Defining Optimal Configurations of Geothermal Systems Using Process Design and Process Integration Techniques

In the perspective of increasing the share of renewable energies to mitigate global warming and to respond to fossil resources depletion, the use of geothermal resources for the polygeneration of energy services has gained interest and is expected to know an important development in the future. Some of the major issues linked with the use of geothermal energy concern the increase of the efficiency in the conversion, the increase in their economical profitability and the minimization of their generated life-cycle environmental impacts. Several studies propose optimization strategies for increasing efficiency and costeffectiveness of geothermal power generation (Desideri and Bidini (1997); Hettiarachchi et al. (2007); Franco and Villani (2009)). However, none uses process integration techniques, nor includes the potential exploitable geothermal resources or the systematic possibilities of heat cogeneration in the optimization procedure. A systematic methodology including process design and process integration techniques would allow for identifying the optimal configuration of geothermal systems, but has to consider simultaneously the exploitable geothermal resources, the potential conversion technologies and the seasonal demand in energy services. The bases of such a methodology are presented in Hoban et al. (2010), but without considering a systematic multi-objective optimization procedure.