Output Tests of Shallow Rotorua Wells

Abstract

Production from the Rotorua geothermal field is predominantly from 400 shallow, medium enthalpy, 100 mm diameter wells. Over the last three years considerable expense and effort has been put into the testing of these wells. The output testing was carried out using a total flow calorimeter while continuously recording the well head pressure. Information about the output characteristics of over 30 wells has been collected. as either high pressure (3 bar g -9 bar g) or low pressure (0.5 bar g -3 bar g) depending on the flowing well head pressure. The output characteristics of two typical wells are described. Results are also presented to show the effect of calcite deposition on the mass flowrate from a low pressure well.