Theoretical research and development work had already been under way in Switzerland
for 20 years in what was at that time still referred to as Hot Dry Rock geothermal
energy technology, when at the end of 1995 the Federal Office of Energy expressed
their interest in it as a potential component of a future new energy mix.
The result was the creation of the DHMA and subsequently the formulation of the Deep
Heat Mining programme. DHMA were further charged with managing the programme. In the
ten years since 1995 the necessary studies and investigations have been undertaken,
resulting in a positive verdict on the feasibility and on the potential usefulness of
implementing EGS technology in the Swiss context.
Multi-parametric data analysis, including socio-political aspects, led to the
selection of the city of Basle for a first pilot plant, with Geneva as the reserve
choice. For the necessary prestudies the Office of Energy provided seeding money,
with the understanding that the pilot plant itself would have to be financed by local
/ private organisations.
A plant has been conceived, sited within the area of the city of Basle, which at the
present state of the art, can only be designed in final detail upon completion of the
reservoir stimulation and generation and testing of the underground heat exchanger.
The target is a co-generation plant contributing heat to the district-heating network
and power to the electrical supply. A wide range of technical solutions have been
examined, one of which uses a hybrid (gas turbine plus ORC cycle) system for energy
The choice of site, the concept of co-generation and the decision to operate under
commercial pressures are parts of a concept to give the EGS hot fractured rock
technology the best chance of success.
During the past two years the financing of the new plant and the structure of
GEOPOWER BASEL AG have been worked out by the investors. In parallel, much effort has
been put into project preparation tasks and building up the structure of a project
team. All permissions to prepare and drill on the main site having been received in
the course of 2005, the site preparation, including power supply, water supply,
drainage and water return systems, have been undertaken. By the end of 2005 four
monitoring wells were ready for the installation of micro-seismic instruments. Two
additional wells will be ready by mid February. The operational and logistic
planning, and the design for the first deep well are largely completed.
Drilling is now programmed to start at the end of April of the current year.