How do hydrothermal doublet systems work?

Today (2019), 37 hydrothermal doublet systems commercially produce thermal energy in the Paris basin. The produced thermal energy is used for direct house heating and hot water supply. The geothermal energy is transferred to secondary loops using heat exchangers and reaches the end-user through separate distribution networks.

Do hydrothermal systems have high enthalpy?

Provided by the Springer Nature SharedIt content-sharing initiative Policies and ethics Hydrothermal systems use the thermal energy of an aqueous fluid at greater depths. Depending on the heat content of the fluid, systems with high enthalpy can be distinguished from low enthalpy systems.

How do hydrothermal systems work?

Hydrothermal systems use natural deep groundwater residing in geological reservoirs with high hydraulic conductivity. The reservoirs are embedded in other geological units with different properties.

How are hydrothermal systems used for geothermal purposes?

Exploitation of hydrothermal systems for geothermal purposes is typically via geothermal doublet systems, which consist of two boreholes drilled to target depths, one for abstracting the hot water and the other for returning the cooled water back into the aquifer (Figure 6).

What are the parameters of a hydrothermal system?

The envisioned products of the hydrothermal system have a controlling effect on the parameter values. If the system should produce electrical power then T min is about 120 °C and production rate Q should be higher than 50 kg s −1 (limits in the year 2020).

What are the components of a shallow geothermal installation using groundwater?

The basic components of a shallow geothermal installation using groundwater are: geothermal wells for groundwater production (Fig. 6.2) and injection, and a groundwater drive pump and water-to-water plate heat exchanger adapted to the characteristics of the groundwater hydrochemistry.