IMPSA completes tests for Kalayaan power turbines

IMPSA's research and development hydraulic laboratory in Argentina has completed testing the scale model for the turbines to be installed in the Kalayaan power plant in the Philippines, and the company has begun the fabrication of key components such as the runners.

Following these optimization tests the Kalayaan's turbines will perform a maximum output of 178 MW, a maximum-guarantee-pumping efficiency of 92.66 percent and an average-weighted-generation efficiency of 91.5 percent, all of which are above the level guaranteed to the National Power Corp. (Napocor).

Kalayaan, which comprises of four machines of 172 MW each, is the largest power plant in the Caliraya-Botocan-Kalayaan hydropower facility. Two units will soon be upgraded as part of the rehabilitation program while another two units will be added within 28 months, bringing Kalayaan's total output to 690 MW.

President Estrada saw the model of the Kalayaan turbine during his visit to IMPSA's headquarters last September. There, Bernardo Beling, the head of the laboratory, and hydropower expert Dr. Leopoldo Millan, gave the President a short briefing on the tests being conducted. The parameters of the pump-turbines are simulated in an extensive test where thousands of measurements are made through a data acquisition system with the support of complex-mathematical models and advanced-computer-aided-design tools.

Testing the Kalayaan design involved two steps. First, measurements were taken on a small-scale turbine which, except for its size, is virtually identical to the turbines which will be fabricated by IMPSA. These tests were done in order to assess the units' output, efficiency, cavitation behavior, runaway speed, as well as measure pressure fluctuations and hydraulic forces exerted on other components of the power plant. Next, the data is converted to the level of the actual turbine size to arrive at accurate projection of the plant's performance.

Francisco Ruben Valenti, president of IMPSA Asia, said that the company has optimized the shape of the turbine water passage and the runner for the pump-turbines and that the fabrication of the runner and other critical parts of Kalayaan, Caliraya and Botocan have begun in order to comply with the exigent delivery time of the project by the second half of the year 2002 as outlined by the current Program Development Plan of Napocor.