| Abstract |
CalEnergy International Ltd. is currently operating three geothermal plants in the province of Leyte. These are the 118-MW CE-Cebu Geothermal Power Co. located at Upper Mahiao, the 232-MW Visayas Geothermal Power Co. located at Malitbog, and the 180-MW CE-Luzon Geothermal Power Co. located at Mahanagdong. The Visayas Geothermal Power Co. and CE-Luzon Geothermal Power Co. are using the double flow and dual entry condensing type of turbines. However, they differ in the type of condenser. The former uses a direct contact type condenser while the latter uses a surface type condenser. Both plants are using cooling towers to cool down the high-temperature condensate from the main condenser using the cooled recirculating water from the cooling tower. The design operating conditions of these condensers have to be maintained in order to produce the design power output. Hence, it is necessary to determine and evaluate the actual performance level of these cooling towers. The actual performance level of an operating cooling tower can be accurately determined only by thermally testing the tower. Once the average test values have been established, comparison with the design capability is relatively easy. The measure of thermal capability of the cooling tower is the ratio of the test water circulating rate to the circulating water rate predicted by the manufacturerÆs performance curve. In addition, CTI Code provides an alternate method for evaluating capability, whereby the "characteristic curve" is used in conjunction with the basic theoretical data. This paper focuses only in the measurement of cooling tower thermal capability using manufacturerÆs performance curve. Results of thermal performance testing showed that the cooling tower of the Mahanagdong Power Plant (CE-Luzon Geothermal Power Co.) is more efficient with its % capability of 106.6%. In comparison, the cooling tower of the Malitbog Power Plant (Visayas Geothermal Power Co.) gave a lower % capability of 92%. |