8KUE0N33 - Stockage géologique d'énergie

OUI

Course: Geological storage of energy

1. Heat storage in aquifer (geothermal storage):

Introduction: the principal technical scheme of heat storage in an aquifer and three main problems that should be solved to forecast the good functioning of this technology: to control the dynamics of the interface between the hot and the cold water; to know calculate the heat leaks beyond the aquifer; to take into account the phenomenon of water circulation. 

Dynamics of the interface between hot and cold water: equations of heat transport and water flow; separation of flow and heat transport problems; method of streamlines; hydrodynamic problem of a doublet of wells; solution of the hydrodynamic problem by the method of complex potential; calculation of streamlines: detection of the zones of influence of two wells; solution of the heat transport problem along a streamline; explicit relation for the heat front; calculation of the heat front depending on the injection rate; critical injection rate; optimal parameters of the system. 

Calculation of the heat leaks outside the aquifer: we explain the method of Lauwerier, give a short demonstration how this condition has been obtained, and give the examples of its application to geothermal heat storage.

Thermal convection and water circulation in aquifer: explanation of the Rayleigh-Benard convection; effect of thermodiffusion as a second mechanism that can provoke water circulation ; insufficiency of the Darcy equation; Brinkmann’s model of water flow in porous medium; the method and examples of calculating  

2. Underground storage of electricity/hydrogen: technical principle and industrial examples: Hydrogen properties, production, use; Problem of storage and massive storage; storage of pure H2 in salt caverns; Storage of non-pure H2 in aquifers; Storage of H2 in methane storage; the main hydrodynamic problem: lateral spreading and leakage. 

3. Gravitational storage of electricity: technical principle and industrial examples in the world and in France; principle of calculating the balance between the energy stored and energy consumed; optimal parameters of the storage; new versions of gravitational storage.

4. Underground storage of liquefied gas in tight rocks: technical principle and industrial examples: main problems; calculation of the water table in rocks and the temperature field.   

5. Energy storage by compressed air: technical principle and industrial examples: calculation of the degree of air compression and optimal pressure.