The future of geothermal energy : Enhanced Geothermal Systems

It is an innovative concept in deep geothermal that is being developed around the world and that will increase global geothermal capacity significantly.
EGS means "Enhanced Geothermal System". The concept is to use the heat of the water contained in the naturally fractured rocks. Temperature and heat generation increases with depth. The Earth's crust contains a considerable amount of energy that is continuously supplied by the geothermal heat flow coming from Earth depth.

Geothermal reservoir basics

In its natural state, a geothermal field is defined by three key elements: heat, fluid, and permeability. The fluid can be water, steam, or a mixture of both.
An EGS geothermal reservoir is a volume of hot and naturally fractured rocks but whose permeability could have to be improved to produce the geothermal fluid. To make it economic, the reservoir has to be stimulated by reinjecting the water that was pumped there. This process increases the volume of natural fractures creating sufficient permeability to commercially operate the geothermal field.

Deep geothermal EGS power plant concept / Hot Fractured Rocks
Water is pumped from a naturally fractured cristalline rock reservoir and reinjected