Energy storage: how does it work?
A concrete or steel tank, called an accumulator, is installed near the place where the energy is produced. If necessary, it stores this energy, which it will later deliver to neighboring buildings or to the heating network to which it is connected. Its volume is sized according to technical feasibility: from a few dozen to several thousand cubic meters! When the heat consumption of the users is lower than the production, the accumulator stores hot water. It gives it back during peaks in heat demand. Depending on the size of the storage, the energy reserve can be used to supply customers from a few hours to several days. This is a way to improve the use of renewable and recovered energy, and to reduce the overall carbon footprint.
Energy storage: a tool for flexibility
Because it makes it possible to decouple energy production and consumption, storage is a powerful lever for environmental and economic optimization. In Brest, for example, a solution devised by Dalkia makes it possible to retain the heat released by the waste-to-energy plant. The hot water passing through the heating network is stored in a 1,000 m3 storage tower. But why do we store this hot water? To meet the peak consumption of the buildings connected to the network. For example, in the morning, when the heating system is restarted, the heat is available immediately: this gives us greater flexibility and energy savings!