poist elsewhere?


2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.