Community energy is a relatively recent concept that has been introduced globally and is gaining populary among European countries. It refers to a a wide range of collective energy actions that actively involve citizens’ participation in the energy system. In an energy community, a legal entity such as a cooperative, is set up between different stakeholders, which can interact as a single prosumer with the utility grid. The setting up of an energy community allows the members to share energy that is generated locally through renewable energy sources within the commity itself. This can help to better match the demand and renewable energy supply when taking into consideration a group of buildings, allowing for collective self-consumption. The European Union officially introduced the concept of energy communities as part of the Clean energy for all Europeans package.
The final Clean Energy Package contains two definitions of energy community: Citizen Energy Community and Renewable Energy Community.
According to the renewables directive, a renewable energy community is a legal entity which is based on open and voluntary participation, is autonomous and controlled by shareholders or members that are located in the proximity of the renewable energy projects that are owned by the legal entity. Shareholders or members can be natural persons, SMEs or local authorities. The primary purpose of the entity is to provide environmental, economic or social community benefits for its shareholders or members or for the local areas, rather than financial profits. Renewable energy communities are entitled to produce, consume, store and sell renewable energy, and share renewable energy within the community itself.
The electricity directive, defines a Citizen Energy Community in very similar way as the Renewable Energy community, which is also a legal entity that based on open and voluntary participation and is controlled by its members or shareholders. Its primary purpose is also to provide environmental, economic or social community benefits to its members or shareholders or to the local areas where it operates rather than to generate financial profits. The main difference is that this directive does not make it obligatory for the citizen energy community to generate energy only through renewable sources.
In order to enable autonomous operation of energy communities, micro-grid systems need to be set up. A microgrid is a self-sufficient energy system that serves a specific geographic area, such as a hospital complex, a business centre, a university campus or a neighbourhood. Distributed energy generation systems such as solar panels, wind turbines, combined heat & power, as well as conventional generators, are installed within the micro-grid to provide the energy supply. In addition, microgrids can include energy storage, typically from batteries as well as electric vehicle charging stations.
Energy communities and urban micro-grids have a number of advantages. These can provide a more reliable energy supply as well as lower energy costs, since energy is being produced locally instead of being distributed over long distances. Therefore network losses can be reduced significantly. Enabling energy communities provides flexibility and empowers the prosumers, thus involving them directly in the city decarbonisation process. A micro-grid system allows for collective energy self-consumption (e.g. in the case of a block of apartments or a group of buildings) and therefore helps to maximise the amount of energy the is self-consumed within the energy community. Micro-grids are also advantageous from the utility grid point of view since they can provide a number of services to reduce the stress on the grid infrastructure. The setting up of different micro-grids with renewable energy sources and energy storage will also help to cater for the gradual increase in the use of electric vehicles within cities. Last but not least, energy communities and micro-grids help to reduce the overall carbon footprint of the city.
