Bulgartransgaz inks another contract on Chiren storage’s expansion

Gas Materials 21 January 2023 10:09
Baku, Azerbaijan Trend News Agency
Bulgartransgaz inks another contract on Chiren storage’s expansion

Bulgartransgaz EAD and DZZD Tech Energy Expansion signed a contract for the supply of the necessary materials and equipment, construction and commissioning of "Expansion of Chiren UGS capacity - above-ground part", Trend reports via Bulgartransgaz.

The total value of the Contract with DZZD Tech Energy Expansion amounts to BGN 297,777,777.29 ($165,262,704.2), VAT excluded. The contract is co-financed by the European Union through the Connecting Europe Facility.

The total amount of the investment related to the expansion of Chiren is about BGN 600 million. Works on the storage facility expansion are envisaged to be completed by the end of 2024.

The project aims to increase the active gas volume up to 1 bcm (currently 550 mcm), increase the daily withdrawal capacity up to 10 mcm/d and the injection capacity up to 8 mcm/d. Currently the maximum daily withdrawal capacity is 3.82 mcm/d, and the maximum daily injection capacity is 3.62 mcm/d.

Bulgartransgaz EAD Executive Director Mr. Vladimir Malinov said that the increased storage capacity in the Chiren UGS will ensure the security of natural gas supply and will contribute to enhance the competition and the access to natural gas from alternative sources.

UGS Chiren was constructed on a base of depleted gas condensate field, discovered in 1963 in Northwest Bulgaria. During the exploitation period of the gas condensate field, 2.8 bcm of natural gas and 76.2 thousand m³ of gas condensate have been produced in total.

Operation of the gas storage began in August 1974 by transformation of the depleted gas condensate field into gas storage. So far, it is the singular gas storage facility in Bulgaria.

24 exploitation wells, a compressor station with a total installed capacity of 10 MW and other facilities required to secure the injection and withdrawal as well as to the quality of the stored gas are being operated in Chiren UGS.

The operational characteristics of UGS Chiren and its operating mode depend on the features of the Chiren geological structure, the petrophysical properties of the underground gas reservoir, the type of the artificial gas deposit, the type of the aquifer system and other factors.

The gas storage operation is cyclic, whereas the injection period starts in April and ended in October while the withdrawal period begins from November till the end of March.

The highest gas withdrawal from the storage for a season has reached 390 mcm, but in the last three years the withdrawal was within the range of 300 mcm, depending on the needs of the natural gas market in the country. The maximum withdrawal rate, reached during the gas crisis in January 2009 and maintained for two weeks was 4.2 mcm/day.