We take a look at the Corrèze Resilient Grid project which has deployed renewable production and energy storage to create a microgrid in a rural area.
In Corrèze, southwestern France, the rural Nespoux hamlet is nestled in an isolated and mountainous location, in an area not blessed with underground power lines. As a region that suffers the effects of climate and experiences periods of intense weather, fallen trees on medium voltage lines are not uncommon and residents are regularly subjected to the effects of issues on the electricity grid.-
When power to the area is lost, so too are the supplies of drinking water, phone communication lines and access to the fire safety emergency call centre. To compound these issues, the access challenges for this particular location mean that it can take several hours or even days for repair teams to make their way through and restore power.
Creating a resilient microgrid in a rural area - using renewable production and energy storage
Since 2018, the Corrèze department has undertaken an Ecological Transition program to help improve living conditions and provide assured power supplies.
The Corrèze Resilient Grid project is part of this program, managed in partnership between the Syndicat de la Diège -, an electricity distribution authority in charge of over 65 municipalities - and Enedis - the French public service grid operator.
After a 3-year study and several exchanges on the subject, Enedis, the Syndicat de la Diège and the Department of Corrèze decided to initiate an experiment into an innovative solution in 2019.
This project is part of a global territory approach to the development of smartgrids in rural areas which tests smartgrid architecture in real-world conditions and repowers homes using the inhabitants’ own PV installations – demonstrating that it is possible for people to work on a disruptive concept in an evolving electric grid.
What does the system comprise?
3 PV generating installations over 1200m² of stable rooftops have been installed within the hamlet. In addition, the stable and hamlet
residents have been equipped with “Linky” in order to measure the electricity produced by the photovoltaic panels as well as to measure the electricity consumed. Finally, a battery energy storage system (BESS) has been installed to enable the surplus PV production to be stored and consumed when working in islanding mode, in case of grid loss. The ESS from Socomec includes a storage converter, a lithium-ion battery, a control-command cabinet (MCM) and a grid connection cabinet.
How does it work?
Just 3 minutes after the outage event, the grid circuit breaker (CBG) opens and separates the public distribution grid from the Nespoux microgrid.
At that same moment, the BESS and the PV enable the power supply of the microgrid, so that the supply of electricity to inhabitants and critical installations is secured.
In parallel, Enedis teams join forces in order to make repairs as quickly as possible.
The result? Power is restored to 5 houses, 1 fire department antenna and 1 drinking water pumping station.
What’s next?
Elodie Hestin, Socomec comments; “The success of this project means that it is now possible to carry out additional testing in order to better understand usage, as well as to replicate and roll out the approach more widely. In addition, the installation can evolve. The storage system could be used to perform other services during on-grid operation when the energy strorage system is not being used – to provide an EV charging station, PV self-consumption maximisation or peak shaving, for example. It is an exciting time in renewables and storage, and the future for challenging locations and rural areas is certainly looking bright.”