From crude oil to geothermal power

The energy comes from a former crude oil reservoir 1,100 meters underground in which 22,000 liters of water per hour circulate within a closed loop. “The decommissioned production site “La44” is one of 75 wells operated by our company here in the Landau region,” Dr. Thomas Ruttmann, Head of Wintershall’s operations at Landau, explains. However, technical modifications will have to be made before the crude oil well can be used for geothermal power: in future the heated water will be pumped to the surface via the tubing string at “well La44”. A heat pump and four heat exchangers will then supply the leisure pool, which is just 500 meters away, via a district heating pipe. “This cooperation will provide us with over a million kilowatt hours of environmentally friendly energy a year,” Thomas Hirsch, Managing Director of Stadtholding Landau in der Pfalz GmbH, the operating and holding company of the town, explained.
Since Landau is situated in the Upper Rhine Plain, it offers ideal conditions for generating geothermal energy. “With deep drilling, the temperature in-creases by an average of 4.7 degrees every 100 meters”, Dr. Ruttmann explains. He points out that this is considerably higher than the average increase in temperature of three degrees per 100 meters elsewhere. “That’s why there are a relatively high number of geothermal projects in the Landau region compared to other regions.” In order to develop former crude oil well La44, the three shareholders of the current concession, ExxonMobil Production Deutschland GmbH (EMPG), Internationale Tiefbohr GmbH & Co. KG (ITAG) and the wholly owned BASF subsidiary Wintershall, have joined forces with Lan Tec GmbH, a subsidiary of EnergieSud-west AG. The company specializes in the use of renewable energies and already operates several district heating networks in Landau in the Pfalz region.
Landau is home to the biggest crude oil field on the Upper Rhine Plain. The crude oil field is made up of eight blocks in which almost 200 wells in total have been drilled. The field was discovered in 1955 with the well “Landau 2”. Production of crude oil started in the same year. Overall more than 4.3 million tons of crude oil have been produced in Landau since then. The BASF subsidiary Wintershall holds a 50 percent share in the concession and also took over as operator. In addition to supplying the water park, the production operations in Landau currently use more than 13 million kWh of geothermal heat energy by treating the reservoir water. The energy generated this way is equivalent to the average consumption of over 350 households. With each household in Germany responsible for CO2 emissions of around 13 tons per year, this means a reduction of more than 4,500 tons of CO2 per year.