Dynamic ESS

Dynamic ESS is designed to run without intervention: VRM builds the schedule, the GX device carries it out, and the only inputs are the values entered during setup. Node-RED makes it possible to go further, where an installation has conditions Dynamic ESS cannot know about on its own.

Node-RED is a flow-based programming tool included in Venus OS Large, a separate image type for the GX device. Not all GX devices can run it. For installation and requirements, see the Venus OS Large manual.

Node-RED runs on the GX device and can read and write the same values Dynamic ESS uses. It is widely used in Victron systems, and the Victron Community is a good place to find worked examples and ask questions. There are three broad ways it is applied.

Automating settings

Dynamic ESS settings can be changed automatically in response to local conditions. For example, a Node-RED flow can detect that the utility grid has failed and lower the minimum SOC so that more of the battery is available during the outage, then restore the original value once the grid returns. The schedule is still built by VRM; only the conditions it runs under change.

Supplying prices

Prices can be written to Dynamic ESS from a source other than those VRM supports. This also allows scheduling to be steered around known events: where the times of planned grid outages are published, the prices for those intervals can be set high, and Dynamic ESS then treats them as expensive and plans around them. Ready-to-use flows are available for some of these cases.

Supplying the schedule

Dynamic ESS can also run from a schedule prepared locally instead of by VRM. In this arrangement VRM no longer supplies schedules, and the targets must be written to the GX device by another process. A schedule can be retrieved from the Dynamic ESS API, adjusted, and then written back. While this is in use, Mode on the GX device reads Local.

Further information