Submetering: Challenges and Opportunities for its Application to Flexibility Services

Flexibility can be defined as the ability of energy resources and consumers to change or adjust their injection or withdrawal to/from to the electricity system in response to an economic signal (market prices, day-ahead and intraday markets or network tariffs), to provide services to system operators or to the markets [6] [9]. A CAP means the point referred to in the Connection Agreement signed between the customer and the systems operator and is the point electrically closest to the connecting system operator’s grid. In some cases, the “main meter” at the CAP is also known as “regulated meter”.

Compensation effects include the financial compensation between the independent aggregator (FSP) and the supplier.

Smart meters have a granularity equal to the Imbalance Settlement Period (ISP) granularity for energy settlement, which should converge to 15 min in all European scheduling areas (European Commission, 2017). Smart metering systems rolled out after July 5, 2019, should also offer standardized or remote near real-time interfaces for home energy management, demand response and other services as defined in Art 20 of Electricity Directive (EU) 2019/944 [14]. Near-real time means non-validated metering and consumption data provided continuously by a smart meter or a smart metering system in a short time period (usually down to seconds or up to the ISP). In many Member States, system operators have started initiatives to make these interfaces available to involved actors (see, e.g., Dutch NextGen Smart Metering initiative, Austrian Digitale Kundenschnittstelle, German Smart Meter Gateway, French Linky interfaces, and Italian In-home PLC-based Sinapsi).

In energy efficiency programs, submeters are part of the energy monitoring systems, which include the specific energy meter, a communication system with the cloud and an interface to monitor the consumption. They include a current transformer and a communication connection (e.g., RS-232) and are based on common protocols such as Modbus and TCP. Some submeters also include a small display to monitor the real-time data.

The definition of DMD in [5] does not prevent the use of their data for other processes, for instance, in local energy communities.

In the scope of flexibility services, the baseline is the estimated counterfactual position used to calculate the delivered flexibility from an FR [23].

Future European Regulation implementing flexibility services will allow for multiple FR providing flexibility services behind the same CAP [28].

Submeter data does not include flows from other devices or electricity losses behind the CAP such as from cables, transformers, DC-AC inverters, auxiliaries, or other equipment. Some MSs have initiated projects to make near-real time data from smart meters more easily sourceable for actors in need of that (see Austrian Digitale Kundenschnittstelle, French Linky adapters, Italian In-House PLC Sinapsi adapter or Dutch NextGen Smart Meter project). On a European level, Project EDDIE (European Distributed Data Infrastructure for Energy) (https://​eddie.​energy) is providing a component called Administrative Interface for In-house Data Access (AIIDA) to achieve a uniform European interface for both submeter, but primarily P1 interface data under sovereign control of the final customer and in a non-discriminatory manner.

All listed processes might be defined at FR level. However, in the future implementation of flexibility services, some of these processes might be performed at FR portfolio level (group of FR) or at the CAP level. Anyway, descriptions do not change.

As an example, an IBM Independent Audit on Belgian TSO Elia’s Transfer of Energy process and systems states that exactly this measurement at the boundary point is an important shortcoming that is just acceptable in status quo, with very low volumes and very low numbers of connected assets. It identifies the need for correction in the future. However, measurement strategies of other System Operators are—currently—similarly compromised [34].

Interoperability refers to the ability of communication networks, systems, devices, applications, or components to interwork to exchange and use information and perform their required functions (Electricity Directive (EU) 2019/944).

Smart Applications Reference Ontology (SARED) is a shared model of consensus that facilitates the matching of existing assets in the smart applications domain. Other matured open data models are being promoted by different actors, to favour real-time streaming exchanges among different flexibles devices, such as the European Customer Energy Management Data Model (S2) standard EN 50491–12-2.

In [36], “metered data administrator” means a party responsible for storing validated historical metering and consumption data and distributing these data to final customers and/or eligible parties.

The MASS specifies that all the measurements of Local Frequency, Generation Amount and Load Amount “must be measured at, or close to, each relevant connection point and summed to calculate the Aggregated Generation Amount or Aggregated Load Amount. Where any part of an Aggregated Ancillary Service Facility shares a connection point with a variable load or generating unit, it is the gross active power flow to or from the relevant plant that forms the aggregated response by the Aggregated Ancillary Service Facility and must be measured directly.”[49]

Transpower, Instantaneous Reserve Ancillary Service Schedule, 27 September 2023, available from [50]; see §5.3.

See §3.9.4(i) and Schedule.

In the UK, the administered Balancing and Settlement Code (Elexon) performs statistical monitoring to identify if some resources that participate in the balancing markets are not acting independently of other assets onside.

The Nordic Regulators (NordREG) includes the National Regulatory Authorities (NRAs) from Denmark, Finland, Norway, Sweden, and Iceland.