Introduction

With reference to low enthalpy geothermal systems, the developed portable device allows the evaluation of the advective velocity of the thermal plume due to the re-injection of hot/cold water into an aquifer. This parameter is derived by using a proper cross-correlation algorithm.

Technical features

The portable device could allow to determinate by a rigorous cross-correlation, the advective velocity of thermal plume related to hot/cold water re-injection into the aquifer e.g. due to geothermal open loop systems. The advective velocity of thermal plume, is obtained by statistical analysis of temperature monitoring data, registered by normal probes every hour for a minimum period of 3 months in the injection well and in a control point (piezometer or well) downstream of the reinjection. The obtained advective velocity value corresponds to the value until now obtained by the use of analytical formulas, which require the knowledge and then the measure of several other hydrodynamic parameters. The use of the proposed device could allow instead the direct calculation of the advective velocity of thermal plume in a single step. The algorithm, written in imperative programming language, can be compiled on different operating systems such as Android and Windows.

Possible Applications

• Plant design;
• They are also often required by law to obtain the authorization of open-loop geothermal plants construction
• Renewal of license use for open loop systems.

Advantages

• The direct evaluation of the advective velocity without the need to know or measure additional hydrodynamic parameters;
• No need to shutdown the plant;
• The portable device algorithm is compatible with different operating systems.