In the first of Current±’s new webinar series, Elexon’s metering manager Iain Nicoll discussed Metering Behind the Boundary Point, a look at the P375 BSC modification.
In the Current± Briefings session, Nicoll highlighted the importance of allowing individual asset meters to be used for settlement purposes, and the challenges of implementing such a modification.
You can now watch the session below:
Given the influx of questions, there wasn't time during the webinar to respond to them all. So afterwards, Current± caught up with Nicoll to ask him some more of the audience's questions on how P375 works with demand side response (DSR), metering standards and the potential impact of electric vehicles (EVs).
Do you know if Elexon will raise the new modification to include Additional BMUs or does this need to come from industry? I note that P376 is covering both Additional and Secondary BMUs so will Elexon take it on themselves to make P375 and P376 consistent in their remit?
The scope of P375 was limited to the ‘Settlement of Secondary BM (Balancing Mechanism) Units using metering behind the site Boundary Point’ and, by association, Virtual Lead Parties. In terms of replicating the benefits of P375 for Suppliers and Additional Primary BM Units a Modification would be required and this would be required to come from industry (Elexon cannot propose Modifications to the BSC itself). However, the benefits can be achieved by Suppliers if they register as a Virtual Lead Party.
Please confirm that P375 WILL enable Supplier Serviced HH settled metering systems to participate at BM where asset metering (perhaps embedded at battery or EV charging facilities) is in place behind the Smets boundary meter
The P375 solution was developed for Half Hourly settled customers. We are currently looking at any issues installing a P375 Asset Meter behind a SMETS (Smart Meter Equipment Technical Specifications) Boundary Point Meter, around the areas of cybersecurity and regulatory requirements. We will update industry once the position is clarified. P375 proposed that Asset Meters could be installed behind any Half Hourly settled Boundary Point Meter, for the P375 solution to work the Boundary Point meter needs to be submitting Half Hourly data into Settlements. Until Market-wide Half Hourly Settlement is rolled out SMETS meters will be settled as Non-Half Hourly and would not be compatible with P375, unless the SMETS meter MPAN (Meter Point Administration Number) is elective Half Hourly Settlement as a Supplier Serviced Metering System. This would require agreement of the Supplier for a Change of Measurement Class from Non-Half Hourly to Half Hourly.
Will P375 apply to both domestic and I&C customers?
P375 was developed for Half Hourly settled customers as for the P375 solution to work the Boundary Point meter needs to be submitting Half Hourly data into Settlements. We are currently looking at any issues installing a P375 Asset Meter behind a SMETS Boundary Point Meter, around the areas of cybersecurity and regulatory requirements. We will update industry once the position is clarified. For Non-Half Hourly settled customers premises the P375 solution isn’t compatible.
If a customer builds up a debt with a VLP, how would this be managed?
That is something that would be handled outside of the BSC between the VLP and the customer. It isn’t an area that the BSC would be involved in resolving. We don’t envisage a situation where the VLP would be billing a customer through P375 so we do not believe this situation should arise.
Will VLPs need to consider vulnerable customers?
That isn’t something that would be mandated by the BSC. It would be the responsibility of the VLP to take that into account when entering a commercial arrangement with the customer.
If PNs are required for boundary points, does this present a situation where suppliers and VLPs would both be submitting PNs for same boundary point?
The VLP would submit a PN (Physical Notification) and what they delivered in any given Half Hour period would be taken into account on the Boundary Point Suppliers predictions, and their imbalance position would be adjusted accordingly.
Are PNs always required from VLPs for their Secondary BMUs (before P376 implemented)? Do PNs always need to be for the boundary point - can they be issued for asset?
PNs are always required from the VLP for their Secondary BMUs (Balancing Mechanism Units). When submitting the Final Physical Notification (FPN) to National Grid ESO, P375 will require a VLP to ensure that their FPN reflects the sum of metered data expected at a Boundary Point Metering System Identifier (MSID) Pair or Asset Metering System Identifier (AMSID) Pair, depending on what is registered in the VLP’s Secondary BM Unit.
P379 has been shelved - in part because Elexon felt that P375 enabled aspects of multiple supplier models. Could you talk about how P375 could enable multiple suppliers?
P375 doesn’t enable multiple Suppliers. It allows a VLP to use the option of Asset Metering in a Secondary BMU and enter the Balancing Mechanism independently from the Boundary Point Supplier. In the same way P344 allows VLPs to use the Boundary Point Metering System (MPAN) in a Secondary BMU and enter the Balancing Mechanism independently from the Supplier of that MPAN. Consultants CEPA (who were commissioned by the BSC Panel to carry out independent analysis of the P379 proposals) asserted that some of the desired outcomes from P379 could be achieved through other changes to the BSC, including implementation of P375.
Would energy from the COP11 meter not flow through the boundary point meter? In that case would the settlement at the boundary point need to be reconciled against the COP11 meter? Would this not mean that the bill and settlement would be affected contrary to Iain's assertion?
Energy imported or exported across the Boundary Point will be recorded by the Boundary Point Meter. Should a Code of Practice 11 (CoP11) Asset Meter be installed it will record energy imported or exported by the Asset, this will be seen and accounted for by the Boundary Point Metering System. All billing to the customer will be based on the Boundary Point Metering System. The P375 solution links that Asset Meter (via the AMSID) with the MPAN via the MSID Pair. This relationship is established when the AMSID is Registered. This allows the Imbalance position of the Supplier to be adjusted. Any Supplier billing the customer implications are resolved contractually between the Supplier and the customer as per the P344 and P354 solution.
How does P375 work with DSR or load management or time of use services available via DCC?
The P375 solution was developed for Half Hourly settled customers. We are currently looking at any issues installing a P375 Asset Meter behind a SMETS Boundary Point Meter, around the areas of cybersecurity and regulatory requirements. We will update industry once the position is clarified. If any DSR or load management service with the DCC would demonstrate the delivery of a Balancing Service on the SMETS Meter it could be used via P344 as a Supplier Serviced Metering System without the need of an Asset Meter. Should that not be possible the VLP would have to look at any clashes with other services available and in use by a customer to determine if P375 is a viable option at individual sites.
For sites which do split metering from the boundary, would this modification allow for independent generators to retrofit in import/export asset metering behind the boundary so that each site can have independent metering?
Yes they can. There are a couple of ways to do this. Currently, where the Licensed Distribution System Operator (LDSO) considers it appropriate to issue an MPAN to subdivide the site, you can apply for a Metering Dispensation (as per BSCP32) to install BSC compliant metering behind the Boundary Point Registered against an MPAN. This effectively splits the site up in terms of Settlement and the P344 option can be used by the VLP in a Secondary BMU, or the Supplier in an Additional BMU. This can also be done using the Supplier Volume Allocation (SVA) Shared Metering arrangements (BSCP550) without the need of a Metering Dispensation. The alternative that P375 offers is to install an Asset Metering System Registered against an AMSID which allows individual Assets behind the Boundary point Metering System to enter the Balancing Mechanism via a VLP in a Secondary BMU.
What metering standards will apply to the specification of meter performing the AMSID role?
The Asset Metering Equipment must meet the minimum requirements for the Asset Metering Type (these types are split based on the rated capacity or maximum demand of the circuit) specified in CoP11. Any dedicated energy meter would be compliant with the Measurements Instrument Directive or the IEC 62053-## series (e.g. 62063-21).
Depending on whether it is compliant with the existing BSC CoPs (1, 2, 3, 5 and 10) it may also require completion of compliance testing under BSCP601 for Asset Meters. Any other dedicated meter type (e.g. power meters, transducers etc) are required to meet a recognised national or international standard, for example IEC 61557-12 (Power metering and monitoring devices). Asset Metering Type 5 is for the metering devices embedded within products, such as EV chargers, and while we await a recognised international standard to be developed we have specified the minimum criteria for them. The latter two always require completion of the compliance testing under BSCP601 for Asset Meters. It should be noted that for an Asset Meter to be approved there has to be at least one Half Hourly Data Collector or Asset Metering Half Hourly Data Collector that has completed Protocol approval for that Asset Meter.
How would this work if a PAYG meter is at the boundary point?
The P375 solution was developed for Half Hourly settled customers. We are currently looking at any issues installing a P375 Asset Meter behind a SMETS Boundary Point Meter, around the areas of cybersecurity and regulatory requirements. We will update industry once the position is clarified. PAYG was considered by the P375 workgroup and the VLP members felt the risk of a PAYG customer with an Asset Meter installed being disconnected at the time the VLP was delivering a Balancing Service was minimal due to the number of sites being aggregated at that level and of those only a percentage would be PAYG. It was also felt the risk would be on the VLP to manage.
Could Elexon confirm if D/C metering will be acceptable as an asset-meter for P375 (provided it complies with the data requirements)?
The DC option is limited to Asset Metering Type 5 which is a meter embedded within a device. For any type of proposal that is of a much larger scale where stepping current and/or voltage down is required we have limited it to AC in section 6.2 of CoP11 by limiting it to IEC 61869-2, -3 and -4 standards.
Currently this prevents the use of d.c. step down techniques (without a Metering Dispensation (as per BSCP32) subject to it being approved). At the time we drafted CoP11 there was no standard for DC energy meters. The International Electrotechnical Commission (IEC) have been developing one that is currently out for public review (IEC 62053-41. Electricity metering equipment (DC direct current)).
Again you could get round that via a Metering Dispensation (subject to being approved). Any Metering Dispensation would have to account for the losses in the inverter. If you were trying to split the site for Settlement and billing purposes (i.e. differencing being used for allocating energy between PV and Battery) there would need to be an approved meter for the DC as any billing meter needs to be approved either by MID (Measurement Instruments Directive) or the BEIS Office for Product and Safety Standards. For DC meters and devices used to step down current and/or voltage to be included in CoP11 a Change Proposal would need to be raised as per BSCP40, should amendments be approved this would negate the requirement for a Metering Dispensation.
Eventually EVs will replace cars. Looking at 1/3rd on charge over a Winter evening (c. 2040) shows a possible DR modulatable resource c.80GW, assuming domestic charging. Even 10% of this is useful. Will P375 allow modulation or recording of services from domestic EVs on the 230V system, using DR?
P375 was designed to include all technologies for an Asset delivering a Balancing Service. The definition of Dispatchable Asset in CoP11 does define it as ‘generation or a demand that can be switched on, off, or modulated as required’. We’ve put a framework in place for the minimum requirements for metering in CoP11 and how to get that data into Settlement, as well as the processes Parties and Party Agents need to follow for Registration, Meter Operations and Data Collection. So long as the metering solution is compliant with CoP11 and approved via BSCP601, and data can be submitted into Settlement in a Half Hourly format (either directly from the Asset Meter or via a software solution) it can be used.
Will COP11 relate to aggregated loads eg. EV DR services? Individuals likely 7 or 11kW
Individual Assets can be aggregated up. This can be via multiple Assets having an Asset Meter and the output being aggregated or a number of Assets sitting behind a single Asset Metering Point.
Can a site have multiple Metering agents for meters at a site?
There is no requirement in P375 to appoint the same Agents at all Boundary Point and Asset Metering Points.
Any Agent would have to be either a Qualified Supplier Volume Allocation (SVA) Half Hourly Meter Operator Agent or an Asset Metering Meter Operator Agent (AMMOA)., The AMMOA role is limited to only being able to be appointed for whole current Asset Metering Type 4 (Metering of energy transfers with a Maximum Demand of up to (and including) 1MW) and Asset Metering Type 5 (Metering (embedded within another device) for energy transfers with a Maximum Demand of up to (and including) 100kW) installations.