Valuable energy on our doorstep: supplies of locally produced, eco-friendly natural gas play an important economic role, among their many advantages. RAG has been producing natural gas at fields in Austria for over 50 years.
Austria’s gas reserves play an important part in security of supply. In addition, gas production is a major growth driver for the economies of the regions where it takes place. About 15 % of the gas required by Austria is produced domestically. The remaining 85 % is made up of imports from the CIS and other countries. RAG contributes about 45 % of domestic production.
Gas is vital to industry, district heating and power generation.
RAG has been producing natural gas at fields in Lower Austria, Upper Austria and Salzburg for over 50 years, and today operates about 200 gas wells.
Supplies of locally produced, environmentally friendly natural gas play an important economic role, among their many benefits. We know exactly where the gas comes from, and that it is produced and transported according to the strictest environmental and safety standards – and this reduces import dependence. Currently, Austria meets about one-sixth of gas demand from households, industry and power stations with domestic output.
The biggest gas discovery in RAG’s history was the 17.5 square kilometre Haidach field, near Strasswalchen, struck in 1997; today it is Austria’s largest gas storage facility, with a capacity of 2.6 bn cu m.
When a new gas field is identified by a 3D seismic survey and is developed, first a production string, reaching down to the bottom of the reservoir, is inserted into the production well, once it has been cased and cemented. For the gas to flow into the well from the reservoir, the casing and cement must then be perforated. A so-called “Christmas tree” that closes off the well is installed at the surface.
A downhole safety valve in the production string prevents the uncontrolled release of gas. The natural reservoir pressure, which can be several hundred bar, lifts the gas to the surface, where it travels from the wellhead to the treatment plant via a high-pressure pipeline. Depending on the reservoir type and the pressure depletion, anything up to 99 % of the natural gas in place can be recovered. The flow rate declines over time, along with the reservoir pressure. Because of this, additional production wells are required later in the life of a field to maintain the level of overall output.
Before the gas can be fed into the supply network it has to be processed. First, the produced formation water, liquid hydrocarbons and solids are separated out in drying plants. The remaining water vapour is then removed from the gas using glycol or adsorption agents. Finally, the pipeline-quality natural gas is fed into the network.
“Natural gas is by far the most environmentally friendly conventional energy source. It can be safely stored in very large quantities, and is ideal for transportation in existing underground pipeline infrastructure. Gas is a key factor in maintaining security of supply at all times.”