On the island of Shikoku in the Kôchi Prefecture of Japan, lies a quaint village of Yasunami Water Mill Village. One may wonder whether such a place exists and if there are actually water mills found there. Or is it like a scene dreamt from a movie of Japanese director Akira Kurosawa, where a tale titled ‘Village of Watermills’ portrays a beautiful, warm village whose people live one among nature. If you get a chance to watch this film, you will get an insight into the importance and satisfaction of sustainable living. Mother Nature provides us with everything, we just need to know to utilize them effectively and only to the extent that does not become abusive in nature. More than two-thirds of the Earth’s surface is covered with water. We need to utilize this natural resource effectively in order to sustain ourselves in the long term. Apart from consumption, water can also be used to generate energy and power. Do you remember your science lesson you learned as a child about the water cycle process? When water evaporates from the ocean into air, it forms clouds and the temperature reduces. It returns to the earth in the form of rain and snow that form rivers and streams that eventually flow into the ocean. Hydropower is generated from the power of moving water not still water like lakes. Even this is taken care of by gravitational force, which leads the rivers and streams to flow at incredible speeds sometimes. It is this natural cycle that generates hydropower that we eagerly tap into for our energy consumption. Read further to learn more about how hydropower works.
Working Of Hydropower Plants
In earlier times, water mills were used to generate hydropower. Now they are rarely found and advanced technology such as water turbines has taken its place. No matter how advanced, it still runs on the basic concept of extracting energy produced by flowing water. Advanced technology used in hydropower plants work on the same foundation. The process in which they work is explained below:
- Rivers are blocked in various points on their course with construction of dams which create a large reservoir of water.
- Once the dam gates are opened, the water forcefully gushes out through a pipeline (called penstock) which is connected to the turbine. The water pressure in the pipe begins to rise.
- A generator is attached to the turbine through a shaft.
- At the end of the pipe, the water turns the turbine blades that are connected to the generator.
- In tandem with the each rotation of the turbine blades, there is a series of magnets inside the generator that rotate too. These magnets rotate inside tightly-wounds copper coils, producing alternating current (AC).
- In the powerhouse, the transformer that is connected to the generator converts AC into higher voltage electricity.
- The power lines then carry this electricity from the powerhouse to the end consumer.
- The water used in this process is carried through pipelines called ‘tailraces,’ back into the river downstream.
Hydropower is a renewable, natural resource that can be effectively used to meet energy needs. Hydropower is a more preferred source of energy as it is considered less expensive compared to sun and wind power generation.