**3.4 Review of 20 years of research at Soultz**

About 40 PhD theses have been written on the Soultz project in the last 20 years together with about 200 publications in international journals between 2001 and 2008. With this scientific background and the current production of electricity (1.5 MWe), the Soultz site is now a world reference for EGS. It appears that cooling 1 km³ of rock by only 20°C (initial temperature around 160-200°C) liberates as much energy as the combustion of 1 275 000 tons of oil and thus saves as much non-renewable fossil fuel (SoultzNet, 2011).
