Text and Photos by Henrylito D. Tacio
Without water, life itself would cease to exist. As Albert Szent-Gyorygi, Hungarian biochemist and Nobel Prize for medicine, puts it: “Water is life’s matter and matrix, mother and medium. There is no life without water.”
All doctors and health professionals know that. Water, next to air, is the element most necessary for survival. Water makes up more than 60 percent of our body weight. Proteins make up only 18 percent while fats encompass 15 percent, minerals 4 percent, carbohydrates 2 percent and vitamins less than one percent.
But perhaps only very few know that water can also be a source of electricity, another important thing in our modern lives. “We all need electricity,” said Von Hernandez, Executive Director for Greenpeace Southeast Asia. “It is vital – it powers our lives, runs our hospitals and schools – we need it for every aspect of our lives.”
Water is one renewable energy source that has not been fully tapped until now. After all, water covers over 70 per cent of the earth’s surface. Electricity produced by water movement has been used for decades. About 16 percent of the world’s electricity is generated by hydropower.
According to the Washington-based Worldwatch Institute, the world’s top five producers are Canada, China, Brazil, the United States and the Russian Federation.  Several countries, including Brazil and Norway, obtain almost all their electricity from this one source.
Hydropower can be generated by water falls (the first hydroelectric plant was built on Niagara Falls in 1878), rushing rivers and streams, and manmade dams, all of which allow a controlled amount of water to pass through the pipes that spin turbines – creating electricity.
Electric power is measured in units called watts. A watt is equal to one joule per second. The total generating capacity of a power plant is measured in kilowatts for 1,000 watts and megawatts for one million watts.
Enormous dams such as the Hoover (1,455 megawatts) and the Grand Coulee (6,180 megawatts) produce large quantities of power. “Growing interest in developing hydroelectric power is largely an outgrowth of governments’ desire to be more self-sufficient in energy and to provide low-cost electricity,” wrote Cynthia Pollock Shea in Renewable Energy: Today’s Contribution, Tomorrow’s Promises.
A World Bank report in the 1980s showed the Philippines as one of the “thirteen largest additions to hydroelectric capacity in developing countries.” From an operating capacity of 940 megawatts in 1980, it went up to 2,195 megawatts in 1985. In 1998, the total hydropower capacity stood at 2,304 megawatts or almost 20 percent of the country’s total installed capacity.
According to the Department of Energy, there are 1,081 hydropower potential sites scattered throughout the country. In a lecture convened by the Press Foundation of Asia for community journalists in 1994, then undersecretary of the Department of Energy Rufino Bomasang said: “Hydropower can produce a lot of megawatts.”
In Mindanao, 52% (662 megawatts) of its power comes from hydropower.Â
The Sibulan Hydroelectric Power Plants in Sta. Cruz, Davao del Sur, for instance, have been generating 42.5 MW for Davao since 2010. Composed of two cascading plants, the Sibulan Hydro A produces 16.5 MW and the water that it utilizes is reused in the Sibulan Hydro B to produce another 26 MW.
Most of the hydropower plants in the country are in the form of a dam that backs up the water and raises the level. The released water falls into a turbine that generates electricity. “Impounding a river radically changes the surrounding ecosystem,” Shea wrote. “Nutrient-bearing sediments, instead of being deposited on agricultural floodplains and providing food for downstream fish, accumulate behind turbines and dams. Hydroelectric dams may also change the temperature and oxygen content of downstream waters, altering the mix of aquatic and riparian species.”
Smaller hydropower plants, however, do not necessarily require dams. They use a series of pipes with turbines inside which are turned by the current. During his lecture, Bomasang said that “we have the mini-hydro and micro-hydro plants, with a potential of as much as 200 megawatts in the Cordilleras alone.”
He added, “No rice floods are flooded – just a very short dam to collect and divert the water, use it to turn the turbines, and then return the same amount of water to the creek.” Indeed, they have less negative impact on the local ecosystem.
But are hydropower plants really environment-friendly?  Some scientists believe that hydropower from manmade dams produce significant amounts of carbon dioxide and methane, which are greenhouse gases closely connected to climate change.
“Large amounts of carbon bound up in trees and other plants are released when a reservoir is initially flooded and the plants rots,” Worldwatch points out in a recent report. “And as plant matter settling on the reservoir bottom decomposes without oxygen, it leads to a buildup of dissolved methane, which is released into the atmosphere when water passes through the dam’s turbines.”
To operate well for many decades, hydro projects require sound management, not just of equipment, but of entire watersheds. “Hydroelectric power will not be truly renewable until the functions of flood control, irrigation, transportation, power production, tree planting, fisheries management, and sanitation are coordinated within the overall goal of maintaining healthy and productive rivers,” Shea reminded.
In the final analysis, however, “hydroelectric power creates virtually no pollution problems,” writes H. Steven Dashefsky, the man behindEnvironmental Literacy: Everything You Need to Know About Saving Our Planet. “Small-scale projects cause little harm to the environment, but larger projects are environmentally destructive.” (Next: Power from Down Under)
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