The evolution of the CO2 concentration in the atmosphere is now widely acknowledged
as a major concern for the future of the Earth climate.
In order to stabilize the CO2 content below 500ppmv several strategies will have to
be employed during the 21st century.
Energy efficiency, CO2 capture and storage, nuclear energy and renewable energies
will share the overall efforts, to a different extend.
Among all renewable, geothermal energy is now ranked 3rd after hydropower, biomass
and wind energy. Interestingly, geothermal can produce either heat or power on a
continuous basis. Despite this interesting situation, the growth rate of geothermal
installed capacity is not so high than the ones of wind energy or biomass. This is
probably due to the fact that the thermal and permeability properties of underground
geological structures are difficult to assess leading to somewhat high capital risk
of many geothermal projects. Even if this knowledge could be greatly improved, the
spatial distribution of high grade (good temperature, good permeability) geothermal
resources is rather scarce.
This is the reason why the development of Engineered Geothermal Systems (EGS) is so
important to allow a rapid growth of heat and power production in a large percentage
of the continents.
The most important gaps to be fulfilled before achieving this growth are probably
linked with the reduction of drilling costs and with the complete mastering of the
creation and the maintenance of the underground heat exchanger.
The ENGINE Coordination Action will allow European research organizations to share
their expertise with industries and public entities. Many crucial aspects of the
development of EGS will be presented during this launching conference.

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