There are probably not too many climate activists in the small village of Ampfing in Southern Germany, as the information plaques and monuments dedicated to the local history of oil production look unspoiled. Can you even imagine living on Mobil Oil Strasse – Mobil Oil Street? It is possible in Ampfing.
The village appeared on the exploration radar in the 1950’s, when the results of a seismic survey suggested the presence of a valid closure at Eocene level – at a depth of around 2,000 m. Subsequent drilling of the Ampfing-1 well in 1953 proved the presence of oil shows, but it was the second well that brought the success that was hoped for. To mark the discovery, the sandstone in which the oil was found was named the Ampfing Sandstone, which is still known as a stratigraphic name today.
Many more wells were drilled, and as gas was also found, also in surrounding areas, a nationwide gas distribution system was built. This meant that Bavaria could say goodbye to gas generated from coal, which can in some ways be seen as the first step in the energy transition. Over the years, around 26 million barrels of oil and 13.9 billion cubic meters of gas were produced from the Bavarian oil and gas fields together.
Production from most fields started to become marginal in the 1980’s and 1990’s. Ampfing ceased production in 1987, and most followed in the decade after. That was not the end for Ampfing though, as a new attempt to revive production was made in 2016 when RDG – a spin-off from RAG Austria – drilled a new well into the field. A 3D seismic survey and more wells followed, but the production test in 2020 ultimately put a stop to further development as it was regarded uneconomic in the end.
Yet again, it was not the end of Ampfing’s link to the deep subsurface. ONEO – formerly RDG – now aims to produce geothermal energy from the Upper Jurassic Malm that can be found beneath the Ampfing sandstone. To that end, the company aims to deepen one of the wells recently drilled into the field, and the completing of a new one.
A feasibility study has shown that between 19 and 24 MWth could be produced from the doublet, which is certainly a good amount. This is partly thanks to the relatively high geothermal gradient of around 40°C per km and the fact that the Malm carbonates tend to have good porosities and permeabilities in Bavaria.
