The planned network of underground storage facilities will help optimise the use of gas for export and domestic consumption, said the National Iranian Oil Company (NIOC). French and German companies are working on the initial stages of the ambitious scheme for NIOC. The first two projects will together cost more than $200 million. Sofregaz of France is in the final stages of a feasibility study for NIOC to convert the Sarajeh gas field near the holy city of Qom into a gas storage facility with a capacity of at least 1 billion cubic metres.