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St. Gallen project at crossroads with insufficient flow rates

St. Gallen project at crossroads with insufficient flow rates Drilling rig on site in St. Gallen, Switzerland (source: Webcam Project website, Aug. 7, 2013)
Alexander Richter 14 Feb 2014

Following disappointing results of production tests with insufficient flow rates, the geothermal project in St. Gallen, Switzerland now stands at crossroads on the future of the project.

In a release yesterday, the geothermal power project at St. Gallen in Switzerland has announced the results of its production tests of the well drilled in the city.

Due to the results, the further development of the project is now in doubts. The project already faced the big challenge of gas inflow into the well, but mostly of concern was a seismic event. Nevertheless the project decided to move forward.

The production tests of October 2013, now provided important sets of data on water, and gas flows. All in all four production tests were realized and the well was closed.

The production tests proved water in the well, but with insufficient flow rates. The achieved flow rate on a constant basis was at 5.9 l/s with a maximum of 12 l/s. With 145 degrees Celsius the achieved temperature was higher than estimated prior to drilling.

The project also provides some indication on the gas inflow with rates of over 5,000 Nm3/ hour, which – so the project – represents the hourly gas usage in the city of St. Gallen on an average fall day.  But there are no indications on the total gas volume available.

As a result of the low water flow rates and the inflow of gas, the project developer sets a big question mark on the continuation of the project. The potential seismicity risk increases the difficulties going forward.

The project now considers three possible scenarios, which differ from the initial plans for the project.

Until mid of this year, the project will now explore the technical feasibility going forward, but also the financial, political, legal and administrative framework. This includes the possibility if the project could qualify for the promised risk mitigation of the Federal State of Switzerland in case of insufficient well output. This would allow the project to recover around 50% of the accepted drilling and resting costs of maximum CHF 24 million ($27 m). So far the project has invested around CHF 44 million ($49 million).

For details on the project see the project website at: http://www.geothermie.stadt.sg.ch/aktuell/uebersicht.html

Source: project newsletter