An Approach for Characteristics Determination of Initial State in a Geothermal Field

Abstract

México contains more than 4200 thermal manifestations along its territory. To date five geothermal fields are exploited continuously whose electricity generation capacity is in the order of 925 MWe. Four of these geothermal fields are exploited by Comisión Federal de Electricidad (CFE) and the other one is exploited by a private investor. Even though the major electrical generation is being produced by Cerro Prieto geothermal field, along Mexican neovolcanic belt are located the next two second main fields in México (Los Azufres and Los Humeros). In Los Humeros have been found wells with single behaviors with particular characteristics of high temperature (in the rank of 350 °C), including those neighbor, which allows to consider the compartmented behavior hypothesis. Additionally, it has been found, as a general characteristic of field rock formation is its low permeability, influencing in production flow rate and drawdown pressures. The use of the analysis of thermodynamic characteristics behavior, after well completion, allows taking decisions for determining the appropriate time for carrying out production test. It is mainly important, the identification of appropriate thicknesses be exploited in each well, which represents the aim of having successful results through a producer well with electrical generation capacity. In the wells generality, found parameters during drilling, are the technical base for taking decisions on the best completion depth and to select the thickness which must be exploited, in order their productivity assure. Obtained parameters during well completion and before its exploitation start up, are used in this work for static characterization of Los Humeros Geothermal field into the GEMex project