Intelligent and alternative connection agreements
The principle of “intelligent connection agreements”, or “alternative connection agreements with power modulation”, is well known: this type of connection makes it possible to increase the capacity of networks, for example for decentralised energy ressources (DER), in exchange for partial and occasional curtailment of the generation installation.
From the producer’s point of view, this is equivalent to accepting a limited loss of earnings in return for a faster and cheaper connection to the grid. More generally, as the smartgrids-cre.fr website explains, it is “a way of connecting more production facilities without having to make costly new investments in the existing network”.
Today, smart connection offers are only offered by System Operators on a selective basis, and in particular only to high-power producers, to the exclusion of those connected to the low-voltage network.
Implementing Alternative Connection Agreements at Low-Voltage level
The Grid ExpanDER software, developed by Roseau Technologies with financial support from Ademe, aims to massively increase the use of smart connections by enabling this technical solution to be implemented in low-voltage networks, potentially for hundreds of thousands of small-scale production facilities!
To achieve this, the software relies on existing smart meters, using them not only as sensors to regularly assess the electrical state of the network and identify the periods when capping is necessary, but also as telecoms gateways for relaying partial curtailment instructions to flexible production facilities.
In the heart of the Maurienne valley in Savoie, Soréa is currently testing the Grid ExpanDER solution on a low-voltage feeder in the commune of Saint-Julien-Mont-Denis, serving a flexible production facility with a capacity of around 40 kWp.
On a sunny day, as the voltage level in the grid gradually rises, the smart meter detects that the maximum voltage threshold may be exceeded. Partial shedding setpoints are automatically calculated and transmitted to the inverter. The correct application of the clipping setpoint can be checked using the profile of the power injected.
This pilot project, which has enabled the technical solution to be validated in an operational environment, also highlights the remarkable capacity for innovation of Local Distribution Companies, whose flexibility and responsiveness are extremely valuable when it comes to experimenting with innovative technologies.
Our latest publications on Alternative Connection Agreements:
A dynamic voltage controller for LV grids based on flexible PV systems and the smart metering infrastructure
A. HAMDAN, F. CADOUX, B. VINOT – 27th International Conference on Electricity Distribution (CIRED 2023)
Non-firm grid connections for low-voltage generators: a case study
L. MULLER, F. CADOUX – 27th International Conference on Electricity Distribution (CIRED 2023)
This project is supported as part of the Programme d’Investissement d’Avenir (PIA) operated by ADEME.