As a committed player in the energy transition, Storengy offers its industrial clients throughout the world innovative solutions in energy storage. In France, Germany and the United Kingdom, Storengy designs, develops and operates three types of underground natural gas storage sites. Let’s explore a salt cavern storage site together!
During periods of low consumption, usually in summer, the gas is transported to the storage site through pipelines. The entering volume is measured and the gas is compressed in compressors. Then, it passes through a manifold. This is a set of pipes equipped with valves to distribute the gas to the buried pipelines which lead to the different wells located around the plant. To guarantee the safety and containment of the gas, the wells are systematically equipped with protection devices at the surface and underground. These wells are fit with metal pipes with a diameter of about 10 centimetres leading to caverns created artificially by injecting fresh water into deep salt layers which are totally impermeable and located at a depth of 500 to 1,500 m. The pressurised gas is injected through these wells to the caverns, which thus constitute storage facilities.
During peak consumption periods (in the winter), the gas is withdrawn from the caverns. It naturally rises into the well, reducing the pressure inside the cavern, and circulates through the buried pipelines towards the manifold once again. It is then subjected to a treatment linked to its underground stay, a dehydration process to remove the water it may contain. This “withdrawal water” is collected for treatment. In some cases, if the gas pressure is not sufficient to supply the transmission network, it needs to be compressed. For safety reasons, it is odorised and its quality is monitored in a laboratory. After measuring the outgoing volume, it goes into the transport pipelines.
All operations are remotely controlled from a control room. Thanks to their large capacity and their local anchorage, salt cavern storage sites ensure a reliable and continuous supply of natural gas throughout the year. They are indispensable to cover the necessary needs during winter consumption peaks and guarantee a territory’s security of supply.
And for the future, Storengy is already thinking about renewable gas storage in its caverns to support the energy transition.
