The ESO held its latest Balancing Programme event on November 28th. This is the last one before the Open Balancing Platform (OBP) launch in December. It detailed how the first release, specifically ‘bulk dispatch’, will improve how battery energy storage is used in the Balancing Mechanism (BM). This is essentially the first step to improving skip rates for batteries.
The Open Balancing Platform is on track for launch on December 12th
The ESO announced that they are on track for the launch of the OPB on December 12th. This will be confirmed in the Operational Transparency Forum on December 6th. The launch will bring ‘bulk dispatch’ functionality to the control room for two ‘zones’ covering batteries and Balancing Mechanism Units less than 50 MW in size (the small BMU zone).
The bulk dispatch functionality creates an optimized set of aggregated instructions to meet a much larger response and sends these to all BMUs in one go. Essentially, it turns a much larger ‘requirement’ shape into a series of BM dispatch instructions at the lowest cost.
Control room engineers currently have to do this process manually. This means they will spend much less time and effort sending instructions and instead focus on monitoring and reacting to system conditions. It also creates conditions where skips can occur, especially in time-pressured situations.
This means batteries will see an increase in the number of Balancing Mechanism dispatch instructions
Following the release, the control room will run bulk dispatch six times per hour for the battery zone, with each run envisaged to result in 25 to 50 instructions of 5, 10, or 15 minutes in duration. This is anticipated to provide between 200 to 300 MW of bulk response, up to a cap of 500 MW.
The small BMU zone will be dispatched four times per hour but with potentially more instructions. The ESO makes it clear that this will significantly increase the number of dispatches post-release. Batteries have averaged around 6.5 dispatches per hour, which may increase to a maximum of 300 per hour with bulk dispatch.
How this tool is used will still depend on how control room engineers grow comfortable using it. Because of this, improvements from the release of bulk dispatch will likely increase over time.
Further Balancing Mechanism updates will come in quarterly releases
The release in December represents just 5% of the functionality of existing systems. Quarterly releases will run until the summer of 2025 to migrate everything else into the OBP. Four of these, including the first release, are anticipated to bring substantial improvements to battery energy storage.
Spring 2024 - this release brings ‘fast dispatch’ and Balancing Reserve dispatch functionality. Fast dispatch will allow bulk frequency correcting actions, typically less than 10 minutes, to be designed and optimized quicker. This is expected to bring another step change for battery energy storage utilization.
Summer 2024 - the launch of Quick Reserve (BM only) and bulk dispatch of wind (which helps manage wind not following physical notifications).
Autumn 2024 - improved constraint management. This release contains mostly support tools rather than dispatch functionality.
Winter 2024 - implementation of new storage parameters allowing longer duration dispatch (removes 15-minute rule), a significant change for battery energy storage. This is a big release that allows non-BM functionality to begin to move to the OBP.
Spring 2025 - focuses on non-BM, moving functionality from the Ancillary Services Dispatch Platform (ASDP) to OBP. This includes API migration and the creation of other instruction types.
Summer 2025 - the release of non-BM Quick Reserve and Slow Reserve (BM and nonBM). It also shifts pumped storage dispatch to OBP. Following this release, all information and instructions are now in one place, and existing systems can begin to be decommissioned.
Other battery energy storage changes are in the works
The OBP will bring significant updates to how battery energy storage can be used in the Balancing Mechanism, firstly through bulk dispatch, then fast dispatch, and finally, the removal of the 15-minute rule. The first two will improve how the control room can dispatch many battery energy storage assets for most of today’s actions.
The final change, removing the 15-minute rule, requires much more than just a system change within the control room. It needs grid code modifications, the design of new dynamic parameters, and data flows by which these can be sent to the control room.
The event also included updates on other changes affecting batteries. It was confirmed that new guidance is expected imminently on MEL/MIL declarations to reduce the amount of data flowing to the control room. Separately, improvements to the systems handling this data are also being made by ESO and Elexon.
Ultimately, all eyes will now be on December 12th 2023 to see whether the Open Balancing Platform launches as planned and just how much this improves the utilization of battery energy storage in the Balancing Mechanism.