In July 2007 Wärtsilä received a major contract from MOL Hungarian Oil & Gas Plc to deliver compressor drives and auxiliaries for an underground gas storage in Szőreg, southern Hungary.
As a trial run the compression plant was injecting natural gas into the gas storage already in September 2009. The gas storage secures the energy supply in case of any interruptions in the gas supply system and also partly operates as a commercial storage facility.
Szőreg is linked to the domestic gas transport system and to the international gas transportation routes. Hungary has depleted oil and gas fields, which are most suitable for being transferred into natural gas storage facilities.
The plant is equipped with seven reciprocating gas compressors, five of these are driven by Wärtsilä 9L34SG gas engines and two electrical motors used for injecting natural gas into the gas storage facility.
The Szőreg-1 Safety Gas Storage has a total storage capacity of 1.9 billion cubic meters at a pressure of 182.5 barg. The compression station is controlled by a fully automated Wärtsilä WOIS system. In gas storage applications Wärtsilä gas engines enable a wide and dynamic operating range with maintained efficiency. The Wärtsilä SG engines operate in the speed range 525–750 rpm with constant torque.